AR-Type .308 Questions

[Polar Express]

So I bought and built my M1A, (thanks for the tips, H2OMAN), and I'm super happy with it.

But, now it's time to start to think about the 'next' gun....

I think I would like to build an AR-type in .308. While thumbing through the brownells catalog in the 'library', I have noticed that you can purchase lowers to build your own rifle with.

Something that has caught my interest, is that there are different lowers made to accept different .308 mags.

To me, this brings up lots of questions, and I'd be grateful if some of you with more knowledge than I have would be kind enough to share what you know and think.

So far, I have seen two kinds: "DPMS" style and "G3" style. If there are more styles than that, what are they? What are the pros/cons of each?

So far, it appears that the G3 mags are much less $$, but do they work as good, or worse, or better? The note with the product says some minor modification will be req'd to the upper assy to use the G3 mags, but will that preclude that upper from working in a different (say DPMS) lower with proper mag?

With this build I don't think I want to go super "tacticool" with it, but rather focus on a rifle that can be used for a variety of uses, even so far as having multiple uppers that swap out to make those changes. That would be more 'down the road', but I want to at least consider those details with this plan.

The other thing, is that I may not know what questions to ask, so if you feel I have not asked something that should be discussed, please let me know.

Thanks,
PE

 

[Quiet]

Generally there are five different 7.62x51mm/.308Win AR type lower recievers.

1. Uses Armalite AR10 magazines.
2. Uses DPMS LR308 / KAC SR25 magazines.
3. Uses H&K HK417 magazines.
4. Uses FN (metric) FAL magazines.
5. Uses H&K G3 magazines.

More manufactures seem to have gone with the DPMS/KAC magazines.
Magpul now makes DPMS/KAC magazines.

The AR lower that uses G3 magazines, also needs a upper that has been modified to use G3 magazines. Due to the dimensions of the G3 magazine, the internal dimensions of upper reciever needs to be wider than the Armalite & DPMS upper recievers. Also due to the nature of the G3 magazine, there is no bolt hold open feature. In addition, the G3 magazine's feed lips need to be modified to provide reliable feeding.



IMO...
If I was to get a 7.62x51mm/.308Win AR platform, it would be the LMT MWS-308 (which uses the DPMS/KAC magazines).

 

[madcratebuilder]

So far, I have seen two kinds: "DPMS" style and "G3" style. If there are more styles than that, what are they? What are the pros/cons of each?

ArmaLite and Noveske, both use the modified M14 mag. The M14 mag because ArmaLite developed the current AR10 back in the ban era and the M14 mag offered existing high capacity mags. The current ArmaLite GenII have a high MSRP but are almost always on sale for about $25. I've managed to pick up over a dozen GenII's in new/used condition for under $20 each. If you have to run PMAGS go with DPMS.

Any of the many styles can be tack drivers with a good barrel. The 7.62 platform rifles do not share parts like a AR15. Barrels, barrel nuts, hand guards, uppers and lowers, do not interchange between manufacturers.

One reason I chose to go with ArmaLite is ArmaLite re-engineered the bolt stop and mag catch for the AR10. Other manufacturers use the AR15 parts that may have function issues.

I ended up with a ArmaLite lower and a Noveske upper. My only complaint is weight.

 

[Polar Express]

Thank you both very much for your answers!

Any other suggestions or thoughts for someone looking to 'build' one of these?

PE

 

[henschman]

I like the idea of using a MA-Ten receiver set from Mega Arms. This is a matched lower and upper. The lower takes KAC/DPMS mags, which is a good choice because you can use the cheap, durable P-mags in them. The upper is designed to accept the barrel and bolt carrier group from either a KAC/DPMS pattern, or an Armalite pattern, which gives you a lot of options. For all the rest of the parts, you just use regular AR-15 parts, which means that parts are easy and cheap to find.

I am planning a build with a MA-Ten. I want to use an Armalite AR-10 barrel because they are the only ones I know of who make a 20", chrome-lined, light-profile barrel for a .308 AR -- I am trying to keep the rifle light -- but I want DPMS pattern mags so I can use P-mags.

I don't like the idea of a lower receiver designed to take G-3 mags... it seems like it isn't worth all the compromises and modifications necessary to make it work, just to save a few bucks on mags.