Inconsistency in bullet Projectiles

[STOMP442]

I still don't think its the tip. Berger Bullets are renowned for their match grade quality. I run bergers almost exclusively and noticed the tips you are describing with no noticeable effect on accuracy even at long ranges. I'm thinking inconsistent powder burn or case volumes with the brass. Won't notice it much at 100 yards but shows up more when distance increases. What caliber, powder and brass are you using? What kind of rifle and has it been bedded and floated?

[huntjunkie]

I'm shooting a 7 mag 168 gr Berger VLD Remington brass all have been shot once to "size" the brass for my gun. Trimmed/sized. Federal primers and 62.8 grs 4831sc powder.

2700 mv.

Thanks for all the advise!

 

[STOMP442]

What is your barrel length? 2700 seems a little slow for that bullet and powder charge. Might need to switch powders to gain a little more consistency or adjust seating depth by .005 increments and shoot for group at 200 to see if it will tighten up.

[PRDATR]

I'd be pushing them closer to 2900 to help stabilize them more.

[cbryant11]

What altitude and barrel twist do you have berger has a cool calculator on there site that will tell you if your using enough twist

[huntjunkie]

Yea I was hoping for more speed. 63 grs is the max that the powder manufacture recommends, Berger say 64.

9:1 twist.

[STOMP442]

Try some H4350, R17, ramshot hunter or Retumbo as other powder choices. If your not showing signs of pressure where your at you could always increase carefully in half grain increments and watch closely for pressure signs.

[rossislider]

Hey Stan-

Last week when Steve and I were at the range, he put a 3 shot 100 yard group together so tight that you really couldn't tell if two or three rounds had gone through the target. He is also shooting 4831sc with 150 gr Barnes TTSX. I'll find out his powder weight and muzzle velocity. Maybe we ought to give it a try.

[308Nut]

Tips like that are the norm. Inconsistent meplats have more to do with a variance in bc than raw accuracy. For obvious reasons, varying BC's will = larger groups way down range but not 200 yards. uniforming them won't help that much at shorter ranges.

 

Check your scope's parallax between 100 and 200 yards.

 

Sometimes a load just does not do as well at longer ranges as it does shorter ranges. Sometimes it's the opposite and sometimes it's the same MOA value from 100 yards to 1000 yards.

 

[DanBnAZ]

I had a similar problem with a 270 and it ended up being scope parallax. A new scope with parallax adjustment corrected the issue. I've read from one bullet manufacturer that consistency/uniformity at the bullet base is far more critical than the meplat. Good luck in getting this issue resolved.