SBR in 7.62x39mm Questions
Page 1 of 3 123 LastLast
Results 1 to 10 of 28

Thread: SBR in 7.62x39mm Questions

  1. #1
    Rifleman Ghost-6's Avatar
    Join Date
    Nov 2011
    Posts
    125

    SBR in 7.62x39mm Questions

    Amigos!

    I'm sorry if these questions are covered elsewhere, I hope I'm in the right folder. I have a standard XCR in 7.62x39 with a 16" heavy barrel. I'm interested in going the SBR route, but I can only afford to do this once, so I could really use some expert advice. Questions are as follows:

    1. Can anyone tell me how the XCR performs with an 11" or 12" barrel in 7.62x39? Reliability or accuracy problems? Does it beat up the gas system or the buffer/spring/op-rod?

    2. I'd like to keep the level of durability the rifle has now without modifying or drilling-out the gas ports. On a short barrel, is this an issue? Overgassing or under-gassing?

    3. I am guessing with a barrel that short the rifle becomes a flamethrower. Has anyone tried a flaming pig, 2-chamber AK-74 brake, or the 4-piece "Krink" brake? Evidently there are lots of choices but the Russian-made parts are rare, and 14/1 thread pitch. They all generate different gas pressures, not sure if that is helpful or hurtful on an XCR. Any ideas?

    4. Does the barrel profile matter on an SBR? Light vs. heavy? Fluting or not?

    Thanks in advance,

  2. #2
    Super Moderator Underground's Avatar
    Join Date
    Dec 2008
    Location
    Murfreesboro, TN
    Posts
    6,143

    Re: SBR in 7.62x39mm Questions

    I have a mini in 7.62x39, works great. Loud as hell.

    You might not want the Bulgarian/flaming pig on there, it's heavy and you shouldn't need to extra back pressure. It's an adjustable gas system, it's not going to beat anything up unless you keep the gas turned up all the time (break-in excluded).

    Check out Spikes or Battlecomp. You should be able to use any of the .308 brakes on there like so, http://www.spikestactical.com/new/z/...308-p-927.html



    That guy, he said I should be oblong and have my knees removed. But I don't trust him, he plays the banjo.

  3. #3
    XCR Guru Sean K.'s Avatar
    Join Date
    Nov 2008
    Location
    AZ
    Posts
    21,865

    Re: SBR in 7.62x39mm Questions

    On a standard length upper (Non-mini).....Alex recommends NOTHING shorter than a 12" bbl in 7.62x39 to cycle properly with all ammo. The pressure curve is lower than 5.56 so he claims you need the extra bbl past the port to run reliably.

    If you cut down to 12" you may only need the 12" gas dial.....however, you may also have to open the bbl and even the gas block ports. It's not rocket science and I've posted some port sizes in a thread somewhere here on the site.

    If you go shorter than 12"....you most likely WILL have to open ports to get it to run on any ammo. Again....the thread about port sizes will be helpful.

    Yes, a short bbl will throw flame and the only way to counter that is with something renowned for suppressing flash.....like a Smith Ent. Vortex, or Phantom, etc. That will not reduce recoil however. You're ideas of running a Pig, krink or Ak74 brake will NOT reduce flash....only recoil. What are you trying to accomplish?

    You may find more options for brakes or flash suppressors by threading standard 5/8-24 rather than metric 14x1mm LH AK....just depends what type brake/FH you are looking for.

    The recoil check (2 port) from Armlite in 5/8-24 is quite effective for $30.

    Bbl profile is totally up to you. Personally, I'd flute one if you're going to go to all the trouble and expense of turning one down....otherwise, if it were an option ......I'd get a light profile for that application.

    :2cents:
    "Necessity is the plea for every infringement of human liberty. It is the argument of tyrants; the creed of slaves."-William Pitt the Younger

  4. Remove Advertisements
    XCRForum.com
    Advertisements
     

  5. #4
    XCR Guru Sean K.'s Avatar
    Join Date
    Nov 2008
    Location
    AZ
    Posts
    21,865

    Re: SBR in 7.62x39mm Questions

    "Necessity is the plea for every infringement of human liberty. It is the argument of tyrants; the creed of slaves."-William Pitt the Younger

  6. #5
    Rifleman Ghost-6's Avatar
    Join Date
    Nov 2011
    Posts
    125

    Re: SBR in 7.62x39mm Questions

    Thanks guys!

    Do more XCR guys buy a barrel and get it turned down or just buy it short? Is there a gunsmith who cuts/flutes/crowns that anyone will recommend? The class 3 paperwork will take a looooong time so I can research smiths but I'd like to hear if anyone knows who does good work...

  7. #6
    XCR Guru Sean K.'s Avatar
    Join Date
    Nov 2008
    Location
    AZ
    Posts
    21,865

    Re: SBR in 7.62x39mm Questions

    Quote Originally Posted by Ghost-6 View Post
    Thanks guys!

    Do more XCR guys buy a barrel and get it turned down or just buy it short? Is there a gunsmith who cuts/flutes/crowns that anyone will recommend? The class 3 paperwork will take a looooong time so I can research smiths but I'd like to hear if anyone knows who does good work...
    Steve at ADCO....but if you flute, specify you want the flute or rib to start at 12 o'clock.

    Most everyone turns it down....getting factory short bbls from RA is not easy. But...if you go that route you may need to order or drill out your gas dial and you may be porting up sizes in the bbl.
    "Necessity is the plea for every infringement of human liberty. It is the argument of tyrants; the creed of slaves."-William Pitt the Younger

  8. #7
    XCR Guru Merlin's Avatar
    Join Date
    Sep 2007
    Posts
    5,840

    Re: SBR in 7.62x39mm Questions

    I don't think we had a definitive answer if a 16"-18" 7.62 barrel can be fluted. Also from what I gathered from questions I posed to Kermit about the factory 12" 7.62 barrels is that they are as 'thin' as they can be already.


    "Be Vigilant and Safe!!"
    "Molon Labe!!"
    "It Is A Weak Man Who Urges Compromise!!"

  9. #8
    XCR Guru Sean K.'s Avatar
    Join Date
    Nov 2008
    Location
    AZ
    Posts
    21,865

    Re: SBR in 7.62x39mm Questions

    Quote Originally Posted by Merlin View Post
    I don't think we had a definitive answer if a 16"-18" 7.62 barrel can be fluted. Also from what I gathered from questions I posed to Kermit about the factory 12" 7.62 barrels is that they are as 'thin' as they can be already.
    This is true....the HBar obviously has a good sized 7.62 hole in it....might not be enough meat to really flute.

    Sean
    "Necessity is the plea for every infringement of human liberty. It is the argument of tyrants; the creed of slaves."-William Pitt the Younger

  10. #9
    Rifleman Ghost-6's Avatar
    Join Date
    Nov 2011
    Posts
    125

    Re: SBR in 7.62x39mm Questions

    Can someone tell me how to get ahold of Kermit? My guess is the wait for a 12" 7.62 barrel might be biblical.

  11. #10
    Expert cjt50's Avatar
    Join Date
    Jun 2010
    Location
    Tampa Bay
    Posts
    772

    Re: SBR in 7.62x39mm Questions

    His full contact info is somewhere on the forum. Can't find it right now because of the "DB" errors. His forum user name is Gramps96kz. Send him a PM.

    ETA: his email is in the 1st post of this thread;

    https://xcrforum.com/index.php/topic,13535.0.html

    You could also PM another forum user, Navalbeaver, he might be able to help as well.
    "Tis better to be silent and be thought a fool, than to speak and remove all doubt." - Pres. A. Lincoln

Page 1 of 3 123 LastLast

Sponsors

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Similar Threads

  1. 7.62x39mm Update
    By kolob in forum 7.62x39mm
    Replies: 315
    Last Post: 04-03-2012, 01:16 PM
  2. 7.62x39mm TSX
    By M993 in forum 7.62x39mm
    Replies: 8
    Last Post: 07-18-2010, 12:11 AM
  3. Thinking about a XCR 7.62x39mm
    By matai in forum 7.62x39mm
    Replies: 3
    Last Post: 05-08-2010, 05:49 PM
  4. Nammo 7.62x39mm
    By M993 in forum 7.62x39mm
    Replies: 1
    Last Post: 05-06-2010, 10:58 AM
  5. Non-Usable Ammo For 7.62x39mm XCR??
    By ZackAttack in forum 7.62x39mm
    Replies: 68
    Last Post: 03-11-2009, 07:04 PM

Search tags for this page

10.5 inch 7.62x39 barrel

,

7.5 barrel 7.62x39mm ballistics

,
7.62x39 10.5 velocity
,
7.62x39 7.5 barrel velocity
,
7.62x39 ballistics out of a 12.5 barrel
,

7.62x39 ballistics sbr

,
7.62x39 out of 10 inch barrel vs 12.5 inch barrel
,

7.62x39 sbr ballistics

,

7.62x39mm 7.5 barrel

,

7.62x39mm sbr ballistics

,
7.62x39mm sbr best barrel length
,
minimum barrel length to stabalize 7.62x39mm
Click on a term to search for related topics.