.308 ARs

[lester_]

I’ve built a bunch of 5.56 rifles but I’ve never tackled a .308 AR. I thought it would be a similar process… but as I began to read up on it, I realized that the .308 is a lot different. I want to know which lowers match with which uppers before I jump into buying parts.

 

[Lhee_Vogue]

.308 ARs can be a bit strange. The main thing to know is that there are two patterns, the DPMS and Armalite and they definitely don’t get along. The uppers and lowers might look somewhat similar but the magwells are different sizes, and the pins are in different places. DPMS is way more popular right now. Armalite parts are out there but theyre a bit hard to find. Ill just stick with DPMS if I were you. Once you choose a pattern, it’s not too hard but keep in mind that everything is a bit bulkier than AR15 components. Bigger BCG, sturdier buffer, all that stuff. You can’t just grab random parts and expect them to fit like you can with a 5.56 build. If this is your first time, I’d recommend getting a matched upper and lower set from the same brand to ensure a good fit. You can always mix brands later once you get the hang of it.

 

[Alan]

There are two main patterns: DPMS .308 (most common, like Aero M5, PSA) and Armalite AR-10. Stick within one system since parts, barrels and uppers are not cross compatible.

 

[A-300 Dave]

Interesting - One is never too old to learn!! Now I know that I own a LR-308 & a AR9. Before this thread I thought I owned a AR10. I've never built one so I've never really thought there was a difference. If I understand correctly this difference doesn't exist with the AR-15's?? Thanks for the education - I'll be following along.

 

[Fodderwing]

I bought a 308 from Palmetto State Armory 10 or so years ago. The PSA AR10 ses the Pmag magazines and is a DPMS clone.

Trigger, safety, bolt release, other small parts are AR15 compatible.

 

[Shooter308]

I run mostly Bolt Action 308's. Do have one Semi-Auto M1A Scout which I used to run in Three Gun in Heavy Metal Division with 25 round Magazines and with a 4 X12 Power Scope but 7.62 X 51 surplus was a lot cheaper then.

 

[ga41]

Even though I don’t currently own a 308 version, glad I read this , learn something new every day even after 68 years
Thanks !

 

[Ragnarok]

.308 lowers and uppers don’t always play nice like the 5.56 builds do. The DPMS pattern is common, but you really have to double-check before buying.