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Hallz
09-18-2012, 12:50 AM
A month ago I decided I would finally make the plunge into the AR field.

So, today I stopped by a LGS and started picking up a few items so I can start the build. Since I am a newbie, feedback on what I should expect and lookout for is appreciated.

This will be for hunting and mid-range shooting. Probably nothing over 600yards with the 16.

Goal, light/med weight 308 usually fired under 300 yards. Keeping it under 9lbs would be great.

http://i7.photobucket.com/albums/y286/BenDover666/lr3082s.jpg

CMMG lower
DPMS LR-308 16" Oracle upper
DPMS lower parts kit (308)
DPMS buffer tube (spring & buffer)
Noveske quick detach end plate
Geissele SSA trigger
Magpul MOE hand guard
Magpul STR stock
Magpul MIAD grip
Magpul MBUSS sight (r)
Magpul MS3 sling


Please keep in mind this will be my first AR and I have so much to learn.
Did I miss anything?

scglock
09-18-2012, 1:00 AM
Personally I'd go with an 18 or 20" barrel but thats all personal preference. You should look into the geissele match triggers too. I think that would be a better option but the ssa will suffice. Also a bipod if you want. But looks like it will be a nice build.

MrPlink
09-18-2012, 1:55 AM
Under 9lbs huh?

Hallz
09-18-2012, 12:06 PM
Plink, do you think it's possible or going to be a big challenge?
Any sugguestions as to we're I can save weight?

P.Charm
09-18-2012, 12:08 PM
Personally I'd go with an 18 or 20" barrel but thats all personal preference. You should look into the geissele match triggers too. I think that would be a better option but the ssa will suffice. Also a bipod if you want. But looks like it will be a nice build.

I'd go with an 18" also. my future...way future .308 will be 18"

Hallz
09-18-2012, 1:31 PM
What advantage will the 18" give me at 75-400 yards?

MrPlink
09-18-2012, 1:49 PM
I think under 9lbs should be doable if you have no plans for optics. A light profile barrel will help, but if you are shooting for groups at 600yds this wont be an ideal set up.

connorr931
09-18-2012, 2:06 PM
One of the biggest ways to save weight is the barrel. I would perfer a fluted. Take a look in the AR308 Picture thread, it will give you lots of ideas. My first AR was also a .308. Your gona love it!

robert101
09-18-2012, 2:18 PM
My first AR type was also a 308 with a DPMS TAC20 upper. I used a TM lower and have no regrets. My barrel is a medium so the profile is heavy. I don't see a problem with the lighter barrel at all. Great choice and you will have so much fun with the 308.

wash
09-18-2012, 2:58 PM
With a .308, the advantage of a long barrel is less muzzle blast.

It takes more than 21" to get a complete burn without very much flash.

You can go short but you lose velocity and add a bunch of muzzle blast.

An Ace Skeleton or Ultralite fixed stock might save some weight, then look at the barrel.

I think AR15Performance has some light weight DPMS pattern barrels in stock, they should be nice.

MrPlink
09-18-2012, 3:05 PM
You can go short but you lose velocity and add a bunch of muzzle blast.



yep, but if OP intends to keep it at 300yds with the occasion 600yd max 16in should be fine.

wash
09-18-2012, 3:17 PM
And so would 20" with much less muzzle blast.

Hallz
09-18-2012, 3:50 PM
If the additional weight of going to a longer barrel will not improve the accuracy of the initial shot and add weight, I will stick with a 16" for this build.

I will be looking into the fluted and upto 20" barrels for future. The fixed skeleton stock is something to look into!

bob_e95482
09-19-2012, 3:45 AM
My DPMS/TM10 build has an 18" bull barrel with no muzzle device. This rifle is barely an inch longer than my M4gery. I used the DPMS free floated upper that has no forward assist or dust cover, it was $750 through Midway/USA. I also have the SSA trigger. It takes a few shots to get used to the 2 stages, but is a lot lighter pull than the trigger that came with the DPMS LPK. Mine is a heavy rifle. I have a bipod and Leupold scope and use it for bench shooting, out to 500 yards.

Hallz
09-19-2012, 8:32 PM
Bob,
Do you ever wish you would have went with an upper that had the forward assist and dust cover?

I only hear good about the SSA

Hallz
10-02-2012, 1:08 AM
Updated with pic.

8.4 lbs, so far so good. Now to figure out what front gas block sight and optics.

SoCalXD
10-02-2012, 9:25 AM
Updated with pic.

8.4 lbs, so far so good. Now to figure out what front gas block sight and optics.

Ah yes, front sight, 1-4 optic, optic mount, butler creek covers... welcome to the 10.5lb rifle! Oh, a good padded sling (VTAC) and a Harris Bipod... make that an 11.5lb rifle!

Since you went with a short barrel, no real "need" for optics out to 300, keep it fast and light without optics, or you could go cheap and slap a low weight PA Red Dot on there to add a little speed on target. Otherwise, plan on spending +/- $500 for a good 1-4x Optic solution.

If you post a photo with a 5-20x scope on that 16" barreled rifle, WASH tells me you are banned from the Calguns LR308 Club! ;)

starsnuffer
10-02-2012, 9:29 AM
Ok so you're going to put an optic on it. My first thought was with a light rifle you were going to use irons only with a really short sight radius, but since the irons will just be backup it shouldn't matter much.

Honestly you should have bought a SCAR 17, but it's cool you're building your own toy and I'm interested in seeing how it turns out.

-W

9-12
10-02-2012, 9:42 AM
What advantage will the 18" give me at 75-400 yards?None. I have a 16" that will hit plates at 600 with no problem and I've shot out to 800 with it. (Effective range of the .308 is only about 800yds) My 16 is a better barrel, but barrel length has little to do with accuracy. For your use, the 16" is fine. I'd put a 3x9 optic on it for hunting. 300yd shots should be a walk in the park if you're any kind of shooter.
JMO

chozenfew805
10-02-2012, 9:52 AM
Looking good so far but I'm tagging this post to see what you end up with!

IPSICK
10-02-2012, 9:58 AM
Ok so you're going to put an optic on it. My first thought was with a light rifle you were going to use irons only with a really short sight radius, but since the irons will just be backup it shouldn't matter much.

Honestly you should have bought a SCAR 17, but it's cool you're building your own toy and I'm interested in seeing how it turns out.

-W

This DPMS will outshoot a SCAR any day and every day.

Damn True
10-02-2012, 10:29 AM
A month ago I decided I would finally make the plunge into the AR field.

So, today I stopped by a LGS and started picking up a few items so I can start the build. Since I am a newbie, feedback on what I should expect and lookout for is appreciated.

This will be for hunting and mid-range shooting. Probably nothing over 600yards with the 16.

Goal, light/med weight 308 usually fired under 300 yards. Keeping it under 9lbs would be great.


CMMG lower
DPMS LR-308 16" Oracle upper
DPMS lower parts kit (308)
DPMS buffer tube (spring & buffer)
Noveske quick detach end plate
Geissele SSA trigger
Magpul MOE hand guard
Magpul STR stock
Magpul MIAD grip
Magpul MBUSS sight (r)
Magpul MS3 sling


Please keep in mind this will be my first AR and I have so much to learn.
Did I miss anything?

Do you mind sharing what you have into it at this stage?

Anchors
10-02-2012, 2:17 PM
Haha dude I love the "NO FIREARMS" sign. I need to get a "gun free zone" sign for my safe.

FeuerFrei
10-02-2012, 4:14 PM
Only thing I would add is an adjustable gas block & McFarlen gas rings on the bolt. 16" bbl will do what you want.


Sent with 2 cans & a long string.

wash
10-02-2012, 5:46 PM
If you post a photo with a 5-20x scope on that 16" barreled rifle, WASH tells me you are banned from the Calguns LR308 Club! ;)

No, he's not banned from the club but he is banned from shooting it in the lane next to me (but it's not because of the scope).

Just kidding kind of but he's ~hurting himself more than anything.

If you are looking at low power variable scopes, Meuller makes one that is cheap and sounds nice, Natchez might have the Weaver Classic Extreme, I have one, I like it but it is a little heavy. Figure at least a pound for the scope and at least 3-4 oz for the lightest scope mount you can find. My Weaver is about 18oz with a ~3oz CAA DVSR mount for about 21oz total.

That's still lighter than most red dot/magnifier setups but my weaver reticle illumination isn't exactly daylight visible but for the price it is still nice.

Hallz
10-02-2012, 7:54 PM
Do you mind sharing what you have into it at this stage?

I am about $1600 give or take $75.

I am thinking a holographic red dot is the way to go first, but looking for a scope down the road.

You'll have to forgive me. I have shot and hunted with iron sites almost my entire life. I have recently placed non magnified red dots on a few of my rifles and really like them.

My concern is that at 200- 300 yards non magnification becomes unethical.
Can you guys give me the straight on what justifies $300+for a HG red dot? If it will hold 0 for the caliber and the dot size is equal why spend 3x the amount? I am not one for over spending just to brag about it.

Thanks!

bomb_on_bus
10-02-2012, 8:04 PM
I didnt notice any sort of front sight to complement the rear sight.

As far as weight goes the optics are going to be the area of focuswithout having to change out anything on the gun. If you can swap out for a flutted barrel that should shave off a few ounces. The stock could be swapped out for a lighter weight model but it won't be much for the effort of looking around and getting another one. Those 2 areas on the rifle could shed some weight to allow a for an optic to be added and keep you close to your weight goal with the gun.

Hallz
10-21-2012, 11:39 PM
Bomb,
I mounted a friends rear sight to see how I liked the Magpuls but decided against them.

Update:
I picked up a Burris Fullfield E1 3x9-40mm (illuminated Ballistic Plex) with the quick disconnect P.E.P.R mount and a Fastfire red dot. Originally I was going to replace the scope on my 300 win mag with the illuminated E1 and put the Fastfire on the AR, but curiosity got the best of me and I mounted it on the 308. Well,..... surprisingly the eye relief was better than most of the scoped I had been using lately (even much higher priced glass) .....and I like it A LOT.

Backed down to 3x it is very similar to a 2x magnified red dot. Tracking targets with both eyes open appears to be easily accomplished. If this is the case I may just leave it on.

http://www.burrisoptics.com/images/ball_plex-E1-reticles.jpg

If so, may be looking for a fluted 20" barrel. As Wash mentioned the muzzle blast is quite significant. I did not notice it shooting but my spotter did and recorded it for me to see.

Anyone know of a muzzle break that is proven to work significantly better than the factory DPMS and worth the cost?

Thanks

Hallz
10-22-2012, 1:55 PM
Are the adjustable gas blocks worth it?

nrakid88
10-22-2012, 2:01 PM
for a scope I would recommend the Bushnell grand slam 3-9 at midwayusa. Not sure if it will meet your needs, but I am in love with it.

FeuerFrei
10-22-2012, 3:00 PM
Are the adjustable gas blocks worth it?

They eliminate "over gass" problems so ammo selection is less critical and less wear and tear on the bcg.
I had a 308 DPMS 16" upper and the thing was blowing primers, throwing brass 8' away and scaring up the bases of the brass.
You can run off the shelf hunting/match ammo as well as reloading. Makes weapon easier to tune for the load without screwing with buffers/springs etc. and still have it cycle reliably.

wash
10-22-2012, 3:45 PM
http://www.ar15performance.com/308_barrel

That's a pretty low price for a quality 18" mid-gas DPMS pattern light weight .308 barrel.

They don't seem to make a light 20".

As for muzzle brakes, any effective brake will give you a big muzzle blast but some are better than others.

As an alternative, I think Magpul makes an enhanced butt pad for your stock (my ACS has one), that will reduce the recoil a bit. Then get a flash hider or a brake with less blast (I've heard of some MSTN "warm breeze" brake but I might have the letters wrong, it's supposed to be effective at reducing recoil without creating much blast, sounds like a unicorn to me but you might try looking for one).

Marinos
10-22-2012, 3:52 PM
They eliminate "over gass" problems so ammo selection is less critical and less wear and tear on the bcg.
I had a 308 DPMS 16" upper and the thing was blowing primers, throwing brass 8' away and scaring up the bases of the brass.
You can run off the shelf hunting/match ammo as well as reloading. Makes weapon easier to tune for the load without screwing with buffers/springs etc. and still have it cycle reliably.

X2
I made the mistake of going with the non adjustable gas block on my AR-10 and my extractor rips the rim off of the casing about every 50 shots. The rest of the ammo it just scars.

Hallz
10-22-2012, 4:06 PM
Wash, that is a good deal, I may have to order it. I already have the Enhanced butt pad, the recoil is not bad

The JP breaks look good but almost twice the price of others.
http://www.jprifles.com/1.4.3_tre.php

May see if they can do this one in 308
http://www.ar15performance.com/inc/sdetail/2121/3382

Hallz
10-22-2012, 4:10 PM
X2
I made the mistake of going with the non adjustable gas block on my AR-10 and my extractor rips the rim off of the casing about every 50 shots. The rest of the ammo it just scars.

I have my spend brass from the first 30 round outing, ill see how they look. The first 5 looked good, the rest I have not looked at yet. Sounds like it may be worth it, can't do any harm right?


Blurry camera phone pics, but not bad IMO.
http://i7.photobucket.com/albums/y286/BenDover666/37A258DE-240A-48AB-9D33-188927DCE45A-10307-00000217A578296C.jpg

http://i7.photobucket.com/albums/y286/BenDover666/CD2D0F80-68D1-4BBD-B237-952999787525-10307-00000217BA832926.jpg

http://i7.photobucket.com/albums/y286/BenDover666/377742E3-03AD-4796-84EB-3B251A6EBBF8-10307-00000217CADEB6E6.jpg

SoCalXD
10-23-2012, 8:11 AM
I think WASH nailed it regarding muzzle brakes and comps. The blast and flash have to go somewhere... it just comes down to where you want to send it. I run the PWS on my rigs; soaks up recoil quite well, keeps the muzzle level, keeps the blast out of the dirt, reduces sound level in front, and on shorter barrels, are way loud behind the muzzle and pisses off everyone next to me on the range! There are no free lunches.

Hallz
10-23-2012, 1:43 PM
I think WASH nailed it regarding muzzle brakes and comps. The blast and flash have to go somewhere... it just comes down to where you want to send it. I run the PWS on my rigs; soaks up recoil quite well, keeps the muzzle level, keeps the blast out of the dirt, reduces sound level in front, and on shorter barrels, are way loud behind the muzzle and pisses off everyone next to me on the range! There are no free lunches.

That works for me, hehehe

Happyhappycamper
10-23-2012, 1:52 PM
Can someone explain to me the adjustable gas block thing? I mean I understand that it controls the gas flow, but to solve what problem?

I keep hearing about extraction issues and such, but have never experienced anything of the sort so my curiosity is piqued.

ire76io
10-23-2012, 2:15 PM
This might be of interest to the OP.

https://snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1527920

Hallz
10-23-2012, 2:36 PM
This might be of interest to the OP.

https://snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1527920

Thanks,
A few real good shooters (and friends) have told me the same, when I go out and shoot with them I will learn a lot! Till then, just soaking up as much as I can.

Happyhappycamper
10-23-2012, 2:43 PM
yea, but you are talking about a $3000 gun with a $1600 optic on it...

Most 16" 7.62's are simply not going to pull off 1000 yard shots like that.

wash
10-23-2012, 2:46 PM
Most commercial .308 ammo is designed for bolt action rifles and the manufacturer could care less about how it functions in a semi-auto.

As a result, the pressure curve isn't ideal for semi-auto.

An adjustable gas block let's you dial back the amount of gas to slow your bolt carrier which means less violent extraction and brass that is less beat up.

If your AR is tuned right and you shoot 7.62*51 NATO spec ammo, everything should work fine with a standard gas block because 7.62*51 was developed for the M14 and FAL which are gas operated semi-auto rifles.

Comercial .308 will mostly not conform to NATO spec and that's why an adjustable gas block will help it run smooth.

Happyhappycamper
10-23-2012, 2:53 PM
Most commercial .308 ammo is designed for bolt action rifles and the manufacturer could care less about how it functions in a semi-auto.

As a result, the pressure curve isn't ideal for semi-auto.

An adjustable gas block let's you dial back the amount of gas to slow your bolt carrier which means less violent extraction and brass that is less beat up.

If your AR is tuned right and you shoot 7.62*51 NATO spec ammo, everything should work fine with a standard gas block because 7.62*51 was developed for the M14 and FAL which are gas operated semi-auto rifles.

Comercial .308 will mostly not conform to NATO spec and that's why an adjustable gas block will help it run smooth.


Thank you, that makes perfectly good sense and was written in a way even I can understand it! :)