.308 AR Platform - DPMS vs. Armalite regarding BCG

[lolnorcal]

In the midst of my build, I'm facing a few questions, primarily concerning the BCG. The DPMS style bolts are clearly more popular and available, while Armalite BCG's are like finding a needle in a haystack. My concern is not only for the time being, but in the future when I may need to source replacement parts.

What I'm essentially asking is- I've been lead to believe that DPMS isn't exactly "top tier" stuff, at least in the AR15 world. At the same time, I don't know how much a BCG will really effect the accuracy of the rifle, if at all. Another member on a different board pointed out a few features on Armalite style BCG's that DPMS ones don't have. I'm having Krieger build my barrel, so whatever option I go with doesn't matter much. Except if I chose the DPMS route, I may actually be able to get a barrel sooner. I've heard good things about Black Hole Weaponry, and they turn a barrel that's to my liking. Heavy profile, fluted, black, threaded, 22" or 24"

Sorry if this post is long, or if the topic has been beaten to death already. Thanks for any comments or suggestions.

The build so far:
Mega Ma-Ten receiver set
Magpul .308 PRS
Geissele SSA-E
SWFA SS HD 5-20x50 w/ Butler Creek Caps
10/20 and "stubby" 10 rnd .308 P-mags

Plan to get:
Troy .308 TRX 13.8"...possibly a JP FF tube, undecided
JP Enterprises large profile Bennie Cooley compensator
Buffer tube/buffer/spring
Gas tube and low profile gas block
American Defense non-cant scope mount
Ergo grip w/ palm shelf

 

[caelumatra]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

I have an Armalite BCG so its all I can comment on. Its heavy. It doesnt have the top cut out like the DPMS or an ar15 carrier does. I don't know how much weight it adds, but it seems to me unnecessary.

Do you have a link to where the differences were posted? I knew they were different somehow but other than that one thing I mentioned I don't know what they are. I'm sure it has to do with the bolt more than the rest of the carrier though because you should use the same pattern bolt/barrel combo.

I bet you could call armalite and see if you could buy a few extra bolts. Or call Noveske, maybe they'll sell you some. DSGarms.com and Rainier is where I buy most of my parts. They may sell you bolts...they may not.

I have a Noveske barrel, so armalite was my limited option for BCGs.

But, JP makes 308 bolts for DPMS though so you wouldnt be stuck with DPMS if you went that route.

http://www.jprifles.com/1.4.7_bc.php

 

[lolnorcal]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

I'll try to find the thread, but I believe it was on arfcom in the Ma-Ten build thread. I can't be completely sure, though.

I was lead to believe that finding an Armalite BCG is fairly difficult. I see that Rainier stocks this item, though it doesn't say whether or not it's in stock. Perhaps I'll call them during business hours. I'd also like to check with the vendor I normally go through. I know the Ma-Ten is designed to use an AR-15 LPK, so I need to do research on whether or not an Armalite AR-10 LPK will work.

Thanks for the link to the JP bolt, but I considered them before and didn't want to pay the premium for it.

 

[powderBurnz]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

762sass had a bunch of ar10 parts when I was deciding whether to go ar10 or dpms-format.

762SASS

 

[caelumatra]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: lolnorcal</div><div class="ubbcode-body">I'll try to find the thread, but I believe it was on arfcom in the Ma-Ten build thread. I can't be completely sure, though.

I was lead to believe that finding an Armalite BCG is fairly difficult. I see that Rainier stocks this item, though it doesn't say whether or not it's in stock. Perhaps I'll call them during business hours. I'd also like to check with the vendor I normally go through. I know the Ma-Ten is designed to use an AR-15 LPK, so I need to do research on whether or not an Armalite AR-10 LPK will work.

Thanks for the link to the JP bolt, but I considered them before and didn't want to pay the premium for it. </div></div>

The way Rainiers website works is, if you can add it to the cart, its in stock. It will have a yellow "Notify Me" button where the add to cart button would be. They do a good job of keeping the website matched to their inventory. DSG's website works the same way. If its not in stock, you cant add it to the cart.

On the AR10 LPK, you pay a little more for it vs the ar15 one. I just put a standard Daniel Defense LPK from Rainier in mine and all is well. The AR10 LPK has different sized take down pins and a different bolt catch. Those are the only differences. But since the MA TEN comes with the take down pins, thats moot and I have an AR10 bolt catch I bought a while back before I discovered the MA TEN and its too big to go in the slot for the bolt catch. But the standard ar15 that came in the DD LPK works fine. So if you have an ar10 lpk already, use it, but you'll probably have to get a standard ar15 bolt catch to replace the ar10 one. They're around $5

I read that big Ma Ten thread on arfcom before Christmas so, maybe I just glazed over the differences in the bolt since I knew I wanted a Noveske barrel and the differences were unimportant to me knowing I would be limited to the armalite bolt.

I also installed this receiver extension with an H3 buffer (which Vltor suggests, and they call it an AR10 buffer but its really just an H3) and an AR10 buffer spring and then put a Magpul MOE stock on it and put a Larue RISR on top of that. I originally had a PRS installed but that thing was damn heavy. The lower alone was over 5lbs with no magazine. If you do go PRS, use the H3 buffer still and the same spring. The bolt is longer than the ar15 bolt so you have to give up buffer length to accommodate for that in the rifle length extension.

Going the route of the Vltor receiver extension is much cheaper than buying a standard ar15 receiver extension and putting the Slash buffer into the gun. $100 for a buffer is unbelievably high IMO. You wont be able to collapse the stock completely using the Vltor extension because its about an inch longer. But...why would you? Who shoots with the stock completely collapsed anyway? lol Especially if you're going for a precision gun

I also got the Troy BattleRail TRX-308 12". I was astonished by its weight...or lack there of. Just make sure you measure your receiver so you get the right one. I had the older model and it was for a MA ten I got right after Christmas, so, not real sure how new the new models are

These are my observations and experience with these parts. If someone with more info wants to step in to correct me, it won't hurt my feelings. It sucks that there isn't a standard for the ar308 world and that we as the consumer have to muddle through trial and error to get a working gun.

 

[caelumatra]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Angry_Pirate</div><div class="ubbcode-body">762sass had a bunch of ar10 parts when I was deciding whether to go ar10 or dpms-format.

762SASS </div></div>

Those are good prices on those bolt parts. I've added them to my favorites if DSG or Rainier go out of stock and I need something. Thanks for the link

And here is the arfcom link to the mega ma ten build if you need it OP
http://www.ar15.com/forums/topic.html?b=3&f=121&t=516132
And here is Rainier talking about the bolt catch
http://www.ar15.com/forums/topic.html?b=3&f=121&t=517454
Heed his word over mine IMO

 

[Hellbender]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

If someone is building your barrel, you need the bolt to match the barrel extension they use. Find out, because Armalite and DPMS ARE different, I have had both in hand at the same time and measured.

 

[caelumatra]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

This is an email response from GAP when I inquired to their prices on a Rock barrel in 18" threaded to accept a BABC compensator if the OP is curious

Me:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I'm interested in buying a .308 Rock Creek barrel from you all for an AR platform. What are the prices for this with the barrel extension installed?
And do you sell compatible bolts for that barrel.</div></div>

Ken from GAP:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">AR10 barrels <span style="font-weight: bold">with extension</span> are 625.00. We request customers provide bolt for headspace.</div></div>

Me:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Is there any additional charge for cutting it to 18" and threading it for a compensator? And at what length is the gas port drilled </div></div>

Ken from GAP:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Threading is 155.00 which includes a thread protector. Mid length gas port.</div></div>

That was too rich for my blood, so I went with Noveske. I asked if they sold bolts too because I wanted a better brand than Armalite for my bolt.

 

[lolnorcal]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Caelumatra - very informative post, and thanks for sharing all that info! I've learned that Armalite AR-10 BCG's aren't hard to find at all. About the bolt differences- it was either in the big Ma-Ten thread on arfcom or a calguns thread, but I'll try to find it and post it here. From what I remember, functionality is the same but it was more of a durability aspect. I'll be using a PRS stock, and was going to go with a standard AR10 rifle length buffer tube/buffer/spring. The combination was actually one of the things I was unsure of. Is the AR10 rifle length extension the same length as an AR15 rifle length extension? I've always assumed so, since I see A2 stocks on both variants. And I believe that the Ma-Ten accepts the older "high profile" style TRX hand guard

Angry_Pirate - thanks a lot for the link! Seems like Armalite stuff really isn't as rare as I had previously thought.

Hellbender - the reminder is appreciated. This reason is the main cause for my predicament.

It's just hard to find a barrel maker that makes barrels with Armalite extensions. Krieger's website says 400 dollars, but I'm inclined to believe it'll be more. I plan on sending them my upper, BCG, hand guard for complete assembly (which is another fee in itself). I believe they say they provide a gas block and gas tube, but again I'm not 100% sure.

Can anybody suggest another barrel maker offering Armalite extensions? 22"-24" heavy profile, fluted, black and threaded to accept a brake.

 

[Casey Simpson]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Armalite. Why? Because their bolts are superior. Why? because their firing pin hole is the right size. Why? Because its smaller - the way it should be - so primers will not extrude into the firing pin hole.
A DPMS, or the one I had at least, firing pin hole measured .078". The right size is .065". DP might have corrected this, but if not, its a problem for some who shoot in low altitudes, high temperatures and humidity like me.
My source for this information is my experience, David Tubb, Glenn Zediker, Madesha Firearms, and GreTan Rifles.

 

[lolnorcal]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Casey Simpson - that sounds really familiar and may be what I had been referring to earlier in the thread. Good to hear some positive technical input about the Armalite bolts.

 

[branson1369]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Just built a MA-TEN with a Rock Creek 5R and its shooting 0.5 to 0.75 MOA regularly. I went DPMS style using JP bolt and MagPul Mags are a huge plus. I have a pretty good reference spreadsheet for a 308 build which includes links and specs from my build. If you want a copy just send me an e-mail [email protected]

 

[lolnorcal]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

I see that Rainier has both extensions available, with a UltraMatch 24", threaded...though not fluted nor does it have a black finish. I may settle, but I'm determined to find a source that'll make a decently priced barrel in the fashion I'd like it.

I may call Krieger at the beginning of next week to get a quote on the barrel and install.

 

[caelumatra]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Not all MA Tens are the same in regards to rail height.
http://troyind.com/manuals/DPMS_RECEIVERS_COMPARE.pdf
There are 2 different heights low and high.

You can buy Armalite barrel extensions from DSG
http://dsgarms.com/ProductInfo/ARMEA1147-1.aspx
Its out of stock, but someone probably has it in stock somewhere. Now what goes into mating the barrel extension to the barrel is beyond my small amount of gunsmithing abilities and knowledge. But, I could only assume that whoever is turning your barrel will know how to mate whatever barrel extension you choose to the barrel. The process should be the same and they can headspace it with your bolt. And I believe you can send your barrel to ADCO to get it black.
http://www.adcofirearms.com/shopservices/shop_.cfm?code=6
Yeah, $45 it looks like.

On the stock and buffer: I bought an ar10 compatible PRS a loooong time ago when they came in stock @ dsg sometime shortly after the election. I bought the receiver extension from brownells and I think it came with an ar15 rifle buffer and an ar15 spring and in my ignorance I thought it would work. I didn't start making my ma ten til much later. When I got the bolt and put everything together and had the PRS installed with the ar15 rifle buffer installed, the bolt would not go all the way back.

Looking at the picture of these 2 buffers, it would appear that the ar15 rifle buffer is longer than the ar10 buffer
ar10
http://www.rainierarms.com/?page=shop/detail&product_id=1911
ar15
http://www.rainierarms.com/?page=shop/detail&product_id=2630

On the good side though, the ar10 rifle buffer is pretty damn cheap.

 

[Jumper]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: lolnorcal</div><div class="ubbcode-body">I see that Rainier has both extensions available, with a UltraMatch 24", threaded...though not fluted nor does it have a black finish. I may settle, but I'm determined to find a source that'll make a decently priced barrel in the fashion I'd like it.

I may call Krieger at the beginning of next week to get a quote on the barrel and install. </div></div>
Lilja offers an AR10 barrel. I think they use a DPMS extension though. You could use a JP bolt instead of DPMS. http://www.riflebarrels.com/products/ar_10.htm

 

[lolnorcal]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

I was under the impression that all the Ma-Ten receiver sets were the older "high profile" style. I dug through the arfcom thread and saw it mentioned a few times, though I didn't do any actual physical comparison aside from eyeballing. I'll have to look into this more.

The barrel builder will likely be providing the Armalite extension, though parkerizing is another story. I'd rather have everything done in house than buy a barrel and send it out for fluting/threading/parkerizing. Luckily, Krieger offers all these services, though I can't say it sounds cheap.

Good info on the buffer. I wouldn't have really known otherwise, so I'll be sure to get an AR10 specific buffer.

Really helpful with the links and explanations, BTW. It's appreciated!

 

[jdel]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

If you have any questions on the rail height call Mega, they are super helpful and knowledgable. Raineer Arms has their own rails made by Sampson that are supposed to match up to the receiver. Whoever does your barrel can go with any extention. Check out White Oak Precision ( I beleive that's the one ) They can make any barrel you want how you want. I'm going with a Brux on mine with a DPMS extention.

 

[lolnorcal]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Looks like White Oak Precision has Krieger match barrels (or their blanks?) that they turn in house. I'll have to look into this further.

 

[branson1369]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

If you cannot get krieger in your time frame (I had that issue for my build) the Rock 5R is outstanding. I bought blanks and had them chambered, contoured, [ported and matched to a JP enhanced bolt for a decent price and great timeframe. I have been able to get 0.5 to 0.75 MOA groups from my bipod on the new build which is one of the above referenced barrelks in 18.5".

The Slash Heavy Buffer ius also an excellent choice for the build combined with a Vlltor rx extension

 

[BCP]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: lolnorcal</div><div class="ubbcode-body">Casey Simpson - that sounds really familiar and may be what I had been referring to earlier in the thread. Good to hear some positive technical input about the Armalite bolts. </div></div>

I live in Cali too(depending on where you are in Norcal we probably shoot at the same ranges) and my rifle has a DPMS bolt and DPMS barrel. About 1700 rounds now and never had a problem with the bolt, ever. If it really worries you then go with a JP bolt and a DPMS carrier + DPMS gas key.

As far as barrel make and weight, I'd say any one of the decent names out there in a 20" will do you just fine. On a budget of ~500 I would get a Hart (I have a couple rifles with hart barrels and they are incredible) or a Lilja (they have a 455$ drop in barrel in a profile I really like).

edit: if you're in the Sacramento area I can recommend a gunsmith to turn/chamber your barrel.

 

[Vindex]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Casey Simpson</div><div class="ubbcode-body">Armalite. Why? Because their bolts are superior. Why? because their firing pin hole is the right size. Why? Because its smaller - the way it should be - so primers will not extrude into the firing pin hole.
A DPMS, or the one I had at least, firing pin hole measured .078". The right size is .065". DP might have corrected this, but if not, its a problem for some who shoot in low altitudes, high temperatures and humidity like me.
My source for this information is my experience, David Tubb, Glenn Zediker, Madesha Firearms, and GreTan Rifles. </div></div>

That was my biggest issue in going with a DPMS style carrier. I held my breath hoping that one day.....

DPMS makes some pretty good product. But, it can be hit or miss in terms of quality control.

Looks like the clouds may be parting. SI Defense is about 3 months away from shipping their BCG's (a tad high, but they look good). And then there's Young Manufacturing.

I spoke with them last week, and yes, the rumors are true. Not on their website yet, but they are about a week away from hard chromed match carriers for the DMPS style 308 AR. Bolts about 3 months away.

Price for the carrier alone quoted to me is about $190.

 

[Hawk45]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Whatever you do.. do it the right way and the way you want it the first time. If you have to spend a little more, do it and be happy. Otherwise you are going to spend twice as much down the road to re-do what you wanted in the first place.

 

[msalm]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Here's a question for those that have been there, can an Armalite bolt and barrel extension, and BCG for that matter be used on the DPMS receiver platform?

 

[BCP]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: msalm</div><div class="ubbcode-body">Here's a question for those that have been there, can an Armalite bolt and barrel extension, and BCG for that matter be used on the DPMS receiver platform? </div></div>

I think the Armalite barrel uses a different barrel nut.

 

[msalm]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Yeah, I get that part, but would I be able to use an Armalite barrel extension with an armalite bolt and carrier in a DPMS style receiver with the DPMS forend? Reason I ask is the Armalite bolt is supposed to be 'better', and a have a few of those on hand, but the DPMS style uppers/lowers are more popular.

 

[lolnorcal]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hawk45</div><div class="ubbcode-body">Whatever you do.. do it the right way and the way you want it the first time. If you have to spend a little more, do it and be happy. Otherwise you are going to spend twice as much down the road to re-do what you wanted in the first place. </div></div>

Buy once, cry once...I've heard it many times on the forums, but I tend to agree. I intend on only building this rifle once.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: msalm</div><div class="ubbcode-body">Yeah, I get that part, but would I be able to use an Armalite barrel extension with an armalite bolt and carrier in a DPMS style receiver with the DPMS forend? Reason I ask is the Armalite bolt is supposed to be 'better', and a have a few of those on hand, but the DPMS style uppers/lowers are more popular. </div></div>

I know that my particular receiver set (Mega MA-TEN) uses a DPMS style nut, and I've ordered a DPMS style hand guard accordingly. I may have jumped the gun here a bit by purchasing an Armalite BCG, which will require an Armalite extension/barrel. The DPMS and Armalite threads are different and are non interchangeable, from what I read. Though, that's only a matter of the threads on the upper itself.

I'll be jumping into the MA-TEN "big thread" on arfcom and I'll report back with findings. I do know for a fact that there are MA-TENs in existence that have AR-10 BCG's and barrels, so there's hope yet. Exactly how this had been accomplished, I'm not sure.

Edit: Update. A quote from a user on arfcom, and he appears to be right.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">you must use a dpms threaded barrel nut. You can use an armalite barrel, and put a dpms nut on it, those two parts will work together just fine. </div></div>

 

[lolnorcal]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Another thought I was juggling in my mind is barrel length. I'll be attaching a JP brake at the end of the barrel, and it'll add about an inch or so to the barrel length. Makes me wonder if I should go with my original 24", or step it down to 22" and lose a bit of velocity.

 

[Redmanss]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Found a thread from a year ago that might help you out a little bit on the barrel issue:
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1816768

 

[Mute]

Re: .308 AR Platform - DPMS vs. Armalite regarding BCG

Don't worry about the BCG and the receiver threads for your handguard/rail. With the MA-Ten, you can use either a DPMS or Armalite BCG and the appropriate barrel extension. However, the handguard/rail system you choose has to be compatible with a DPMS nut. The barrel extension has no effect on this.

Regarding the receiver extension, spring and buffer, if you're going with a Magpul PRS, make sure to get the one that's designed for the AR10. It's compatible with an A2 receiver extension (which is what you'll need). You'll also need to get an AR10 buffer and buffer spring. This is the combination I used for my MA-Ten with the PRS stock.