The infamous DI vs. Piston Dilemma - DD M4V7 or LWRC M6A2 SL

[bsumoba]

This is not a DI vs Piston question...it is simply a which one out of these two you would get. Looking at the spec sheets, everything is practically identical with the exception of the Piston/DI systems. Daniel Defense has a nicer rail, but LWRC comes with sights. LWRC has the nickel-boron finishing while the DD will come with chrome (if I get a DD). Price is about the same (+/- $200 dollars?). DD will come with the upgraded Geiselle(?) trigger while LWRC will come with whatever they give me.

Going to use this for sub-200 yd shooting. Target shooting, maybe run-n-gun, HD of course.

Let me add something else...I compromised with the wife on getting my own AR in exchange for the agreement that I will not purchase another firearm until we finish renovations on the house. I estimate that I will not make another purchase for a couple years. I currently have the following:

• M+M M10 762 AK Variant
• S&W M&P15 Sport
• 10/22 Ruger
• Remington 870 Tactical Express Shotgun
• S&W 686 SSR
• CZ 75 SP-01 (tricked out)
• CZ 75 P-01 (tricked out)

Here are some of the basic characteristics of the ones I am debating. I will be adding a bad-*** optic to it.

Looking to spend less than $3K with optics, taxes, etc. Thinking of an Aim or Eotech. I might want to have a QD Mount for glass optics.

Characteristics: DD / LWRC
Caliber: 5.56 NATO
Barrel Length: 16.0" / 16.1"
Barrel Finish: Chrome / NiCorr
Bolt: Chrome / Nickel-Borron
Weight (unloaded): 6.4lbs / 6.4lbs
Rifling: 1/7" RH
Trigger: Geissle SSA / LWRC Std
Bolt: Chrome / Nickel-Boron
Stock/Pistol Grip: DD Modular / Magpul
Sights: MBUS / DD A1.5 Style Fixed Rear; A-Frame Front
Muzzle Device: DD Flash Suppressor / A2 Birdcage 1/2x28 TPI
Price: $1600 (est) / $1576.00 (mparms.com)

[Mossy Man]

i personally dont see the point in a piston AR

[sprig]

I am a huge LWRC fan, so nice cleaning it after a range trip. Love the fit and the feel. I have .223, 6.8 and the .308.

[SB1964]

Pistons are overrated, IMO. Get the DD, you`ll be happy.

[Jyruiz]

I would go DD, if for some reason something broke or malfunction in the field, you can take parts out of the M&P to get your DD working, and vise versa.

[ParanoidCivilian]

Why not stock up on thousands of rounds of ammo? You already have a S&W M&P15 Sport.

[bsumoba]

Originally Posted by ParanoidCivilian

Why not stock up on thousands of rounds of ammo? You already have a S&W M&P15 Sport.

The M&P 15 Sport is the wifey's actually. Last time out, she let me shoot 3 rounds out of the 120 rds we brought to the range. She absolutely loves it and wants to duracoat it to a color of her liking.

Thus, the reason I want my own and I want to keep it all black because its "evil" as broadcasters and anti-2A people tend to say. Speaking of which and not to get off on a tangent, but I heard on the news that a guy shot his dad with an arrow and then pulled a knife on himself. I guess you don't need a gun to be dangerous. OK, I'm done with my ranting.

http://www.examiner.com/article/bow-...her-stabs-self

Back to the actual question...she wants to keep it all stock (I actually put a Vortex Strikefire red dot so she can co-witness) and I hate keeping things all stock.

I also have a good amount of ammo already and do plan on getting more.

[dingle_berry]

My 2cents, get the LWRC. If you're looking to expand your collection, and already have the M&P, my vote is to buy something different.

[Quiet]

Direct Impingement.


The following quote is from a former SFOD-D operator who served for over 20 years...

Originally Posted by Larry Vickers

Piston AR's have their place- to determine if you need one ask yourself four questions;

1) Do I need a barrel length shorter than 14.5 inches
2) Do I need to run my gun suppressed a lot
3) Do I need to shoot a lot of full auto
4) Do I need to shoot a wide variety of ammo

Piston guns have been shown to be superior in those four categories over a DI gun. If you can say no to all four questions a good DI gun will do you fine

[bsumoba]

Good input everyone. I am about 90% settled on the DD. Waiting from my local FFL if he can order a "Build Your Own" DD (check DD's website. Pretty nifty) and leadtime and cost. I will keep everyone posted on what I choose

[rojocorsa]

Daniel Defense.

[calishine]

LWRC

[ar15barrels]

Daniel Defense.

[BBB114]

Both are great guns. I teach alot of carbine classes and these run great, all the time. I am a fan of both. In this instance, I would choose the Daniel Defense. I love the LWRC, but the one you are looking at is on their low end and I think the Daniel Defense will give you more bang for the buck. Unless you just HAVE to have a piston gun.......stick with DI.

Boyan

[Riddler]

[mlevans66]

I really like the look and feel of the LWRC but when it comes down to parts then DD. Also the LWRC will be heaver and less cleaning will be required but if you are used to a DI and using a DI then I say get the DI.

Anyway...Im for the DD.

[bsumoba]

Alright...so if I compare a DD M4V7 (custom) with a LWRC M6A2, which one would you choose from these?

Reason being, the M6A2 will have Troy Sights, a little more of an upgrade from the SL version. The difference in cost will ultimately be $200-300 dollars once I put in the things I want in the DD such as a chrome bolt upgrade, trigger upgrade, and BUIS.

[HK Dave]

Choose Daniel Defense

The AR15 was NEVER intended and NOT DESIGNED to work with a piston system.

If you understand how an AR works, and have a basic understanding of the law of physics, you'd know that if you wanted a Piston rifle, it would be something designed around the piston... like a SCAR.

Now if LWRC made a DI gun... I'd be highly interested... well minus their sticker price.

[HKDoc]

Whatever you get, Peter at Mpa arms is a great guy to work with. Either choice would be good. Lmt piston not an option? He carries those too.

[bsumoba]

Originally Posted by HK Dave

Choose Daniel Defense

The AR15 was NEVER intended and NOT DESIGNED to work with a piston system.

If you understand how an AR works, and have a basic understanding of the law of physics, you'd know that if you wanted a Piston rifle, it would be something designed around the piston... like a SCAR.

Now if LWRC made a DI gun... I'd be highly interested... well minus their sticker price.

I did a fair amount of research on this and I do keep coming back full circle on a DD.

Thanks everyone for your help. I am set on DD (unless somehow I can get a Larue PredatAR or OBR) I'll slap on a nice Comp M4s on it and call it a day

[HK Dave]

Ah... if the Larue was part of the choice, I'd go Larue...

I made it easy on myself and just got both. :P

[whlgun]

LWRC for the win. Just got an M6 - SL. Its very light and fit and finish are outstanding. Never owned a DD but I have never heard anything bad about them.

The AR15 may have never been intended or designed for a piston system but it happened anyway so get over it DI fans. They are both great systems. I don't understand why you guys bash pistons so much.

[HK Dave]

Not bashing piston systems, I think pistons are great. I just don't think they're great in an AR.

[whlgun]

Originally Posted by HK Dave

Not bashing piston systems, I think pistons are great. I just don't think they're great in an AR.

Why are they not great in an AR design?

Are they too heavy for you?
Are they too innacurate for you?
Are the parts so hard to find?

My piston AR's do weigh more. When im shooting do I notice it.NO

Most piston AR's are not made for bench rest shooting so I guess the bench shooters should stay away. Most AR's piston or other will out shoot the shooter. None issue in my book

Parts are terribly hard to find I have to go online and order them. They are more expensive but I have no problems going on LWRC and ordering them.

The piston VS DI debate is the same as the AK vs AR debate. A hole bunch of fanboy misinformation.

Not calling you out HKdave just saying they are both great platforms.

[ar15barrels]

ARs and AKs are both platforms, but don't try to mix them.

The round bore receiver and bolt carrier of the AR is not a good design for an off axis force piston system. Note that the AK carrier runs on rails.

[NYT]

lwrc is without a doubt the finest piston driven system on the market with fantastic customer service.

dd is a very good all around rifle but couldn't hold a candle to the lwrc... and I have a dd rifle.

if you can stand the wait get the piston.

Sent from my Galaxy Nexus using Tapatalk 2

[SOCAL-PRINCE]

+1 for LWRC and Peter from MPArms. I purchased my M6A2 in OD Green from him and it is the best AR I own. Accurate, reliable, easy as hell to clean, and the fit and finish is beautiful.
You will hear a lot of Piston vs. DI opinions but see the pros and cons for yourself. The DI system served me well in the Army but I am a firm believer in the piston system. Just my .02..... I think you'll be happy either way.

[Colt-45]

Originally Posted by whlgun

LWRC for the win. Just got an M6 - SL. Its very light and fit and finish are outstanding. Never owned a DD but I have never heard anything bad about them.

The AR15 may have never been intended or designed for a piston system but it happened anyway so get over it DI fans. They are both great systems. I don't understand why you guys bash pistons so much.

You think people here bash on piston systems? You must no be very familiar with m4carbine. You wont know piston bashing until youve visited that website.

Regardless of what forum you're on though piston vs. di threads never end well.

Originally Posted by BBB114

Both are great guns. I teach alot of carbine classes and these run great, all the time. I am a fan of both. In this instance, I would choose the Daniel Defense. I love the LWRC, but the one you are looking at is on their low end.

Nothing low end about the m6-sl. Its just the skinny barrel version with front post sight. Basic, yes, low end, no.

[whlgun]

Originally Posted by ar15barrels

ARs and AKs are both platforms, but don't try to mix them.

The round bore receiver and bolt carrier of the AR is not a good design for an off axis force piston system. Note that the AK carrier runs on rails.

Seems to work fine in my Adams Arms and my LWRC.

[BMWguy206]

My first AR15 was a Daniel Defense. After numerous rifle/carbine courses, I sold the DD and got a gas piston upper. I am very happy with the setup but if were to get a second AR15, it would be a DI (DD or Noveske) just so that I can have both setups.

[Agent Tikki]

Originally Posted by whlgun

Why are they not great in an AR design?

Are they too heavy for you?
Are they too innacurate for you?
Are the parts so hard to find?

My piston AR's do weigh more. When im shooting do I notice it.NO

Most piston AR's are not made for bench rest shooting so I guess the bench shooters should stay away. Most AR's piston or other will out shoot the shooter. None issue in my book

Parts are terribly hard to find I have to go online and order them. They are more expensive but I have no problems going on LWRC and ordering them.

The piston VS DI debate is the same as the AK vs AR debate. A hole bunch of fanboy misinformation.

Not calling you out HKdave just saying they are both great platforms.

You have good points. I would just like to add, that in my personal opinioin the benefits of a piston don't justify the added expense. I would still consider a piston if I was looking to shoot corrosive ammo, or was planning on taking it swimming.

I'd much prefer something like a LaRue OBR.

[whlgun]

Who wouldn't want a LaRue OBR.

[ZX-10R]

DD...LWRC for the price is not worth it IMO...My buddy has one and though it was a good shooter it did not best my DD.

[Colt-45]

As far as weight is concerned, the M6A3 is heavy as hell for a 5.56 rifle, on the other hand the M6-SL and the M6A2-SPR with fluted barrel are a hell of a lot lighter. Not just my opinion, opinion of other people who have handled my SPR as well.

We can't group all piston rifles in the same group, not everyone has put the same amount of time and money into research and development. A fail of one brand shouldn't encompass all piston rifles. I have both and shoot both. I do not subscribe to the "pistons are less accurate" theory, this theory applies if you have a cheap piston conversion on a ****ty barrel or bought a rifle from companies that half assed their piston designs (wont say any names so I don't hurt anyone's feelings).

LW's original piston design offered nothing to the AR platform(except MORE weight) and wasn't very reliable. They also had ****ty customer service, alot of people on M4carbine haven't let this go to this day even though its no longer the same company. LW changed ownership and became LWRC International, vastly improved their design and customer service. LWRC has been tested in the field, DEA agents in Afghanistan liked their M6A2's but the REPR failed, it had problems with the magazine/lower receiver(problem wasn't the piston). The issue has been corrected since then.

Fail after fail, people still believe in Centry Arms International and their WASRS, LWRC has had far less fails, why should we turn our back on them?

I believe in LWRC as much as I believe in BCM and Noveske. DD is also an excellent firearms manufacturer, for what you're getting with each and the price range I'd have the same issue picking between the two like the OP did in the very begging before he leaned DD.

For that price, I'd get both obviously one now and one down the road. The deal breaker for me between the ops two options is the Geissele trigger, if the DD didn't come with the Geissele I'd have an easier time picking but since the DD has the Geissele, I believe the deal is dead even.

Originally Posted by Agent Tikki

I would still consider a piston if I was looking to shoot corrosive ammo, or was planning on taking it swimming.

Good one.

[HK Dave]

Originally Posted by whlgun

Why are they not great in an AR design?

Are they too heavy for you?
Are they too innacurate for you?
Are the parts so hard to find?

My piston AR's do weigh more. When im shooting do I notice it.NO

Most piston AR's are not made for bench rest shooting so I guess the bench shooters should stay away. Most AR's piston or other will out shoot the shooter. None issue in my book

Parts are terribly hard to find I have to go online and order them. They are more expensive but I have no problems going on LWRC and ordering them.

The piston VS DI debate is the same as the AK vs AR debate. A hole bunch of fanboy misinformation.

Not calling you out HKdave just saying they are both great platforms.

Hehe, I've spelled this out on many many occasions... but I will do it against, just for conversation sake.

Let's talk about the DI AR...

It has a BCG that connects to a gas tube... when the gun is fired, gases travel through the gas tube, into the bolt, into the center of the bolt, and the round bolt transfers straight back into the buffer tube.

Frankly, the design is genius and way ahead of its time.

Let's talk about the Piston AR....

It has an OP Rod, or a piece of metal that moves after the gun is fire, that then smacks the upper front part of the BCG, transferring its energy from the front top of the BCG to the bottom rear the carrier creating friction and un-needed recoil from the OP Rod movement. It doesn't matter that they added rails or whatever... physics dictates that friction is being cause period.

I've heard the argument that the Piston is cleaner where it eats... provided it isn't suppressed, that is true, however, it's filthy where the OP Rod gets its gas to operate. So it still gets dirty, just in a different place.

The argument that a Piston will run longer and better is moot, when it is a well known fact that a DI AR will run forever as long as its lubricated. Frankly I don't think most folks will run 5K rounds without cleaning ANY gun... but there are a few crazies out there.

So... with all things being equal, two of the exact same rifles, one DI, one Piston, the Piston has the disadvantage of being heavier, or having a proprietary part and changing the recoil pulse of the rifle and quite possibly the barrel harmonics. The DI has the disadvantage of crapping where it eats... but that doesn't stop it from working... and working well.

Piston ARs are produced for the civilian market for one reason, and one reason only... because by adding a $50 part, they can charge you $500 more for it. It's marketing at it's best.

Understand, I'm not a fanboy of DIs... matter of fact, I prefer shooting bolt guns and yes, I do enjoy benchrest over run and gun.

However I own 7-8 ARs... a couple of them cost much more than the LWRC. I chose them not because of price, not because I'm a fanboy but because I've done the research, and I find no reason to put a Piston in an AR.

Ask yourself this, why doesn't Larue, Noveske, JP have piston ARs?

[HK Dave]

BTW, this is not to say that LWRC doesn't make great guns... I think they're one of the best AR manufacturers out there... I just don't think the Piston is necessary and i refuse to pay extra for it.

Now a SCAR on the other hand, I'd happily pay for that piston.

[Dhena81]

I have to admit I think its funny that one of the supposed pro's of owning a piston AR is the lack of carbon build up in the upper receiver.

[whlgun]

Originally Posted by HK Dave

Hehe, I've spelled this out on many many occasions... but I will do it against, just for conversation sake.

Let's talk about the DI AR...

It has a BCG that connects to a gas tube... when the gun is fired, gases travel through the gas tube, into the bolt, into the center of the bolt, and the round bolt transfers straight back into the buffer tube.

Frankly, the design is genius and way ahead of its time.

Let's talk about the Piston AR....

It has an OP Rod, or a piece of metal that moves after the gun is fire, that then smacks the upper front part of the BCG, transferring its energy from the front top of the BCG to the bottom rear the carrier creating friction and un-needed recoil from the OP Rod movement. It doesn't matter that they added rails or whatever... physics dictates that friction is being cause period.

I've heard the argument that the Piston is cleaner where it eats... provided it isn't suppressed, that is true, however, it's filthy where the OP Rod gets its gas to operate. So it still gets dirty, just in a different place.

The argument that a Piston will run longer and better is moot, when it is a well known fact that a DI AR will run forever as long as its lubricated. Frankly I don't think most folks will run 5K rounds without cleaning ANY gun... but there are a few crazies out there.

So... with all things being equal, two of the exact same rifles, one DI, one Piston, the Piston has the disadvantage of being heavier, or having a proprietary part and changing the recoil pulse of the rifle and quite possibly the barrel harmonics. The DI has the disadvantage of crapping where it eats... but that doesn't stop it from working... and working well.

Piston ARs are produced for the civilian market for one reason, and one reason only... because by adding a $50 part, they can charge you $500 more for it. It's marketing at it's best.

Understand, I'm not a fanboy of DIs... matter of fact, I prefer shooting bolt guns and yes, I do enjoy benchrest over run and gun.

However I own 7-8 ARs... a couple of them cost much more than the LWRC. I chose them not because of price, not because I'm a fanboy but because I've done the research, and I find no reason to put a Piston in an AR.

Ask yourself this, why doesn't Larue, Noveske, JP have piston ARs?

Piston AR's are made for the civilian market because consumers want what the military and police have. Just look at BCM. Everyone finds out that they are made for the military market and everyone buys them up. Including myself.

I don't know why those companies don't make a piston and I don't care. Many companies are now offering piston designs including Colt. Because other companies did it does that make it better then a DI? Answer is no so what is your point?

To say that a rifle that doesn't run cleaner isn't more reliable is ludacris. My piston op rod doesn't get caked with carbon like you would expect. It does run cleaner and although it isnt a huge difference what matters is the bolt stays clean. The parts that matter stay clean and to me that is a huge advantage. Is it a big enough deal? That is for each individual to decide but i personally like it. I don't mind that people don't see the advantage to the piston. I mind all the BS that people spew about it.

[ar15barrels]

Originally Posted by HK Dave

It has an OP Rod, or a piece of metal that moves after the gun is fire, that then smacks the upper front part of the BCG

And THAT is where the AR implementation of the gas piston fails compared to the AK implementation.


The AK piston is directly linked to the carrier at all times.
There is no smack.
In fact, since the AK piston is also rigid, the piston head itself IS the anti-tilt feature for the bolt carrier group.
Think about how long the AK op-rod and piston are and you see that it's not possible for the AK carrier to tilt.

The next thing that makes the AK piston design better is that they put the spring right in the middle of the op-rod, like on a Garand or M1A.
That means that the operating force is directly in line with the spring, just like a a direct impingement AR.
When the operating force is inline with the operating spring, there is no tendency for the carrier to tilt.

So, the main reasons that gas pistons do not belong in the AR platform is that the operating spring is NOT in line with the action operating force.
The Daewoo DR200 and the Robinson Armanent XCR are exceptions to this rule as they both have operating springs in line with the piston and they use AR fire control group and AR magazines.

[whlgun]

Originally Posted by Dhena81

I have to admit I think its funny that one of the supposed pro's of owning a piston AR is the lack of carbon build up in the upper receiver.

The idea is that the carbon is not on the bolt.