1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Super cross between AK-47 and AR15: SR-47

Discussion in 'Rifle Country' started by Forseti, Apr 3, 2003.

  1. Forseti

    Forseti Well-Known Member

    This has been posted before, but MAN is it neat, and thought it deserved is own thread.

    It is listed at http://www.quarterbore.com/kac/sr47.html

    Knights Armaments page is at:

    I plan to contact them, and ask for a civilian version...it would be very neat...

    US special operations forces have received a small number of new assault rifles optimised for the type of cave-complex fighting experienced in Afghanistan.

    The weapons are based on the M-4/M-4A1 carbine variants of the M-16 assault rifle family, but fire the 7.62 x 39mm Soviet-designed cartridge and magazines used in the AK-47 assault rifle.

    Knight's Armament Company of Vero Beach, Florida, delivered the first six rifles, called the SR-47 (Stoner Rifle-47), to the US Special Operations Command (USSOCOM) in January. The company received a contract for an initial six weapons in late October 2001.

    David Lutz, vice president of military marketing for Knight's Armament Company, said: "For the last couple of years there was a requirement in USSOCOM for an addition to their [M-4 series carbine] SOPMOD [Special Operations Peculiar Modification] kit that they called a 'Special Purpose Receiver' (SPR).

    "Originally they called it the SPR V1 for 'variant one', and it was to be a drop-in 7.62 x 39mm receiver replacement."

    According to Lutz, government laboratory efforts to satisfy the SPR requirement were further complicated by "user input" from the USSOCOM specifying that special forces did not want to use the "straight box" M-16 magazines but instead wanted to utilize "battlefield pick-up" AK-47 magazines taken from opponents.

    "That was a dilemma because the AK-47 magazine won't go well in a straight chute dimensional magazine - it just won't happen," he said.

    He added: "But actually this program was kind of on a back-burner until US special operations guys were going into these complex of tunnels that were so deep, expansive and target-rich that they couldn't take enough loaded M-16 magazines. So they wanted a weapon that had all the muscle memory of an M-4 - safety, grip, everything that's familiar to the soldier or the SEAL - but capable of using battlefield pick-up magazines."

    Instead of a drop-in receiver addition to the SOPMOD kit, design changes mandated a completely new weapon with resulting change in terminology from Special-Purpose Receiver to Special-Purpose Rifle (SPR).

    "To enable the use of battlefield pick-up magazines, we had to make the upper and lower receiver 0.25in longer. You couldn't take an M-4 receiver and even machine it out to take the AK-47 magazine because it was too short. That also meant that the bolt carrier had to be made longer and the firing pin had to be made longer.

    "So you started losing what some people would have liked to have in terms of optimal interchangeability of parts; that's just part of the trade-off to fire the different cartridges," Lutz said.

    He highlighted the advantages of the 7.62mm size round for close-quarter battle (CQB) operations. Noting that many of the world's counter-terrorist organizations have evolved from 9mm to 5.56mm ammunition over the last decade, he highlighted the larger 7.62mm ammunition for the ability to package heavier, slower bullets that could provide greater contributions in CQB scenarios.

    In addition to the extended upper and lower receivers, another challenging design effort in the SR-47 involved getting the M-4/M-16 magazine catch to externally function like the M-16 magazine but work with a curved AK-47 magazine. In practice, US soldiers use gravity to 'drop' their empty M-16 magazines. The SR-47 design requires the introduction of an internal magazine ejector to push the empty AK-47 magazine from the bottom of the weapon. Additional design features include the introduction of a free-floated match grade barrel.

    "This particular 7.62 x 39mm is probably the most accurate 7.62 x 39mm in the world because it's got a really fine free-floated barrel," Lutz added.

    "And, of course, it has the rail system so all of the other SOPMOD accessories off the M-4s are compatible.

    "There's also a possibility, although they haven't let the contract yet, that there could be another variant that we'd call the SR-74. That could be used if our special operations guys go to a country that has the 'newer' 5.45mm former Soviet weapons. Then they would also have the same ability to pick up magazines."

    All six of the SR-47s were delivered with sound suppressors, which Lutz described as "essential" in tunnel operations because of the weapon report.

    "We don't know how the six did," he said. "We don't know if they are ever going to order one more. We don't know if we're going to get the second phase, which is to develop the 5.45mm version. But this is probably the hottest weapon that's out there right now."

    Lutz concluded: "The SR-47 is a great gun because of the three technologies that it marries: the basic Stoner gun design; the AK-47 series cartridge and magazine; and the modular weapon concept."

  2. Nightcrawler

    Nightcrawler Well-Known Member

    A 7.62x39mm AR is nothing new, but the ability to take AK magazines is something.

    Hmm, who would've thought? The next big thing in the elite, tactical, close-quarters-battle arena: the '40s vintage 7.62x39mm round! LOL

    I also like Robinson's entry into this arena:

  3. BusMaster007

    BusMaster007 Well-Known Member

    The M16 with an AK47 mag looks positively RAKISH, doesn't it?
    :evil: I LIKE IT.
  4. Badger Arms

    Badger Arms Well-Known Member

    They made it 1/4" longer... both the upper and the lower. Then they made a longer carrier and firing pin? Why??? Why didn't they just cut further back into the trigger-guard area? You don't need the bolt hold-open device in that situation.

    Yes, I want one. However, the whole premise for using this is wrong. Why not teach the grunts to shoot AK's? Much cheaper. I'd be interested to see if they can make an AK-74 that uses a simple bolt or maybe even an extractor change if that is even needed. The lower, of course, would have to be different but the upper could be made in .223 to take the tougher, more reliable, fully-curved AK-74 magazine. Kewl. I want one.
  5. MiniZ

    MiniZ Well-Known Member

    Its cool, it would be fun to have, but I wouldn't hold my breath on Reed Knight offering it to the public. If he does, it will be a very pricey limited run-kind of like his ARs.

    I don't know if Robinson's entry has hit the market, but saying it has, there is at least hope you can actually get one.
  6. modifiedbrowning

    modifiedbrowning Well-Known Member

    According to Robinson's website their Rav02 rifle is select-fire military only. Not even cops can buy them at this time.edited to change enough to even.
  7. Bostonterrier97

    Bostonterrier97 Well-Known Member

    It doesn't seem that great to me..if they were going to go to that much trouble with a new rifle, Knight's Armament might as well as replaced the direct impingment Gas System of the AR with an AK/Daewoo style Gas System, and they might as well have reduced the number of locking lugs on the bolt to 3. These modifications would have enhanced reliability.
  8. Correia

    Correia Moderator Emeritus

    Worst of both worlds. :)

    Now a .223 AK, now we are talking.
  9. Handy

    Handy Guest

    Have to go with Correia on this one.

    The heavy, inaccurate ammo of an AK coupled with the AR bolt system?

    Oh, goody. It's like using what they had left over after making the Galil or Daewoo K2.

    It might be neat if it was cheap, but this is a Knight product, so it will cost $2K.
  10. Bainx

    Bainx member

    Looks like it didn't know what it wanted to be.
  11. Forseti

    Forseti Well-Known Member

    Ok, I forgot something....the gas system of the AR...goodness knows what Russian powder would do to it in terms of fouling. Maybe nothing, maybe it becomes a jam-o-matic. Would be interesting to know...

    I imagine the accuracy WOULD be excellent, since the barrel is free floating, and the gas system means you don't have a mass (the gas piston) sliding back and forth with every round.

Share This Page