SR-25 Vs AR-10 - New Rifle Build

Discussion in 'Rifle & Shotgun Discussion' started by AMProducts, Aug 7, 2010.

  1. AMProducts

    AMProducts Well-Known Member

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    So I'm thinking about taking the plunge and building a .308 AR platform.

    I have done quite a bit of reading, but there doesn't seem to be a lot of definitive information out there, and I'm guessing some of you gentlemen might be able to put this in perspective.

    I have decided on the SR-25, my understanding is this design while similar to the AR-10 requires a different reciever, barrel, bolt group and trigger. Also, magpul started making magazines for this gun, which means they are availible for $20, not the $50 for AR-10 mags (if you can find them).

    To my understanding, the SR-25 is referred to as either the M110, or the "DPMS pattern". At this point I know the following vendors make guns like this.

    Noveske
    Kaiser Defense
    JD Machine Tech

    Other magazine patterns
    Rock River Arms (FAL mags)
    unkown (HK91 mags)
    POF (POF mags? Claims to take DPMS mags)

    Other info: C-Products sells a magazine which claims to fit: DPMS, POF, LMT, LWRC, Sabre Defence, SR25

    So my questions...

    Right now I'm leaning towards the JD Machine, as it's the lowest price I've encountered at about $350. I have considered just dumping the money on a DPMS panther, but I've only been marginally happy with the DPMS uppers I've bought in the past (Straight pins under the FSB?! WTF!!)

    Just to double check, which parts kits do they require? I have yet to see anyone offer an SR25 or AR-10 parts kit to outfit the lower.

    Does the rifle use standard stocks? It seems most do... and do they use a standard barrel nut? If the gun uses standard stocks, I would conclude the BCG is longer, but of similar diameter to a standard .223 BCG.

    If the barrel nut is the same size, is the FSB similar? .750" is standard .223 barrel diameter at that point, which is plenty enough for a .308. This means I can use standard free-float tubes and the like.

    If any of you have gone through the process of building one, and have any suggestions, by all means share!
  2. NoAim

    NoAim Member

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    FYI, AR-10 mags are $30 each and currently in stock: AR-10 5 Pack Magazine Special

    You are also mistaken about Noveske. Those are AR-10 pattern rifles.

    Additionally, the SR-25, DPMS, POF, LaRue, LMT can all use the DPMS pattern mags. But the shape of the upper and lower receivers are different so you must use a matched set.

    There is a lot of parts commonality, but some things are different.

    As for parts kits, you will need to purchase a parts kit that matches your rifle.
    AR-10 ones here: LOWER PARTS KITS
    The others can be found.

    The rifles can use standard stocks, but you need to match the buffer to the buffer tube. As an example, you can't use a standard AR-15 buffer and a standard AR-15 rifle length buffer tube. Since the .308 bolt carrier is about an inch longer, if won't be able to retract all the way. You can use a shorter buffer, or a longer tube to match. Which you use depends on what you want to do and what's available.
  3. BillCh

    BillCh Member

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    What about something like an M39 with a 22 barrel?

    If you've already decided then this wouldn't interest you.
    My latest. Mk 14 Mod 1

    Sounds like you have fun times ahead regardless of which way you go.

    B

    [​IMG]
  4. AMProducts

    AMProducts Well-Known Member

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    I already have an M1A, and love it the way it is, in the classic wood stock, with the standard long barrel. I find I tend to shoot my bolt gun more often, or one of the many AR's I've already built. I think the interest here is simply to do something I havn't done yet.

    As far as what I've decided... I'm going to call JD machine on monday and ask them about it. I may just send my FFL down there and see what pricing is like. All this obama/california premium on black rifle stuff gets old.
  5. locobob

    locobob Well-Known Member

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    The SR 25 is made by Knights Armament Corp and has been adopted by the U.S. Military as the Mk11 (Navy, Marines) and the M110 (Army). Mags are now available from Knights, Magpul, Larue Tactical and one or two other sources.
    Because of their military contracts I would lean toward guns compatible with the SR-25 platform over the Armalite pattern. That said I don't see a big problem with AR-10 parts availability, they seem to have a pretty good following. I have some used SR-25M parts I'm looking to sell that could help you keep costs down: 24' barrel, gas block, CF handguard, 30mm scope rings - all genuine KAC parts. Let me know if you are interested.
  6. NoAim

    NoAim Member

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    FYI, AR-10 and LMT also have military contracts.

    Note that the "compatibility" between platforms is very strange. Lots of them are DPMS/KAC mag compatible, but not for accessories or even upper/lower receiver fit. To be blunt, pick the platform as a "system". You really can't count on swapping parts like the AR-15 world. Knights mags, while VERY close are different than DPMS/CProducts.
  7. madcratebuilder

    madcratebuilder Well-Known Member

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    +1

    ArmaLite and Noveske make their uppers and lowers from forged 7175-T73. DPMS 's are from billet, not sure about KAC, may be both.

    The cost of mags is a none issue for me, I just bought seven Gen II mags of Gunbroker for $18.75 each, doesn't get much cheaper.

    There's a good FAQ at AR15.com on the AR10 and the other platform rifle. It covers the compatibility issues.
  8. NoAim

    NoAim Member

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    FYI, the standard DPMS upper is extruded, not billet or forged (and 3 different rail heights depending on which version and generation). KACs are forged, (I think). Iron Ridge makes a billet.
  9. madcratebuilder

    madcratebuilder Well-Known Member

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    DPMS is extruded from 6066-T6, I didn't know that:huh:. I'm not sure if I would want an extruded upper or not. All the high pressures are contained in the barrel so I guess it doesn't matter.
  10. Ryo

    Ryo Member

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    Just an FYI.
    The LMT MWS and KAC SR-25 are interchangable upper and lower as confirmed by Trey Knight. I've seen/held the LMT version and did notice they both use the same BCG and LPK as my SR-25.
  11. terrylf72

    terrylf72 Member

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    Testing is now complete on Mega’s new MA-TEN .308 receiver set!

    Mega Arms :: Latest News

    I will be getting my set.