Results 1 to 6 of 6

Thread: 300blk rifle in a regular length barrel

  1. #1
    Join Date
    Dec 2012
    Posts
    251
    Feedback Score
    3 (100%)

    300blk rifle in a regular length barrel

    I recently plunged into the 300blk pool with a factory upper for one of my sbr's. Having done the reading for years, I get that the original design philosophy and use case was for short barreled suppressed application. And I really like it.

    So now I got to thinking; how would shooting 125gr supers out of a 14.7 or 16" barrel stack up against 5.56 or 7.62AK? In terms of ballistics and terminal performance, do the supersonic rounds hang in better than the subs past 200 or 300 yards?

    I'm currently swimming in 5.56, so we're not talking replacement here. Just curious if I could make a go-to out of it. Anyone doing this or have any great insights? As far as gun buying goes, this should be like my 127th priority, but we know how that works out. You get the bug, you get the bug. Someone talk me out of trying this.

  2. #2
    Join Date
    May 2011
    Posts
    86
    Feedback Score
    1 (100%)
    The SuperSonics in a longer barrel should equal or better the 7.62x39 especially with the better choices in bullets available.

  3. #3
    Join Date
    Dec 2015
    Posts
    701
    Feedback Score
    2 (100%)
    Quote Originally Posted by nick84 View Post
    I recently plunged into the 300blk pool with a factory upper for one of my sbr's. Having done the reading for years, I get that the original design philosophy and use case was for short barreled suppressed application. And I really like it.

    So now I got to thinking; how would shooting 125gr supers out of a 14.7 or 16" barrel stack up against 5.56 or 7.62AK? In terms of ballistics and terminal performance, do the supersonic rounds hang in better than the subs past 200 or 300 yards?


    I'm currently swimming in 5.56, so we're not talking replacement here. Just curious if I could make a go-to out of it. Anyone doing this or have any great insights? As far as gun buying goes, this should be like my 127th priority, but we know how that works out. You get the bug, you get the bug. Someone talk me out of trying this.
    May be helpful


  4. #4
    Join Date
    May 2015
    Posts
    240
    Feedback Score
    0
    7.62x39 is gonna give you more energy vs supersonic .300bo, but shooting ADI MSR Sierra Matchking .300bo (125gr. super) thru my PSA 16” 300bo upper still groups better than my PSA 16” 7.62x39 upper shooting Golden Tiger steel case or surplus Yugo m67. Now if I went up to Hornady SST Black 7,62x39 it might be different, but for what that costs I might as well buy Hornady Black 6.5 Grendel.

    Going from 8” to 16” barrel is only gonna net you another 200 to 300 FPS. I first bought a 16” .300bo upper before I got in to braced pistols and added an 8” .300bo so I put a red dot on the 8” for subs and a 1-4x scope on the 16” but shooting them side by side, not much difference.

    If you’re wanting to shoot out to 300 yards, 6.5Grendel is a much better caliber.

    Having an AR in 7,62x39 is a good option, steel case ammo is cheap & plentiful, but very limited in bullet selection.

  5. #5
    Join Date
    Dec 2012
    Posts
    251
    Feedback Score
    3 (100%)
    Quote Originally Posted by Mrgunsngear View Post
    May be helpful
    Excellent. Pretty much what I was looking for. Thanks for the video.

  6. #6
    Join Date
    Nov 2010
    Location
    Michigan
    Posts
    3,637
    Feedback Score
    19 (100%)
    Quote Originally Posted by nick84 View Post
    So now I got to thinking; how would shooting 125gr supers out of a 14.7 or 16" barrel stack up against 5.56 or 7.62AK? In terms of ballistics and terminal performance, do the supersonic rounds hang in better than the subs past 200 or 300 yards?

    *** You get the bug, you get the bug. Someone talk me out of trying this.
    If you cherry-pick the right cartridges, 300BLK looks decent compared to 5.56 in a 16", mostly for muzzle energy and momentum (power factor). But the bullet starts slow and the BC's are not impressive for anything that will go over 2000fps, so it's a medium range cartridge, at best, and compares to the 762x39, not in a good way. If you're shooting beyond 300 yards a good 5.56 OTM/BTHP load will beat it badly.

    The potential benefits: larger and heavier bullet, if that matters (it probably doesn't); can switch between subsonic and supers in the same upper without adjusting anything; plays nicely with suppressors; may be legal for deer in a few states where .223 is not; good option if you have an existing SBR and suppressor setup and want the ability to reach out a little farther in the same caliber.

    It's really a niche option, not a jack of all trades.
    ____________________________________________________________________________________
    Use InfoGalactic instead of Wikipedia - avoid Wikipedia's left bias

    https://infogalactic.com/info/Main_Page
    ____________________________________________________________________________________

    Product reviews stating "Only 4 stars because I haven't used it yet" are an idiot's signature.
    ____________________________________________________________________________________

Bookmarks

Posting Permissions

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