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target1
11-28-2011, 1:00 PM
I'm planning on buying my first carbine and is wondering if I should get a Gas Piston rifle vs. DI system. Funds are limited, so I looked at the Stag Model 8 which is the cheapest gas piston rifle. Any thoughts?

-hanko
11-28-2011, 1:05 PM
I'm planning on buying my first carbine and is wondering if I should get a Gas Piston rifle vs. DI system. Funds are limited, so I looked at the Stag Model 8 which is the cheapest gas piston rifle. Any thoughts?
If funds were limited, I'd pick direct impingement...

If you're looking at a piston weapon, what's your perceived advantage over a DI weapon?...if it's less cleaning, cleaning an AR is a fast process.

Also, if you're looking at a piston gun, why the question in the first place?:confused:

I'd still pick the DI gun as parts are a LOT more readily available for the gas system v. pieces on a proprietary piston gun.

-hanko

HK Dave
11-28-2011, 1:05 PM
You are better off saving the money you "would" have spent on the piston and buy yourself a better DI rifle. :)

Do a quick search online for PISTON vs DI and you will find at least half a year worth of reading.

Good luck!

Oh yes... and just to spite the piston folks and get this started off right... PISTONS ARE A GIMMICK. :D

jonjonkills101
11-28-2011, 1:19 PM
im building a piston AR right now...to be honest in my research it doesn't matter what you pick, it just depends on what you want. everyone is going to have their side in this whole piston vs. DI world, and there are certain trade-offs that some people will despise, and some will love.

if you just want a basic AR you can fix up and modify and shoot the hell out of, you might as well go with DI. as for me, im always up for challenges and trying different things, so i went the piston direction.

Ubermcoupe
11-28-2011, 1:19 PM
If funds were limited, I'd pick direct impingement...

This.

In a piston system, the gas impinges on the piston versus the bolt, functionally its very similar (some call it the same) to DI except instead of cleaning the bolt, you’ll have to clean piston and the gas system.

Unless you have a ton of money, or have some specific reason you need (not want) a piston system, get a DI set up and call it a day.

I’m not a sure a cost effective/reliable/easy to clean piston system exists for the casual shooter... Maybe someone on here can correct me on that.
Just my opinion

:oji:

Colt-45
11-28-2011, 1:24 PM
If funds are limited do yourself a favor and get a DI.

I have DI and piston, there's advantages and disadvantages for both.

My suggestion is shoot and learn the AR platform in DI then get a piston.

If you want piston stick to the high end rifles like HK, LWRC etc.

-hanko
11-28-2011, 1:26 PM
Iím not a sure a cost effective/reliable/easy to clean piston system exists for the casual shooter... Maybe someone on here can correct me on that.
Just my opinion

:oji:
It does exist, but it's used on FAL's.;)

Piston AR's came about just like new caliber cartridges do...when you market the standard pieces in operator/tier i/video-game-tactical-wannabee versions until there's nothing left, you add piston systems to keep the cash flow running...

The question of why add complexity to an existing system does rear its head.

-hanko

The Virus
11-28-2011, 1:32 PM
Piston. the AR platform should have been built that way from the start.
Piston actually simplifies the weapon via the very nature if the piston design.

the resulting weapon has LESS parts than its DI counter part, once again adding to its simplicity.

Ask yourself what is the most simple most prolific rifle out there, the AK's
you don't see a gas tube in that design, what you see is a piston.

stix213
11-28-2011, 1:35 PM
If you don't know if you should go Piston or DI, that means you should go DI.

21SF
11-28-2011, 1:43 PM
They both have gas tubes and pistons....;)

acaligunner
11-28-2011, 2:03 PM
The Virus;Piston. the AR platform should have been built that way from the start.
Piston actually simplifies the weapon via the very nature if the piston design.

The AR was never designed to run with a piston system. Also there are many piston guns that jam also. The famed FN/FAL jammed in the deserts of the middle east. The AK can also jam, my brother is alive due to a Russian AK that jammed.

the resulting weapon has LESS parts than its DI counter part, once again adding to its simplicity.

I heard that the piston design has more parts than a DI, I'll look into that later, but there are a heck of a lot of DI AR/M16's that are working in combat right now. I have only heard about the DI having problems in the battle of Wanot Afghanistan.

Where soldiers fired their M16's so fast on full auto that the weapons jammed, but this was only after 12+ magazines had been fired.

To this I have to say that the basic AR/m16's are not light machine guns, and are not made to fire that many rounds.

Ask yourself what is the most simple most prolific rifle out there, the AK's
you don't see a gas tube in that design, what you see is a piston.

AK's are a totally different weapon, also the DI AR offers many advantages over the AK. To it's credit, it's been fighting right along with the AK, all over the world.

So unless your going to soak your rifle in water, shoot 1,200 rounds on full auto, as fast as you can, going to run suppressed, or not going to run your weapon wet, and don't want to keep your SD weapon clean, then yeah, I see some advantages to the piston design.

acaligunner

Droppin Deuces
11-28-2011, 2:07 PM
Th

Iím not a sure a cost effective/reliable/easy to clean piston system exists for the casual shooter... Maybe someone on here can correct me on that.
Just my opinion

:oji:

Sure it does. It's made by Adams Arms. The entire system pops out of the front of the gun in about two seconds. I know everyone likes to disregard them, though, because they don't gouge people as much as the so-called "high end" companies do. I have a lot of experience with their product and can only point out one bad thing about it, which is the overall weight. They do make an ultra lightweight version, though.

The Virus
11-28-2011, 2:12 PM
Adams Arms is a great system. I prefer it over my LMT...

DI offers NO advantages over piston, while piston has many advantages.

There absolutely a benefit to running piston.

FiveSeven
11-28-2011, 2:14 PM
Piston.
.... Like someone famous stated, "crapping where you eat ain't cool".

HK Dave
11-28-2011, 2:19 PM
Piston. the AR platform should have been built around a piston from the start.
Piston actually simplifies the weapon via the very nature of the piston design.

Currently piston AR15s have MORE parts than its DI counter part, once again adding to its complication.

Ask yourself what is the most simple most prolific rifle out there, the AK's
you don't see a gas tube in that design, what you see is a piston.

There fixed it for ya. ;)

The AR15 design was never meant for a piston.

Adding a piston to an AR15 means you need proprietary BCGs, sometimes channels to deal with carrier tilt, proprietary piston system, and sometimes proprietary barrels. Means if your system is down, it'll probably be down for a while since you have to procure parts that could take time to get ahold of.

It's not worth doing unless you've got oodles of money to throw around.

The Virus
11-28-2011, 2:26 PM
[QUOTE=acaligunner;7575748]The AR was never designed to run with a piston system. Also there are many piston guns that jam also. The famed FN/FAL jammed in the deserts of the middle east. The AK can also jam, my brother is alive due to a Russian AK that jammed.

That is similar to saying a pushrod engine wasn't designed to run with overhead cams. You are correct, however some Italian guy realized a more efficient design and viola the overhead cam engine was born.

"Jams" are not typically caused by the operation system unless of course its a DI gun that hasn't been maintained.

A "jam" usually refers to a double feed, a fail to feed, a fail to extract or perhaps a bolt over.
Most "jams" are the fault of bad mags, if were talking about a weapon that suddenly starts "jamming"

On a brand new untested gun it could be caused by many issues.

My point is that if it's a functioning Piston AR vs a functioning DI AR.
The Piston wins every time in every way.

The added weight of a piston system is about one half of a pound.

GM4spd
11-28-2011, 2:31 PM
http://www.fototime.com/F3B80EB5172F75A/standard.jpg

HK Dave
11-28-2011, 2:32 PM
I bet there is no Piston AR that is as accurate as the best match DI AR.

HK Dave
11-28-2011, 2:33 PM
http://www.fototime.com/F3B80EB5172F75A/standard.jpg

ROFL

steve92407
11-28-2011, 2:33 PM
how can someone say piston has less parts than di. replace one hollow gas tube with a push rod,spring,bushing.replace gas block with adjustable block and add bolt spring.now fire the damn thing and lose 1 moa and $350!

target1
11-28-2011, 2:33 PM
Sorry, I left out the model 2 I wanted to get. The reason I ask is because I can get a deal on a stag model 8 vs the model 2.

HK Dave
11-28-2011, 2:36 PM
target1, just get yourself a DI AR, spend the extra money on ammunition and go have a ball. When you've burned through a Piston ARs price worth of ammo, start looking for what else there is. :)

HK Dave
11-28-2011, 2:37 PM
how can someone say piston has less parts than di. replace one hollow gas tube with a push rod,spring,bushing.replace gas block with adjustable block and add bolt spring.now fire the damn thing and lose 1 moa and $350!

+1000

Cracks me up how people think their Piston AR is suddenly an AK47. ;)

Colt-45
11-28-2011, 2:40 PM
There fixed it for ya. ;)

The AR15 design was never meant for a piston.


Face it, technology advances. Improvements happen.

The Virus
11-28-2011, 2:41 PM
There fixed it for ya. ;)

The AR15 design was never meant for a piston.

Adding a piston to an AR15 means you need proprietary BCGs, sometimes channels to deal with carrier tilt, proprietary piston system, and sometimes proprietary barrels. Means if your system is down, it'll probably be down for a while since you have to procure parts that could take time to get ahold of.

It's not worth doing unless you've got oodles of money to throw around.

Actually a DI BCG has 3 gas rings
A bolt carrier key
and 2 key screws.
thats 6 pieces a piston BCG does not have.

Piston additional parts Gas Plug
Piston rod
spring
bushing

so if the gas tube and piston rod cancel each other out
the piston gun has 3 LESS parts. If the BCG has a bolt spring than the Piston gun has 2 Less parts.

Fixed it for ya ;-)

C4iGrant
11-28-2011, 2:44 PM
I'm planning on buying my first carbine and is wondering if I should get a Gas Piston rifle vs. DI system. Funds are limited, so I looked at the Stag Model 8 which is the cheapest gas piston rifle. Any thoughts?

First, I understand that you do not know anything about AR's, but what do you "Perceive" to be the problem with DI AR's?



C4

Full Clip
11-28-2011, 2:45 PM
If money is tight, there are a lot of lightly used, high-quality DI parts on the market.... not so much with the piston systems...

Colt-45
11-28-2011, 2:47 PM
DI lovers/purists fail to recognize that technology advances and improves. They also like to judge piston AR's by low quality manufacturers or conversions kits. I'd like to know how many Hk416 or LWRC owners have problems with carrier tilt or other so called piston problems.

The way i see it, DI M4's should be used in urban environments, perfect for law enforcement. Rarely does law enforcement have to deal with putting their weapons through harsh environments and when they do, they're probably not in the field for very long. Especially not long enough that they have to clean their weapons while in action.

Soldiers and Marines should be given piston AR's.

The problem is very evident, you must be blind not to see it. Shoot a piston ar(from a reputable manufacturer) and a DI ar for a small amount, 100 rounds each. Take out the bolt carriers in both, grab a rag and tell me what you see.:confused: You don't have to be a special forces tactical operator to realize this, the DI bolt carrier will be much more dirty. Bottomline, the DI AR ****s where it eats. This is not a problem if you have the ability to clean it every so often, no it doesn't need to be cleaned every 100-200 rounds but hopefully you get the idea.

I like and own both DI and piston AR's but I will not negate the truth, piston AR's from reputable manufacturers are definitely more reliable than DI's. Also, from personal experience, the smaller the barrel on DI's the quicker the rifle builds up carbon and dries up lubricants. However, DI AR's are not obsolete and are perfect for urban applications.

C4iGrant
11-28-2011, 2:49 PM
Adams Arms is a great system. I prefer it over my LMT...

DI offers NO advantages over piston, while piston has many advantages.

There absolutely a benefit to running piston.

This is false.

Here are the issues with ANY piston system:

1. Cost
2. Weight
3. Felt Recoil
4. Accuracy loss
5. Parts availability

Go to some carbine schools with your piston guns, have something break or fail and see if anyone in the class has that part. ;)


If you want a piston gun, buy from that was designed FROM THE GROUND UP around the piston. This would firearms like the SCAR, AK, etc.




C4

acaligunner
11-28-2011, 2:59 PM
Are you gonna run the rifle this hard. Let the ad run, then the vid will start.

http://video.nytimes.com/video/2010/01/12/world/asia/1247466496261/m-4a1-firing-test.html

acg

SOCAL-PRINCE
11-28-2011, 3:01 PM
OP, I have used the DI system in the Army for 8 years and in my opinion it's a good system. It is sensitive to dirt and fouling so more sensitivity has to be placed on maintenance. It's an effective and proven system that simply works.

With that said, I now own a LWRC M6 and a stag Model 8. DI is good but IMHO piston is better in many ways. Reliability, ease of maintenance, and extended maintenance schedule just to name a few. I certainly have more confidence in a piston system and it would have made life in the Army much easier.

The propriety parts and higher price does suck but it wasn't a deal breaker for me. And with the added benefits its worth it. Most of the current pistons systems have BCG's designed to prevent carrier tilt so I wouldn't sweat it. There is added weight but if you can't carry an extra pound or less you need to hit the gym. LOL!

Like others have said if your not going to submerge your gun in water or bury it the mud then get a DI. But it's good to know that with a piston system you can do that all day.

The Virus
11-28-2011, 3:04 PM
Iv'e put my piston guns through at least 80 hrs of heavy use during training.
Every malfunction i have witnessed are from DI guns.
Cost doesnt effect weapon performance.

A half pound of weight doesn't concern me. I only run a light on my rifle.

I have no issues with recoil, a good muzzle brake will take care of that. (its a .223 for crying out loud)

All I can say about accuracy is i have no problem hitting 10" steel at 400 yds with a red dot.

anyone should have spare parts for any type of weapon they are running.

I have a spring, a rod&bushing and a gas plug in my kit. ;-)

n0xname
11-28-2011, 3:14 PM
Runnin the stag model 8. About 2k rounds through it. Ran brass and steel no fte no ftf no fte. The weight is not much diffrence and very clean overal weapon. Accurate and durable

HK Dave
11-28-2011, 3:20 PM
And you guys think the OP needs to spend extra money on the piston because? :)

:popcorn:

HK35
11-28-2011, 3:31 PM
I'm planning on buying my first carbine and is wondering if I should get a Gas Piston rifle vs. DI system. Funds are limited, so I looked at the Stag Model 8 which is the cheapest gas piston rifle. Any thoughts?

I own and shoot both DI & GP ARs. I personally prefer to shoot GP due to ease of cleaning because I hate taking the BCG apart. I much rather run a bore snake through the barrel and call it a day.

Other than that DI works just as well for general plinking. No real need for a GP on a semi-auto AR unless you often take round intensive (800-1000+ rounds/day) carbine classes.

You'll have to run a DI very hard to generate enough heat in the BCG & chamber to cause issues. Not a problem if you are just taking your time plinking.

@ the OP, do you plan on doing mag dump after mag dump with your AR for a few hundred rounds at a time? If so a piston would be better but if not, just go with a decent quality DI like a Noveske or Larue :43:

acaligunner
11-28-2011, 3:32 PM
And you guys think the OP needs to spend extra money on the piston because? :)

:popcorn:

By now the OP is so confused he probably just went with a Shotgun. :confused:

Can we now talk about who we would like to wake up to < Blonds or Brunettes>!!!

acaligunner

SOCAL-PRINCE
11-28-2011, 3:32 PM
He doesn't have to, but if he has the means to then the benefits are certainly worth it. It's good that your DI system works for you. That's why it's all about at the end of the day. From my experience I've found the piston system to be much better, worth the extra cost, and it works better for me. That's all I'm saying....

FeuerFrei
11-28-2011, 3:34 PM
I'm planning on buying my first carbine and is wondering if I should get a Gas Piston rifle vs. DI system. Funds are limited, so I looked at the Stag Model 8 which is the cheapest gas piston rifle. Any thoughts?

Wabbit season! ...Duck season! ...!!
Wabbit season! ...Duck season! ...!!Wabbit season! ...Duck season! ...!!

... DI vrs GP on an AR debate will probably still be argued after we are all dead.
I know you didn't mean to start anything negative but, many gun businesses depend on the DI being around in it's current form. If you sell a lot of DI system parts and accessories then the DI makes good business sense. But I digress.
Buy the AR type you can afford and go shoot it. Learn to take it apart and know how it operates. Upgrades will soon follow.
There are many good GP AR types out there that can be had for decent price.
Well known companies will back up their products.
An AR in either form is an easy beast to care for and even easier to learn to shoot well.
Good luck on your new rifle. DI or GP.

HK Dave
11-28-2011, 3:38 PM
By now the OP is so confused he probably just went with a Shotgun. :confused:

Can we now talk about who we would like to wake up to < Blonds or Brunettes>!!!

acaligunner

Redhead ;)

Or like how I collect guns... all of them please. Thank you very much.

Agent Tikki
11-28-2011, 3:46 PM
I went through the same thing as you.

My first AR upper was a Stag Model 8. I sold it. I don't miss it. Welll......(See below)

I've bought only DI uppers after that. Here's why I chose the DI over the pistons:

1) Recoil is much smoother. The sharp crack of Model 8s cylcing made me wince.
2) Never had reliability issues with my DIs.
3) DIs are inherently more accurate.
4) DIs are cheaper.
5) Psitons are only marginally heavier! Acceptable trade off! But no, all that weight is forward of the center of balance. Makes your AR even more front heavy.

The ONLY thing I miss of my old Stag Model 8, is cleaning it. Its was soooooo fast and easy. And hey I'll admit it, sometimes I just don't feel like cleaning.

I know, I know. I thought new modern design! Must be better! Its gotta be more reliable than a 30+ year old design! The old fogeys can have their DIs I want the reliability of a piston! Unless I was planning on an extended tour in the sandbox, or storming the beaches of Normandie, DIs for me all the way now.

Droppin Deuces
11-28-2011, 3:54 PM
Something tells me that when Colt starts selling their piston gun, people's opinions will suddenly change.

"OMG! Colt piston!" *drool* *fap, fap, fap, fap, fap*

HK Dave
11-28-2011, 4:11 PM
Hehe, the piston is an older system than the DI. In actuality, the DI is the newer more technologically advanced system. The Piston is just new in the AR15.

The ONLY thing I think the Piston has as an advantage over the DI is the FACT that it's easier to clean... whether one really needs to clean is an item for debate.

Anyhow, here are a few links that should be read. ;)

The Big M4 Myth Fouling by the DI System Makes the M4 Carbine Unrealiable (http://www.defensereview.com/the-big-m4-myth-fouling-caused-by-the-direct-impingement-gas-system-makes-the-m4-unreliable/)

DI AR-15 Runs 15,000 rounds of Wolf WITHOUT Cleaning Before Failing (http://www.thefirearmblog.com/blog/2010/06/09/a-clean-wouldnt-hurt/)

Striker
11-28-2011, 4:30 PM
DI lovers/purists fail to recognize that technology advances and improves. They also like to judge piston AR's by low quality manufacturers or conversions kits. I'd like to know how many Hk416 or LWRC owners have problems with carrier tilt or other so called piston problems.

The way i see it, DI M4's should be used in urban environments, perfect for law enforcement. Rarely does law enforcement have to deal with putting their weapons through harsh environments and when they do, they're probably not in the field for very long. Especially not long enough that they have to clean their weapons while in action.

Soldiers and Marines should be given piston AR's.

The problem is very evident, you must be blind not to see it. Shoot a piston ar(from a reputable manufacturer) and a DI ar for a small amount, 100 rounds each. Take out the bolt carriers in both, grab a rag and tell me what you see.:confused: You don't have to be a special forces tactical operator to realize this, the DI bolt carrier will be much more dirty. Bottomline, the DI AR ****s where it eats. This is not a problem if you have the ability to clean it every so often, no it doesn't need to be cleaned every 100-200 rounds but hopefully you get the idea.

I like and own both DI and piston AR's but I will not negate the truth, piston AR's from reputable manufacturers are definitely more reliable than DI's. Also, from personal experience, the smaller the barrel on DI's the quicker the rifle builds up carbon and dries up lubricants. However, DI AR's are not obsolete and are perfect for urban applications.

I think both have their place, but the only piston AR that has succeeded in the s-holes around the world is the HK 416. If we're talking that gun, ok. If you're talking about a different Piston driven AR, what do you want to issue? To my knowledge, none other than the HK have held up under the rigors of harsh environments. Add this to the fact that you put, just for instance, an LWRC piston over there and it breaks, where do the parts come from? I am interested to see Colt's version. It's taken them awhile to get to it, so I hope it's stellar. A Piston gun is great if you're running an SBR and or you're using a suppressor quite a bit and or you're firing full auto quite a bit. I see the advantages if you're doing this type of work.

For the OP, if he wants a proven system, that's only the HK and how much for a 416, if you can even get them? What's the cost on those? Hey I want a 416 as well, but it just doesn't work out as a good financial move unless you just want one, which is fine. A good DI gun, say Daniel Defense, BCM, Colt, Noveske, LMT etc will cost a lot less meaning you'll still have money for mags, ammo, a sling, a light and maybe even a fun go shoot with ex-Delta guys class. It just makes more financial sense for most. If you want a piston AR, pick a good one. If you want a piston AR that's been proven in S-holes around the world, pick the HK. Nothing wrong with just wanting one.

Btw, a DI AR doesn't need to be kept spotless to run, it does, however, need to be run wet.

Don29palms
11-28-2011, 5:32 PM
Ok I'll throw in my 2 cents. I have 2 ARs that I built. 1 is a DI and the other is a GPU that uses an Adams Arms kit. As you can tell the DI vs GPU arguements rage on. It like Ford vs Chevy. They both have pros and cons. The one thing that always gets me is the WHAT IF IT BREAKS stuff. Well maintained rfiles don't break very often. I shoot all my guns alot and haven't had any problems with any of them. I don't participate in carbine courses or run & gun stuff. If you want a less expensive rifle DI will be less expensive than GPU. There is nothing wrong with a DI rifle and they are fine obviously. With that being said, in my opinion, If I could only have 1 AR it would be a GPU.

I know that's no help. Good luck with your purchase.

P.S. Look at it this way, It doesn't matter what you buy because it won't be your only one.

goodlookin1
11-28-2011, 8:25 PM
Gotta chime in. You have different trains of thought: The old school hunter-like minds say, "The AR-15 was not designed to be retrofitted with a piston". The new school, open minded people say, "Screw that, this is the best upgrade i've made for my AR-15". I'm of the latter group. I dont care if it wasnt designed for it. It's not adding any more stress on the gun as any other "piston designed" rifle does, when done properly.

Then there's the myth that it adds so many new parts and that DI is so much simpler. FALSE! My piston system two ADDITIONAL parts and two small springs, replaces three parts, and takes away a part (bolt gas rings: something i've seen fail). That's a grand total of 1 additional main part vs DI! (Not including the small springs). I dont get what all the fuss is about. And the only "load bearing" part is the Op Rod. I think it's a much SIMPLER design, personally.

About the only real con is some additional weight, depending on who's system you have. This point, I will concede.

As for proprietary designs, yes..I suppose there is *some* risk in that, and moreso in this current economic climate. But the worst that is going to happen is that you just replace it with a DI setup if they ever go bust. It's not like you can never get your AR-15 functioning again...

As for accuracy, you're not gonna notice any difference from your standard M4 or the like. Sure, maybe in a match grade setup for long range, but certainly not with your M4 profiled barrel.

As for cleaning, everyone understands that piston systems are internally cleaner and cooler. Anybody who knows anything should understand that metal on metal is subject to wear and break-down. The issue that separates Piston from DI is the additional carbon grime that is introduced. This only adds to wear and tear, along with an increased chance of malfunctions unless you profusely lubricate your system consistently. Who wants to worry about that in a firefight, a day of fun at the range, or any situation?

As for reliability, this is hotly debated. From my personal experience, my piston AR knocks the socks off of the DI counterpart. I would trust my AR in any battle compared to a DI. I dont have to worry about lubing it up, cleaning it out periodically, or anything of the sort. My piston AR runs dry or wet, and i've used many different types of ammo: Hot loads, light loads, crappy loads, steel cased loads, match loads, reloads, etc, all without one single failure to feed, failure to fire or failure to extract, and all without making a single adjustment to the gun/gas/spring/buffer/carrier. Granted, some of this is due to using PMags, some is due to good ammo, but certainly much is due to the rifle.

Maybe i'm not the norm, I dont know. Maybe i got lucky.

Or maybe not...

YMMV

bighead
11-28-2011, 9:38 PM
This is why i purchased my Sig 516 piston rifle.

http://www.youtube.com/watch?v=jLKV1-43R8w&feature=youtube_gdata_player

C4iGrant
11-29-2011, 6:55 AM
Something tells me that when Colt starts selling their piston gun, people's opinions will suddenly change.

"OMG! Colt piston!" *drool* *fap, fap, fap, fap, fap*

I have fired and taken apart the Colt piston gun (6940P). Well thought out design (there own) and will most likely be considered the best if not the best one on the market.

With that said, I will NOT be trading in ANY of my DI guns for one. ;)



C4

starsnuffer
11-29-2011, 3:23 PM
"DI" is a gimmick. All ARs are piston guns. The only difference is that traditional ARs use the BCG as the piston and have a much longer gas tube than "piston" guns.

Spend your money on the best weapon in your budget. Don't get hung up on any one feature.

-W

acaligunner
11-29-2011, 3:43 PM
I would like to see a piston torture test (Maybe a LWRC rifle), like Pat Rogers did with the BCM (Filthy) 14.

According to the results they documented the rifle and what needed repairs, during it's 30,000 + round count.

acaligunner

SureShot241
11-29-2011, 4:04 PM
Are you serious... This AGAIN?!

If it will be a range rifle and you have a low budget, get a DI. It is how the gun was designed.

If it works for the military, its quite good enough for us.

If you plan on going through hell and back, then sure get the piston gun, but know this: most piston guns require better ammo then DI guns, which means you will pay more for ammo in the long run.

Also, to the cleaning debate: If you are so lazy you cannot spend the 10-20 minutes it takes to clean your rifle then get an AK. I personally enjoy cleaning my gun after firing it, it's almost peaceful.

Yes pistons are cool and have some advantages, but unless you have the money to get a good one, get a DI.

What is known about the Di system: It is how the rifle was designed. It works. It is battle proven. It is VERY accurate. It has stood the test of time.


And no I am not bad mouthing piston AR's. I plan on getting one in the future (an Addax ZK)

Droppin Deuces
11-29-2011, 4:08 PM
Are you serious... This AGAIN?!

If it will be a range rifle and you have a low budget, get a DI. It is how the gun was designed.

If it works for the military, its quite good enough for us.

If you plan on going through hell and back, then sure get the piston gun, but know this: most piston guns require better ammo then DI guns, which means you will pay more for ammo in the long run.

Also, to the cleaning debate: If you are so lazy you cannot spend the 10-20 minutes it takes to clean your rifle then get an AK. I personally enjoy cleaning my gun after firing it, it's almost peaceful.

Yes pistons are cool and have some advantages, but unless you have the money to get a good one, get a DI.

What is known about the Di system: It is how the rifle was designed. It works. It is battle proven. It is VERY accurate. It has stood the test of time.

What's a good one? One that works all the time or one with that costs a lot?

SureShot241
11-29-2011, 4:14 PM
What's a good one? One that works all the time or one with that costs a lot?

One that works well, is light, and can take any ammo you throw at it. Cost is not a factor when I look at things, it is only a number... to an extent

Arnelcheeze
11-29-2011, 4:41 PM
If funds were limited, I'd pick a piston AR... they have gone down in price.

If you're looking at a DI weapon, what's your perceived advantage over a Piston weapon?...if it's less cleaning, then all you need is a boresnake and thats it!

Also, if you're looking at a DI gun, why the question in the first place?

I'd still pick the Piston gun as parts are readily available from the manufacturer of the system just order them direct since you should be planning ahead anyways.

I could copy all these replys and replace the words all day long, people with Pistons will love their pistons and DI's will love their DI's pick one and end this debate!

Arnelcheeze
11-29-2011, 4:45 PM
Are you serious... This AGAIN?!

If it will be a range rifle and you have a low budget, get a DI. It is how the gun was designed.

If it works for the military, its quite good enough for us.

If you plan on going through hell and back, then sure get the piston gun, but know this: most piston guns require better ammo then DI guns, which means you will pay more for ammo in the long run.

Also, to the cleaning debate: If you are so lazy you cannot spend the 10-20 minutes it takes to clean your rifle then get an AK. I personally enjoy cleaning my gun after firing it, it's almost peaceful.

Yes pistons are cool and have some advantages, but unless you have the money to get a good one, get a DI.

What is known about the Di system: It is how the rifle was designed. It works. It is battle proven. It is VERY accurate. It has stood the test of time.


And no I am not bad mouthing piston AR's. I plan on getting one in the future (an Addax ZK)
If your piston gun doesn't shoot crap ammo then there is something wrong.

EvoXRiley
11-29-2011, 4:48 PM
ive owned both, a smith and wesson mp15 and a Sig 556 (which i currently still own)
but guns are great, just comes down to your budget

all the DI guys will say DI and all the GP will say GP.

pick what YOU like and what you can afford. simple as that, although to the gentleman saying GP require more expensive ammo, thats some FUD i shoot EVERYTHING out of my sig and it eats it all day long.

good luck to OP

shooterfpga
11-29-2011, 4:48 PM
i have to agree with somethingnis.wrong. with a piston you should have an adjustable gas block which you can set on the fly.

Exdc
11-29-2011, 5:02 PM
From what I've read, there are advantages and disadvantages to both.

Primary piston advantages:
-(very arguably) reliability of the weapon, particularly involving feeding and ejecting
-less carbon wear on the bolt (which is irrelevant if your piston system sheers off the screws holding it to the BCG)
-"easier to clean". well, you're going to be cleaning something.

Primary DI advantages:
-Cost $250-$350 less expensive
-Simplicity (less to go wrong)
-Availability of replacement parts (in case something does go wrong)

Look at it this way: If you have a budget, you might as well stick with DI. There is a reason it's still being used in the military. If your bolt goes bad because you're too lazy to clean it, that's $100-$200, and it will take a while to happen. And a BCG is pretty readily available.

On the other hand, if a piston system goes bad, you have to wait a while. If it's got a warranty, you'll be down a few weeks. If it doesn't, then you're paying to replace whatever is damaged. And the parts aren't cheap, if the original 250-350 price tag has anything to say.

Many people say that the piston systems have less FTF and FTE, but if that comes at the cost of your bolt... (most piston systems place the strain from the piston onto a couple of screws on your bolt; sheer those bolts off, and you've usually got to buy a new one).

Cleaning is irrelevant, because you have to clean either one. If anything, the piston requires you to clean more parts, because you still have some carbon buildup on the bolt, in addition to the piston system.

If you want to go piston anyway, the Adcore B.E.A.R. seems to have fixed most of the original problems with the piston (sheering of bolts, recoil) and may be something to look into.. but it's about $900 for the upper by itself.

I have to agree with the more experienced people on here, DI is the best way to go for now. maybe in the future, the piston system will be 'perfected'. Good luck (:

Jwind
11-29-2011, 5:34 PM
Nutnfancy had a good video about this very debate.

6auXTiqNtEo

C4iGrant
11-29-2011, 7:12 PM
"DI" is a gimmick. All ARs are piston guns. The only difference is that traditional ARs use the BCG as the piston and have a much longer gas tube than "piston" guns.

Spend your money on the best weapon in your budget. Don't get hung up on any one feature.

-W


True! Well almost. The the bolt acts as the piston.


C4

C4iGrant
11-30-2011, 6:56 AM
For those interested, Mike Pannone of CTT did a great write up on the M4 and it reliability.

The Big M4 Myth: “Fouling caused by the direct impingement gas system makes the M4/M4A1 Carbine unreliable.”
http://www.defensereview.com/the-big-m4-myth-fouling-caused-by-the-direct-impingement-gas-system-makes-the-m4-unreliable/



C4

ZombieTactics
11-30-2011, 8:19 AM
Pannone's article really is a classic. It's also evidence of how small details can make huge differences.

(Your link is broken, but this works: CLICK HERE (http://www.defensereview.com/the-big-m4-myth-fouling-caused-by-the-direct-impingement-gas-system-makes-the-m4-unreliable/))

goodlookin1
11-30-2011, 9:00 AM
I dont get the whole, "If it's good enough for the military" argument....does no one understand that the contracts go to the lowest bidder (or really, to who has the best "friends in high places"). Military is not strictly objective with weapon choice: They dont choose the best. They choose the most economical and practical tool to get the job done. If they chose "the best", we wouldnt have our boys utilizing 60 year old technology, plain and simple.

So if you want to support this argument, at least come at it from a "get the job done" mentality. If that was the case, I would agree with those who say this. But the standard AR is certainly not the best option these days.

C4iGrant
11-30-2011, 9:02 AM
Pannone's article really is a classic. It's also evidence of how small details can make huge differences.

(Your link is broken, but this works: CLICK HERE (http://www.defensereview.com/the-big-m4-myth-fouling-caused-by-the-direct-impingement-gas-system-makes-the-m4-unreliable/))

The devil is in the details.

Many people coming out of the Military have a negative opinion of the M16/M4 family. What they fail to realize is the PM's were rarely done on these guns AND they were basically shot out and needed replaced.


C4

C4iGrant
11-30-2011, 9:05 AM
I dont get the whole, "If it's good enough for the military" argument....does no one understand that the contracts go to the lowest bidder (or really, to who has the best "friends in high places"). Military is not strictly objective with weapon choice: They dont choose the best. They choose the most economical and practical tool to get the job done. If they chose "the best", we wouldnt have our boys utilizing 60 year old technology, plain and simple.

So if you want to support this argument, at least come at it from a "get the job done" mentality. If that was the case, I would agree with those who say this. But the standard AR is certainly not the best option these days.

As someone that used to do .Gov contracts (as an agent for the Govt), I can tell you that the lowest bidder crap is a real thing of the past. Now it is about the best value for the money.

For me, I come at it from the aspect of quality of the parts. Does manufacturer even MEET the TDP standards? See, that is the thing that people fail to realize. These companies building AR don't even come close to meeting the TDP spec (let alone advancing them).



C4

FiveSeven
11-30-2011, 9:17 AM
For those interested, Mike Pannone of CTT did a great write up on the M4 and it reliability.

The Big M4 Myth: ďFouling caused by the direct impingement gas system makes the M4/M4A1 Carbine unreliable.Ē
http://www.defensereview.com/the-big-m4-myth-fouling-caused-by-the-direct-impingement-gas-system-makes-the-m4-unreliable/



C4

Very good read. Thank you.

Don29palms
11-30-2011, 10:27 AM
From what I've read, there are advantages and disadvantages to both. So you've never owned a GPU? Do you even own an AR at all?

Primary piston advantages:
-(very arguably) reliability of the weapon, particularly involving feeding and ejecting
-less carbon wear on the bolt (which is irrelevant if your piston system sheers off the screws holding it to the BCG) What bolts are you talking about?
-"easier to clean". well, you're going to be cleaning something. gas piston without a doubt are much easier to clean.

Primary DI advantages:
-Cost $250-$350 less expensive
-Simplicity (less to go wrong)
-Availability of replacement parts (in case something does go wrong)

Look at it this way: If you have a budget, you might as well stick with DI. There is a reason it's still being used in the military. If your bolt goes bad because you're too lazy to clean it, that's $100-$200, and it will take a while to happen. And a BCG is pretty readily available.

On the other hand, if a piston system goes bad, you have to wait a while. If it's got a warranty, you'll be down a few weeks. If it doesn't, then you're paying to replace whatever is damaged. And the parts aren't cheap, if the original 250-350 price tag has anything to say. WHAT? WRONG

Many people say that the piston systems have less FTF and FTE, but if that comes at the cost of your bolt... (most piston systems place the strain from the piston onto a couple of screws on your bolt; sheer those bolts off, and you've usually got to buy a new one). What in the hell are you talking about?

Cleaning is irrelevant, because you have to clean either one. If anything, the piston requires you to clean more parts, because you still have some carbon buildup on the bolt, in addition to the piston system. Wrong again.

If you want to go piston anyway, the Adcore B.E.A.R. seems to have fixed most of the original problems with the piston (sheering of bolts, recoil) and may be something to look into.. but it's about $900 for the upper by itself.

I have to agree with the more experienced people on here, DI is the best way to go for now. maybe in the future, the piston system will be 'perfected'. Good luck (:

You need to read alot more. Your assumptions are mostly wrong.

jkonquer
11-30-2011, 10:47 AM
im not gonna get into technicality of piston vs DI. but i do know fact that piston guns do run cleaner and has a less of maintenance. but the failure will only began after 10k rounds or more with constant shooting. Us average joe won't able to use it enough to care. like any gun, as long as you take care of the gun, any gun will treat you nice.

now lets talk about price.
on average price difference between piston and di is about 200 bucks considering they are same gun with same accessories. So personally i would rather spend the extra 200 bucks to get something newer and cleaner system.
as far as stag m8 goes, its not much of bargain. m8 is a base model, with quad rail, better stock and etc you are looking around 400+ extra bucks.
you can pick up a brand new sig516 for 1300 bucks where as m8 with quad rail is about 1400.

jkonquer
11-30-2011, 10:51 AM
and also, look into different types of piston system. not every company is the same when it comes to gas piston. some are easier to clean and some require complete reassemble. companies like sig sauer, lwrc, adams arm. are good example of a good(in terms of idea) gas piston system.

Outta Control
11-30-2011, 11:04 AM
...failure will only began after 10k rounds or more with constant shooting...

Got any documentation on? Where and what is the failure?

Outta Control
11-30-2011, 11:07 AM
From what I've read, there are advantages and disadvantages to both.

Primary piston advantages:
-(very arguably) reliability of the weapon, particularly involving feeding and ejecting
-less carbon wear on the bolt (which is irrelevant if your piston system sheers off the screws holding it to the BCG)
-"easier to clean". well, you're going to be cleaning something.

Primary DI advantages:
-Cost $250-$350 less expensive
-Simplicity (less to go wrong)
-Availability of replacement parts (in case something does go wrong)

Look at it this way: If you have a budget, you might as well stick with DI. There is a reason it's still being used in the military. If your bolt goes bad because you're too lazy to clean it, that's $100-$200, and it will take a while to happen. And a BCG is pretty readily available.

On the other hand, if a piston system goes bad, you have to wait a while. If it's got a warranty, you'll be down a few weeks. If it doesn't, then you're paying to replace whatever is damaged. And the parts aren't cheap, if the original 250-350 price tag has anything to say.

Many people say that the piston systems have less FTF and FTE, but if that comes at the cost of your bolt... (most piston systems place the strain from the piston onto a couple of screws on your bolt; sheer those bolts off, and you've usually got to buy a new one).

Cleaning is irrelevant, because you have to clean either one. If anything, the piston requires you to clean more parts, because you still have some carbon buildup on the bolt, in addition to the piston system.

If you want to go piston anyway, the Adcore B.E.A.R. seems to have fixed most of the original problems with the piston (sheering of bolts, recoil) and may be something to look into.. but it's about $900 for the upper by itself.

I have to agree with the more experienced people on here, DI is the best way to go for now. maybe in the future, the piston system will be 'perfected'. Good luck (:

So Much FUD! You gotta love.

jkonquer
11-30-2011, 11:15 AM
Got any documentation on? Where and what is the failure?

check out the youtube video of sig516 torture test. they were able to shoot 12k rounds without any failure

Outta Control
11-30-2011, 11:29 AM
You are identifying a specific type of piston system and it doesn't cover all of them. You link the youtube for us.

h0use
11-30-2011, 1:10 PM
I own a gas piston ar and a DI ar and see no difference... Bolt stays clean in the gas piston vs DI bolt but the gas piston gets dirty...

ScottsBad
11-30-2011, 1:20 PM
Hi, I didn't have time to read all the replies to your question, but the bottom line is that you are far better off buying the best quality DI rifle you can get, over buying the least expensive piston rifle just to get a piston rifle.

HERE IS WHAT I'VE LEARNED

I have high-end AR DI rifles, and piston rifles, and what I've learned from owning and building rifles is that I like the DI rifles as much as I do the piston rifles. Right now I'm building my fourth DI rifle. I also, own FN SCARs, and Rugger SR556, but I still enjoy my ARs too.

The hassle of cleaning a DI rifle is not nearly as bad as I thought it would be. And the reliability has been outstanding. When using my piston rifles I still have to clean the piston and while its not as hard to do as cleaning a DI bolt neither is that difficult or time consuming.

MY RECOMMENDATIONS (IMHO)

A lower quality piston rifle will be less durable and reliable than a better quality DI rifle. The key components are the bolt carrier group, the barrel/gas block, the fire control group, then the buffer spring and tube.

The BCG is the heart of a DI rifle, get the best you can get. It should be shot peened, magnetic particle inspected, high pressure tested, and with a staked gas key. Don't compromise on this, it is critical. Right now I use the BCM bolt carrier group, but if you are buying an assembled rifle just make sure its up to snuff.

Next barrels; The best barrels from a durability standpoint are hammer forged chrome lined MID-LENGTH, with a taper pinned gas block. The issue of barrel accuracy is more complex and I won't go there. Most decent AR barrels are reasonably accurate. Chrome lining helps barrel durability, longevity, and aids cleaning. Hammer forging increases durability. Stainless barrels are nice and mine

Mid-length gas systems are the way to go these days. A mid-length gas system rifle will be more reliable and reduce felt recoil a bit over a shorter carbine length gas system.

It is not necessary to have a hammer forged barrel, or chrome lining, but chrome lining will be more immediately useful. Don't get a barrel that doesn't have a really secure gas block, taper pinning is the best (not just pinned, but taper pinned).

I recommend a 16 inch barrel for your first or primary rifle. A 14.5 inch will have a welded flash hider which makes very very difficult to replace the flash hider or add a rail system. A 16 inch is a good compromise between handling and bullet velocity.

Next fire control group; These days most lower receivers are a well made, but the fire control groups (hammer, sear, trigger, springs, selector) vary a lot. The good news is that if you want to upgrade it is relatively cheap to do so later. So I would worry less about the fire control group, but just make sure it is mil-spec.

Next the buffer spring and buffer tube; Most people don't really concern themselves too much with this, but it is one of the most important aspects of a smooth running rifle. Again, the parts are relatively cheap so they can be upgraded later. But the things to know are that a spring is not just a spring. There are good quality springs that will last 10 thousand plus rounds and springs that get weak within a short period. Just make sure the buffer tube is mil-spec diameter (not commercial diameter), and the buffer is an "H" buffer (or a little heavier) for a mid-length gas system. then you can buy a decent spring like a Wolff, or high end springs like a SpringCo "blue". A proper selection of spring, buffer and tube can make your rifle more reliable, smoother shooting, and mechanically quieter.

If you want to "roll your own" Palmetto State Armory has what looks like a great deal on pretty good quality kits (on paper, I don't own one) for a very reasonable price. http://palmettostatearmory.com/8980.php The 16" mid-length with a FN hammer forged chrome lined barrel looks like a winner for a starter rifle.

Cheers---

hnoppenberger
11-30-2011, 1:20 PM
This is false.

Here are the issues with ANY piston system:

1. Cost
2. Weight
3. Felt Recoil
4. Accuracy loss
5. Parts availability
Go to some carbine schools with your piston guns, have something break or fail and see if anyone in the class has that part. ;)
If you want a piston gun, buy from that was designed FROM THE GROUND UP around the piston. This would firearms like the SCAR, AK, etc.
C4

And with thats lets close this thread. Further discussion is simply mindless loss of bandwidth.

Rebellious
11-30-2011, 2:46 PM
Cliffnotes

Both are reliable
Both are accurate
D.I. runs dirtier then Piston
Piston is slightly heavier then D.I.
Piston costs more then D.I.

Enjoy, either choice is a good one. The one you choose will be the best choice.

Outta Control
11-30-2011, 2:56 PM
Cliffnotes

Both are reliable
Both are accurate
D.I. runs dirtier then Piston
Piston is slightly heavier then D.I.
Piston costs more then D.I.

Enjoy, either choice is a good one. The one you choose will be the best choice.

Good wisdom here. If you like a piston AR then go for it. Don't listen to the Anti's.

jkonquer
11-30-2011, 2:56 PM
correction on sig516, it shot 20k rounds without cleaning and failure
http://youtu.be/y32fEQlGqL4