Interesting that everyone didn't just copy whatever the standard design of the first one was.  I'm guessing everyone thinks they are improving the design, with their flavor.  So what's the story - are some large frame/AR10 lowers "Better" than others?  And how so?

It was because of the Clinton Assault Weapons Ban.

KAC made the SR25 while working with Eugene Stoner before the Federal AWB of 1994.

Eagle Arms used the SR25 upper receiver group when developing their answer to the SR25 in 1996, but couldn't manufacture new magazines that could take higher than 10rd capacity, so they made their new EA-10 rifle take modified M14 mags, and built the lower around that.  They then acquired the ArmaLite name from Elisco Tool & Machine from the Philippines (another story as to how they got it from the US Fairchild Aerospace company), and introduced the ArmaLite Inc. AR10B in 1996.  By using M14 mags, people could buy surplus GI mags and still have 20rd capacity in a ban-era rifle without having to source magazines made after the ban.

DPMS later developed the LR-308 with SR25 magazine compatibility, but it was first introduced with a polymer translucent magazine in 2003-2004 timeframe.

The ban expired in summer of 2004 IIRC, so that opened up the legality of manufacturing new standard capacity magazines.

Instead of standardizing on one magazine (SR25 like the military was already using), we saw other companies that has spent years developing other .308 rifles on surplus magazine compatibility like with the FAL (Bushmaster BAR-10-really a Rock River design later re-introduced as the LAR-8) and even G3 mags (CMMG).

DPMS also threw any chances of a standardized receiver set profile off the rails by using a curved receiver seam cut like an AR15, as opposed to the SR25 double angle cut like the original AR10s from Fairchild-ArmaLite.  Since the DPMS rifles were the most affordable, they sold like crack and became the most prolific in the market.

Read this thread for more history on the AR10, SR25, and variations

Since there's not a single military specification, I'm kind of thankful that there's as much compatibility as there is.  That said, I had to do a bunch of research before I bough the components of my .308 AR to make sure they would play nice together.

I don't know what's best.  The one I have (an AR-10 that uses the modified M14 magazines) isn't very popular.  My next .308 will either be a SCAR 17S or one of the new "small frame" .308 ARs.  I'm waiting to see how that niche develops.

Wow that was a really good reply.  Thank you sir.

Interesting...

Do tell!

History tends to repeat....

Which is what im betting on, though the Savage brings arguably more value with the slightly higher cost.  But then again, the masses tend towards low cost, and DPMS GII has a few years on Savage, as we can see DPMS GII making inroads among 3-gunners and hunters.

Personally, I LOVE my DPMS GII and there are more and more barrel and hanguard options popping up, and it already takes a host of AR15 options.  Only real thing lacking is a non-custom 6.5CM bolt and barrel.

IDK about best design, but I know the 'best' always takes SR25 pattern mags


I do wish the mil would hurry up and switch over so they will become milspec

if you have not seen these sites they have some great info and I used them when getting parts for my first AR10 build.

 https://308ar.com/compatibility/

 https://308ar.com/