Author Topic: SR-25 vs AR-10 mags  (Read 10215 times)

Offline jj32

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SR-25 vs AR-10 mags
« on: December 01, 2008, 08:25:31 PM »
What is the difference between the SR-25, POF, DPMS mags and the AR-10 mags? 

IIRC, the magwells of these other rifles are perpendicular to the deck.  If this is the case, can an SR-25 mag be converted for use in an AR-10?  Or can Justin's AR-10 lower be milled vertically to accept an SR-25 mag?

Offline ScottRS

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Re: SR-25 vs AR-10 mags
« Reply #1 on: December 23, 2008, 09:23:23 PM »
I believe an otherwise Armalite-compatible lower could be machined square to the deck to accomodate a DPMS/SR25 mag, but because the mag walls and feed lips are a fixed (within that mag) relationship, once you have a lower for one mag configuration or the other, you can't swap back and forth--you have to use the mags that that lower is machined for.

Swapping back and forth across the Armalite/everyone-else gap would net you rounds that either point up or point down (depending on the direction you swap) and probably won't feed properly either way.

Offline jj32

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Re: SR-25 vs AR-10 mags
« Reply #2 on: January 09, 2009, 12:10:09 AM »
I don't have any of the newer SR-25 style mags in hand to measure against an M-14 mag so I can't tell for sure if the AR-10 magwell will accomodate the new style mags.

Pros and Cons
SR-25 mags:  C-products has good pricing on the new style Stainless .308 mags ($22).  They are not in the demand that M-14 mags will be before AWB v2.0.  The only problem is that the SR-25 mag may not hold open the AR-10 bolt.

M-14 mags:  Armalite/CMI manufactured mags are pricey ($45) and true M-14 mags, while plentiful and of varied quality, must be converted with a milled slot.  M-14 mags cannot be switched back and forth between the AR-10 and M-14 due to different followers (if you want the bolt hold open feature).  On the upside, I believe the new Beta mag can be adapted to the AR-10.

Does anyone have an SR-25/DPMS/POF lower or blueprint to compare against the AR-10 magwell specs to determine if the new mag will hold open the bolt?

Offline ScottRS

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Re: SR-25 vs AR-10 mags
« Reply #3 on: January 14, 2009, 10:24:55 PM »
A friend brought by a couple of mags that I'd not handled before, today.  I learned a fair bit in the process.

The current DPMS mag has a narrower, but with a larger standoff, rear rib, than the current Armalite mag.

The current DPMS mag is also more square than the current Armalite mag, and is of very similar overall dimensions to a G3 mag.

I believe the mag catch height to be compatible.

I believe that the DPMS bolt catch would work in an Armalite lower; I'm not sure about the other way around.

Bottom line: You can't put an Armalite mag into a DPMS lower because the rib is too wide at the back, and I believe the main mag is also a little too long.
You can't put a DPMS mag in an Armalite lower because it's too wide throughout, particularly at the front, because the Armalite lower is cut for the tapered Armalite mag.

I still believe that you *could* cut an Armalite style lower to accept DPMS/SR25 mags.  However, today's attempts at interchange suggest that an attempt at a jack of all (AKA a magwell opened up to allow for either to work) would probably be proverbially master of none, and would have to have the mag-locating features opened up so loose that both mags would slop around and probably have trouble.

On the assumption that DPMS mags are entirely compatible with SR25's, I would assume that the same would be true of the SR25 mags.  Unfortunately for me, I don't know anybody who actually has one of those.

Offline jj32

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Re: SR-25 vs AR-10 mags
« Reply #4 on: February 06, 2009, 09:16:17 PM »
I spoke to C-Products about their .308 mag.  I works in the SR-25, POF, and DPMS rifles.  The buffer tower end of the SR-25 receiver has the same angular structure as the AR-10 but the magwell end is probably slightly longer to accomodate a magazine with no cant (perpendicular to the deck).

Offline limeytwo

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Re: SR-25 vs AR-10 mags
« Reply #5 on: March 20, 2009, 06:44:51 AM »
I have both an Armalite AR10 and an SR25 the uppers are basically the same other than the pins on the SR25 are fractionally larger, .281 vs .275 I think, I think that any one that could/would produce a lower that copies the SR25/Late AR10 format that uses the SR25/DPMS style mags woulds be onto a winner as many people like the AR10 uppers but would like to use the fast becoming standard SR25/DPMS magazines, the only problem I would see is most people don't have the capability to finish a 10 or may be even a 80% receiver,
as far as the other parts, I have used standard AR15/DPMS 308 (same part) mag catches in my Armalite, I have also used DPMS 308 bolt stops in a AR10 so a lot of the parts interchange, so if you could just adjust the magazine well in an Armalite programmed lower to use the DMPS style mag everything else could be worked out.

Offline trwalsh

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Re: SR-25 vs AR-10 mags
« Reply #6 on: August 27, 2009, 09:06:31 PM »
... so if you could just adjust the magazine well in an Armalite programmed lower to use the DMPS style mag everything else could be worked out.

I know this is an old thread, but I was wondering who can perform this service? I have one of Justin's AR-10 billet lowers that Mitch finished to completion before he turned into an ass. But I haven't done anything with it yet. It's still not even anodized.

I have long wished that it would use SR-25 mags since, I agree, that style is fast becoming the standard pattern. I would love to put a complete Noveske AR-10 style upper on it, but be able to use SR-25 mags. Can anyone re-machine my magwell for me?
Yes, I'd like an M240 please...no no, the other one, the belt fed!  Oh, and while I'm here, let me also get a big gulp, a powerball quick-pick, and a pack of Marlboro's, Thanks.