Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Rifles, Bullets, Barrels & Ballistics

Rifles, Bullets, Barrels & Ballistics Applied Ballistics


Reply

Nosler Accubond Long Range problem

 
LinkBack Thread Tools Display Modes
  #78  
Old 09-07-2013, 07:58 PM
Platinum Member
 
Join Date: May 2012
Location: N.D.
Posts: 3,164
Re: Nosler Accubond Long Range problem

To me this smells like a slightly loose barrel dimension coupled with a rather stiff pill that doesn't really like to obdurate. The other pills you used the flew well were either softer ( berger and sierra) or had longer bearing surface (regular nos) that allowed them to slug up and/ or follow the bbl better. I'd bet these barrels would puke badly on original barnes X. I'd guess as you turn up the heat on these nosler lr slugs they are getting kicked around as they exit the bbl., hence why they show better accuracy at lower pressures.

I picked up a box of the 7mm 150 grain accubond lr pills today at my local lgs. I'm going to tear them a new one with my 10" twist 7stw; I'll let you all know what they do in the next couple of weeks. This particular barrel seems to be a nosler barrel so I'm hoping for decent results.
Reply With Quote
  #79  
Old 09-07-2013, 09:48 PM
Platinum Member
 
Join Date: Dec 2008
Location: Grantsville Utah
Posts: 3,500
Re: Nosler Accubond Long Range problem

Quote:
Originally Posted by Lefty7mmstw View Post
To me this smells like a slightly loose barrel dimension coupled with a rather stiff pill that doesn't really like to obdurate. The other pills you used the flew well were either softer ( berger and sierra) or had longer bearing surface (regular nos) that allowed them to slug up and/ or follow the bbl better. I'd bet these barrels would puke badly on original barnes X. I'd guess as you turn up the heat on these nosler lr slugs they are getting kicked around as they exit the bbl., hence why they show better accuracy at lower pressures.

I picked up a box of the 7mm 150 grain accubond lr pills today at my local lgs. I'm going to tear them a new one with my 10" twist 7stw; I'll let you all know what they do in the next couple of weeks. This particular barrel seems to be a nosler barrel so I'm hoping for decent results.
Lefty......I have seen that happen only velocity usually is the way to go to make a stiff bullet obturate (more pressure). I know Bill Stieger (sp)? Bitterroot Bullets, use to say to load up his thick jacket bullets and they would obturate better. It seems more like velocity "causes" the problem in this case??.......Rich
Reply With Quote
  #80  
Old 09-08-2013, 04:30 AM
Platinum Member
 
Join Date: May 2012
Location: N.D.
Posts: 3,164
Re: Nosler Accubond Long Range problem

Quote:
Originally Posted by elkaholic View Post
Lefty......I have seen that happen only velocity usually is the way to go to make a stiff bullet obturate (more pressure). I know Bill Stieger (sp)? Bitterroot Bullets, use to say to load up his thick jacket bullets and they would obturate better. It seems more like velocity "causes" the problem in this case??.......Rich
Not nessesarily. If the bore is out of whack enough that it'll never engrave properly, the only choice for any real accuracy is to drop the pressure as the bullet exits by using a faster powder or dropping your charge back quite a bit.

I remember one 243 load my pops was killing 'yotes with that would pop off at just north of 2,000 fps; the load was in the sub 1/2 moa range for 5 and he'd regularly knock off coyotes with the rifle when we were out bird hunting at pretty stiff ranges. Years later we tried to crank up those bullets in the same rifle and they would spray no matter the powder we used. The cream puff load was letting the bullet loose easier.
I'd bet if the op went to say 4064 or 4320 instead of 4831 his groups would come in as the pressure would be off more at bullet exit. He'd have to deal with lower load density, but it'll shoot better.
Reply With Quote
  #81  
Old 09-08-2013, 06:59 AM
Platinum Member
 
Join Date: Apr 2005
Location: Alaska
Posts: 3,512
Re: Nosler Accubond Long Range problem

I thought the OP said he had the same problem with two different barrels. What are the odds of that? Two barrels manufactured with improper bore diameters?
Reply With Quote
  #82  
Old 09-08-2013, 09:20 AM
Official LRH Sponsor
 
Join Date: Jun 2004
Location: Fort Shaw, Montana
Posts: 6,831
Re: Nosler Accubond Long Range problem

Quote:
Originally Posted by Lefty7mmstw View Post
Not nessesarily. If the bore is out of whack enough that it'll never engrave properly, the only choice for any real accuracy is to drop the pressure as the bullet exits by using a faster powder or dropping your charge back quite a bit.

I remember one 243 load my pops was killing 'yotes with that would pop off at just north of 2,000 fps; the load was in the sub 1/2 moa range for 5 and he'd regularly knock off coyotes with the rifle when we were out bird hunting at pretty stiff ranges. Years later we tried to crank up those bullets in the same rifle and they would spray no matter the powder we used. The cream puff load was letting the bullet loose easier.
I'd bet if the op went to say 4064 or 4320 instead of 4831 his groups would come in as the pressure would be off more at bullet exit. He'd have to deal with lower load density, but it'll shoot better.
While I agree that a faster burn rate powder can sharpen the pressure spike at ignition, I do not feel that it will be enough to bump up these bullets. IF a bullet is shooting very well at lower velocity, its matched to the bore plenty well, added more powder will simply steepen the pressure curve which should do nothing but bump up the bullet more then the lower pressure loads so I am not sure you theory will work.

Possible, at this point, would be willing to try anything!!!
__________________
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com

allenmagnum@gmail.com
Reply With Quote
  #83  
Old 09-08-2013, 09:22 AM
Official LRH Sponsor
 
Join Date: Jun 2004
Location: Fort Shaw, Montana
Posts: 6,831
Re: Nosler Accubond Long Range problem

Quote:
Originally Posted by phorwath View Post
I thought the OP said he had the same problem with two different barrels. What are the odds of that? Two barrels manufactured with improper bore diameters?
He had tested the Long Range Accubond and the Ballistic Tip, both have similar jacket design, both very thick heavy jacket designs.

Still feel my first step would be to try a conventional cup jacketed bullet just to see if its a bullet design issue and if it repeats the same results, its very likely a mechanical issue.
__________________
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com

allenmagnum@gmail.com
Reply With Quote
  #84  
Old 09-08-2013, 10:05 AM
Silver Member
 
Join Date: Oct 2007
Location: Flat Rock, Michigan, USA
Posts: 137
Re: Nosler Accubond Long Range problem

Quote:
Originally Posted by Engineering101 View Post

The barrels I referenced are both conventional 1 in 10 twist, 6 groove, new surplus factory Savage 26 inch stainless barrels in varmit contour that I bought off Numrich’s site for $95 apiece. Obviously being the same “part number” they could have a similar defect. But I don’t know what kind of defect you could put in a barrel to cause it to shoot better than MOA and then quit shooting totally at a specific velocity? I bought the second barrel because of the problems I was having with the first one.
...
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes



All times are GMT -5. The time now is 09:28 PM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC