SR-25 Magazine

[Larry Ratliff]

I just finished my LR-308 build (PA-10 lower, Gaunlet Arms "Gobiln" upper, 20 inch Gorilla Mach barrel) and headed to range to test it with my 155 gr Hornady BTHP.
I'm using 20 rnd SR-25 mags and ran into a snag. Locked bolt to the rear and Insert one 20 rnd magazine (fully loaded) hit bolt release.......wont budge.....stuck. So remove mag, release bolt, charge bolt (without mag) release bolt, function test good. Repeat load procedure, same result, bolt catch won't release bolt....stuck.

Range work around (till I can get home and properly troubleshoot) close bolt, insert fully loaded mag, charge weapon, bolt strips rnd and works fine and even locks back on last rnd. So what's the problem you ask? BCG, Bolt Release.....Magazine?
Seem bolt release is hanging up on edge of the follower guide (see pics) but works fine when Mag is inserted first then charged. So I trimmed edge of Mag allowing bolt release to move freely while Mag retains functionality and bolt still locks to the rear on the last round.

 

[msgriff]

1st rule for large frame builds: Don't mix manufacturers of uppers and lowers.
2nd rule: Use the bolt catch and pivot/takedown pins that are sold by the lower manufacturer.

 

[BCP]

Was this a complete palmetto lower or stripped and you assembled it ?

And what mags are those?

 

[strikeeagle1]

as BCP inquired, "And what mags are those?"

Is this a KAC SR-25 or a clone AR-10 ?

Looks like that magazine tab is hanging on to the follower by the skin-of-its-teeth.

 

[Larry Ratliff]

Was this a complete palmetto lower or stripped and you assembled it ?

And what mags are those?

Assembled myself, I never pay others to do what I can do myself.

as BCP inquired, "And what mags are those?"

Is this a KAC SR-25 or a clone AR-10 ?

Looks like that magazine tab is hanging on to the follower by the skin-of-its-teeth.

Those are SR-25 mags made by ASC out of New Britain Connecticut.

 

[Larry Ratliff]

Assembled myself, I never pay others to do what I can do myself.

Those are SR-25 mags made by ASC out of New Britain Connecticut.

 

[Larry Ratliff]

I have been building AR-15, AAC 300 (Rifle and Pistol), Glock clones (G19 and 17)

1st rule for large frame builds: Don't mix manufacturers of uppers and lowers.
2nd rule: Use the bolt catch and pivot/takedown pins that are sold by the lower manufacturer.

Mixed uppers and lowers is not a hard and fast rule. A mil-spec part is a mil-spec part. I bought takedown and pivot pins from Palmetto State.......and they rusted.....so I use Strike Industries Pins. But back to mixed uppers and lowers. I've built numerous AR style weapons platforms and never had an issue with BCA, Anderson, Aero, Gorilla or Durkin parts, it's all a matter of preference. You do what works for you, there is no hard and fast rule that states "never mix upper and lowers. That is the reason when the military went with the Colt M16, everything must be mil-spec and also transferred into the civilian AR-15 market. But AR-10......not so. Eugene Stoner never got a military contract for the AR-10 and the specs were sold to the Dutch, so AR-10 is kind of a misnomer, it's really a LR-308. DPMS much later started producing LR-308 parts and the rest of the weapons industry followed suit.

 

[Hound Dog]

I have a couple of those 308 ASC mags. In my LaRue or Armalite they will not work. The ASC mag jams the bolt so tight on the LaRue it won't open or close, pending on when you put the mag in. The Armalite is about the same just not as bad. The factory LaRue mag works fine in both rifles, and the P-mags work fine in both rifles. the Armalite actually came with a 20 round P-mag.

 

[DeathBeforeDismount]

I have been building AR-15, AAC 300 (Rifle and Pistol), Glock clones (G19 and 17)View attachment 8210092View attachment 8210093

Mixed uppers and lowers is not a hard and fast rule. A mil-spec part is a mil-spec part. I bought takedown and pivot pins from Palmetto State.......and they rusted.....so I use Strike Industries Pins. But back to mixed uppers and lowers. I've built numerous AR style weapons platforms and never had an issue with BCA, Anderson, Aero, Gorilla or Durkin parts, it's all a matter of preference. You do what works for you, there is no hard and fast rule that states "never mix upper and lowers. That is the reason when the military went with the Colt M16, everything must be mil-spec and also transferred into the civilian AR-15 market. But AR-10......not so. Eugene Stoner never got a military contract for the AR-10 and the specs were sold to the Dutch, so AR-10 is kind of a misnomer, it's really a LR-308. DPMS much later started producing LR-308 parts and the rest of the weapons industry followed suit.

That really doesn't mean shit. Ar15's and Glock kits are pretty much legos at the point, as the standardization has been fleshed out of the last 20 years and tens if not hundreds of millions of rifles and kits sold. Putting a functioning AR15 together just means you have an IQ above "retarded".

You are 100% wrong about large frame AR's. There is little to no standardization across different manufactures, and what little there is, you need to be knowledgeable and experienced to understand. This is a learning experience for you. You are learning the hard way because you made assumptions that were wrong.

We don't need the half ass attempt at a history lesson, when many of us have been building and fucking with small AND large frame AR's for over 20 years. You are wrong on most of your statements, so it would be wise to back away, do some more reading and research before you piss away more money.

 

[BCP]

Try some magpul 20rd 308 magazines.

Also if you are stuffing 20rds into each one try 17 or 18 maybe the magazine spring is a bit too strong.

 

[hlee]

Sounds like you don’t need any additional assistance.

 

[hlee]

That really doesn't mean shit. Ar15's and Glock kits are pretty much legos at the point, as the standardization has been fleshed out of the last 20 years and tens if not hundreds of millions of rifles and kits sold. Putting a functioning AR15 together just means you have an IQ above "retarded".

You are 100% wrong about large frame AR's. There is little to no standardization across different manufactures, and what little there is, you need to be knowledgeable and experienced to understand. This is a learning experience for you. You are learning the hard way because you made assumptions that were wrong.

We don't need the half ass attempt at a history lesson, when many of us have been building and fucking with small AND large frame AR's for over 20 years. You are wrong on most of your statements, so it would be wise to back away, do some more reading and research before you piss away more money.

Nope, he’s got this wired. No assistance needed…

 

[Larry Ratliff]

That really doesn't mean shit. Ar15's and Glock kits are pretty much legos at the point, as the standardization has been fleshed out of the last 20 years and tens if not hundreds of millions of rifles and kits sold. Putting a functioning AR15 together just means you have an IQ above "retarded".

You are 100% wrong about large frame AR's. There is little to no standardization across different manufactures, and what little there is, you need to be knowledgeable and experienced to understand. This is a learning experience for you. You are learning the hard way because you made assumptions that were wrong.

We don't need the half ass attempt at a history lesson, when many of us have been building and fucking with small AND large frame AR's for over 20 years. You are wrong on most of your statements, so it would be wise to back away, do some more reading and research before you piss away more money.

Wow.....thank you for those thoughtful words of advice, so nice of you to take time out of your busy day to expound me on your vast knowledge of weaponry.

 

[BCP]

I have a couple of those 308 ASC mags. In my LaRue or Armalite they will not work.

I've had problems with ASC mags in everything.

 

[strikeeagle1]

Welcome to the Hide. Buff it off and get back at it.

 

[mheimer_45]

That really doesn't mean shit. Ar15's and Glock kits are pretty much legos at the point, as the standardization has been fleshed out of the last 20 years and tens if not hundreds of millions of rifles and kits sold. Putting a functioning AR15 together just means you have an IQ above "retarded".

You are 100% wrong about large frame AR's. There is little to no standardization across different manufactures, and what little there is, you need to be knowledgeable and experienced to understand. This is a learning experience for you. You are learning the hard way because you made assumptions that were wrong.

We don't need the half ass attempt at a history lesson, when many of us have been building and fucking with small AND large frame AR's for over 20 years. You are wrong on most of your statements, so it would be wise to back away, do some more reading and research before you piss away more money.

He’s not wrong you know. Large frames are whole different ball game. I’ve got over a dozen large frame asc mags and they work with just fine with all my large frame rifles. (Dpms pattern).

 

[TheOE800]

Duramag, Larue, KAC. Magpul for polymer.

 

[msgriff]

The Strike Industries bolt catch in a PSA PA-10 lower is the issue. Although the PA-10 can use many DPMS LR-308 (and some AR-15) parts, their receivers are not true DPMS spec. The datum reference for AR receivers is the center of the pivot pin hole (X, Y, and Z), all measurements originate there. The PA-10 (and the "new" DPMS/Panther, which is a re-branded PA-10 since JJE bought it) use different dimensions than the legacy DPMS, most notably the dimension to the centerline of the bore. This may or may not cause function issues, and alignment between the lower receiver extension and the bore of the upper should be checked when mixing upper and lower receivers.

 

[Hound Dog]

Since we are on the subject. I had one Lancer L7 mag still in the wrapper. I took it out and run 2 boxes of Hornandy 178 eldx through the LaRue this evening. It worked fine. Not sure it is worth twice the price of a P-mag but at least it worked. More than I can say for the ASC.

 

[Cascade Hemi]

We don't need the half ass attempt at a history lesson, when many of us have been building and fucking with small AND large frame AR's for over 20 years. You are wrong on most of your statements, so it would be wise to back away, do some more reading and research before you piss away more money.

Please post a picture of an AR10 build you did 20 years ago.