close

Privacy guaranteed - Your email is not shared with anyone.

75 gr. through 1:9 twist??

Discussion in 'Black Rifle Forum' started by Smokin45, Nov 30, 2012.

Thread Status:
Not open for further replies.
  1. Smokin45

    Smokin45

    Joined:
    Oct 15, 2012
    Messages:
    500
    Likes Received:
    68
    Location:
    Dirty Duval, FL
    Just picked up some TAP 75 gr. and was wondering how it would shoot through a 1:9 twist barrel? I will be using it with a Armalite AR with a 16" heavy barrel if that makes a difference..
     
  2. larson1122

    larson1122

    Joined:
    Jan 30, 2012
    Messages:
    1,801
    Likes Received:
    0
    Location:
    Minnesota
    The only way to know for sure is to shoot it and find out. Some barrels will shoot it just fine and others wont.
     

  3. Armchair Commando

    Armchair Commando Long Range Guru

    Joined:
    Jan 10, 2006
    Messages:
    1,804
    Likes Received:
    1
    Location:
    Bunker in the Midwest
    My 1-8 loves 77gr Sierra Matchkings. Only way to know is to shoot it.

    posted using Outdoor Hub Campfire
     
  4. faawrenchbndr

    faawrenchbndr CLM

    Joined:
    Nov 24, 2005
    Messages:
    37,035
    Likes Received:
    1,245
    Location:
    east of East St Louis

    :agree:
     
  5. cowboy1964

    cowboy1964

    Joined:
    Sep 4, 2009
    Messages:
    22,803
    Likes Received:
    4,445
    Location:
    U.S.A.
    I'm only shot 75gr TAP through 1:9 at 25 yards. Works ok but that distance really doesn't prove anything.

    I've since decided to standardize on 1:7 twist so I can shoot 77gr Mk 262 and such.
     
    Last edited: Nov 30, 2012
  6. Travclem

    Travclem Badass Member Lifetime Member

    Joined:
    Aug 4, 2008
    Messages:
    6,775
    Likes Received:
    15
    Location:
    Lubbock, TX
    My 1:7 ARs love it, my best friend's 1:9 loves it, and my 700P 1:10 loves it. My 75gr Hornady OTM handloads are good out of all of our guns out to 200yds. I haven't shot them further than that on paper. I have killed a couple hogs at further distances than that so I assume they are still stable enough.

    My 700p shoots cloverleaf groups at 100 and 1-1.25" at 200 with this load and according to the interwebz it's impossible due to the 1:10 twist.

    I have yet to find a gun that wouldn't shoot it, but go shoot some out of yours to be sure. That's the only way to know for sure.
     
  7. Matthew Courtney

    Matthew Courtney Instructor #298

    Joined:
    Oct 14, 2002
    Messages:
    3,644
    Likes Received:
    5
    Location:
    Lake Charles
    More than being a rifle to rifle thing, its an environment to environment thing. Gyroscopic stability requires more rpm's in environments with more friction from the bullet passing through the air as well as higher rpm's when the center of pressure is farther forward. In less dense air, friction is less. Temperature, humidity, and low barometric pressure lessen the density of the air and allow bullets to stabilize at lower rpms.
     
  8. Foxtrotx1

    Foxtrotx1

    Joined:
    Jan 29, 2010
    Messages:
    4,036
    Likes Received:
    3
    Location:
    Scottsdale AZ
    So good at 7,000 feet. Not so good at 2000?
     
  9. Travclem

    Travclem Badass Member Lifetime Member

    Joined:
    Aug 4, 2008
    Messages:
    6,775
    Likes Received:
    15
    Location:
    Lubbock, TX
    That's the idea but I can tell you that mine work at 3,256 ft. (Lubbock, TX), 2,605 ft. (Post, TX) and 3605 ft. (Amarillo, TX).
     
    Last edited: Nov 30, 2012
  10. Gunnut 45/454

    Gunnut 45/454

    Joined:
    Jun 20, 2002
    Messages:
    12,129
    Likes Received:
    9
    The 75gr Horn match bullets shoot fair out of my 1:9" and Sav 1:9" good enough to use for close work. But the 75gr Amax shoots real good in my PSA 1:7" and yes you can load them to fit the Mag.:supergrin:
     
  11. Steve in PA

    Steve in PA

    Joined:
    Mar 1, 2000
    Messages:
    2,337
    Likes Received:
    52
    Location:
    Pennsylvania
    Both my Savage 12FV and Bushmaster rifles shoot the 75gr bullets just fine. Both are 1:9 barrels.
     
  12. smokin762

    smokin762

    Joined:
    Apr 19, 2009
    Messages:
    5,250
    Likes Received:
    4
    Location:
    Ohio
    My Bushmaster AR has a 20” 1/9 barrel. It shoots Hornady 75gr Superformance at 100 yards very nicely with iron sights. I tried it with the scope and kept tight groups.

    As said, you just need to try it out.
     
  13. WoodenPlank

    WoodenPlank Who?

    Joined:
    May 15, 2010
    Messages:
    7,958
    Likes Received:
    6
    Location:
    NW Florida
    As others have said, try it and see.

    Longer barrels are more likely to see good results than shorter, however. Since you asked about TAP, you might want to check out some of the lighter 62-64 grain bonded soft points, Gold Dot JHP, or the various loads out there using Barnes TSX bullets.
     
  14. WinterWizard

    WinterWizard

    Joined:
    Jan 17, 2012
    Messages:
    1,417
    Likes Received:
    7
    I have wondered about this, as well. The packaging even states "1-9" twist or faster," so 1-9" should be good to go. However, there is the occasional report from shooters that their 1-9" barrel didn't stabilize this round. It does seem to be a very, very small minority, though. I bet 19 in 20 barrels with a 1-9" twist will stabilize this round just fine. But, like others have said, no way to be sure until you shoot it at about 200 yards and check for keyholes, etc...

    I wonder what Hornady would say if someone with a 1-9" twist barrel contacted them to say their barrel couldn't stabilize this round? Since it's even on their package, couldn't that be false advertising or misleading? I bet they would send out some replacement rounds, maybe 60gr Tap or something similar if you made a big enough stink.
     
    Last edited: Nov 30, 2012
  15. brisk21

    brisk21

    Joined:
    May 13, 2008
    Messages:
    4,206
    Likes Received:
    16
    Location:
    Michigan
    I know a dude who just got a DPMS with a 1-9 twist. He said that the 100yd groups opened up to about 6-7 inches with 75gr. bullets. He was holding 1-2 inch groups with 55gr. ammo.
     
  16. cowboy1964

    cowboy1964

    Joined:
    Sep 4, 2009
    Messages:
    22,803
    Likes Received:
    4,445
    Location:
    U.S.A.
    Possibly. OTOH, they make no claims about accuracy at distance, so...
     
  17. WinterWizard

    WinterWizard

    Joined:
    Jan 17, 2012
    Messages:
    1,417
    Likes Received:
    7
    Yeah, but if it's keyholing, it's obviously not stabilized, and there is physical proof by way of the paper target. If they say a 1-9" twist will stabilize this bullet and the bullet is tumbling sideways through the air from a 1-9" barrel, I believe that's a problem. Of course, there are small discrepancies from barrel to barrel. Your 1-9" may actually be a 1-8.8" or a 1-9.2", etc. That is where the problem lies likely.
     
  18. jrs93accord

    jrs93accord

    Joined:
    Jul 10, 2005
    Messages:
    6,209
    Likes Received:
    262
    Location:
    Pensacola, FL
    Typically, a 1:9 barrel is good for 55gr. to 72gr. ammo. When you get into the 75gr. and higher, 1:8 or 1:7 is the best route to take. They can stabilize the heavier round better. This is not a hard fast rule, but more of a guideline. Sometimes, it can depend on the load of the heavy round as to what kind of performance you will get in a 1:9 barrel. Personally, I have a dedicated 1:8 (18") AR (Mk12 Mod0) for shooting heavy ammo (in my case, 77gr.). Everything else is for the .55gr. - 63gr. ammo. My advice, if you want to shoot a heavy round, build an AR that is more suited for it.
     
  19. Warp

    Warp ΜΟΛΩΝ ΛΑΒΕ

    Joined:
    Jul 31, 2005
    Messages:
    16,541
    Likes Received:
    478
    Location:
    Atlanta
    Good reason to buy a proper 1:7 barrel if you ask me
     
  20. smokin762

    smokin762

    Joined:
    Apr 19, 2009
    Messages:
    5,250
    Likes Received:
    4
    Location:
    Ohio
    :upeyes:
     
Thread Status:
Not open for further replies.