6br vs 6ppc

66-68 gr bullets and 100-200 yards. In 100-200 yard benchrest I never see the 6br on top,only the 6ppc. I'm just curious on why that is.
 
The faster that you spin a bullet, the more effect the distance between between its center of mass and geometric center has on accuracy. (This is primarily be cause by jacket thickness runout, but may also be affected by lack of core homogeneity.) As distance to target increases wind becomes exponentially more of a factor, and at some point giving away some of the accuracy lost to increased bullet rotational speed to gain the advantages of the higher BC bullets that it allows passes the tipping point. The average loss is less than the average gain. The only reason for increasing twist rate is to allow the use of longer bullets.

I know an experienced short range benchrest competitor who had, some time in the past shot a 6BR. He said that it was competitive. He dealt with the capacity issue by using slightly slower powders that would fill the case. I am pretty sure that he used twists and bullet weights that are typical of those used with 6PPCs for short range (1-200yd.) competition. I should note that at the time of our conversation he was shooting a 6PPC. One might logically conclude that the BR did not have an advantage.

A couple of friends have slow twist 6BR varmint rifles that were built by gunsmiths that compete in and build short range benchrest rifles. If they tune for peak accuracy, with different components than they use for shooting critters, their rifles produce groups (perfect conditions) in the low twos with some in the ones. They would have to be shot as HVs, but I wouldn't be afraid to shoot them in a match. Interestingly enough, the velocities that produce their best bench groups are slower than many PPC shooters work with.
 
My thoughts would be the 6ppc maybe slightly more accurate at 100/200 yrds. very slightly...
There was a artical back in the day when ppc cases were scarce, one famous shooter, said when he saw the 6BR he had remington(he new someone) send him 20 cases, he had a barrel chambered. He said while the 6BR would shoot,it had more case capicity than was needed..not that it had too much that it had a accuracry problem.
I have a 6BR set up as a light varmint rifle, rifle weighs 10lbs 0oz..I plan to shoot it in a few matches to see how it will perform..
I have shot many groups in the mid .100's with my 6BR's and can not understand why it can not be competitive..At this point in time...
I'm in the process of having a 6ppc built, you know as a spare..

I think the 6BR failed in short range BR due to case problems..when the lapua cases came out that solved any issue there..
as far as it having too much capicity to not be accurate..I have not seen it..I burn 30.5grs of powder and it seems to be insensitive and easy to tune.
As far as shooting groups in the .100's at a match,I have not been able to do it..but have been close a few times..
 
Gotta jump on here with my experiences with both this past Summer, competing in local 1,2,& 300 yd. benchrest varmint match's. 10 ring at all 3 distances are 1/2" in diameter, to score an "X" the entire shot hole must be inside the 10 ring. Anyway, fired double match's, one with a Bat/Bartlein 6ppc and another with one of my 14 twist 6BR's. Both with NF BR 12-42x's. Would fire one relay with the ppc, then the next relay with the 6BR, or BR first & ppc second. At 1 & 200 yds. the ppc would always produce the smaller 5 shot group with a higher X count, edging out the BR by just a little. But, at 300 yds., the BR would always have a smaller group with a higher X count. I always had the feeling that the 6ppc was running out of steam at 300, but the 6BR was starting to come on strong. Very unscientific I understand, just what I noticed when competing with them side-by-side.
 
Provocative question

I don't think the 6PPC is more accurate than the 6BR. I think the probability of getting your hands on a competitive 100/200 yard rifle weighs heavily on the PPC side of the scale.

Notice the 100/200 qualification...move that scale downrange a few hundred yards and the BR rifles begin to weigh more. Keep going and one .360 Kubla Khan Improved will outweigh them all.

Competitive benchrest rifles are special purpose. Drift away from the purpose and you gotta have something different to be consistently competitive.
 
Short range benchrest rifles are mission specific, and rule book derived. Change the mission and or the rule book and the design of competitive rifles changes with them. A short range benchrest rifle may not be competitve through all conditions, at longer ranges, and a longer range benchrest rifle will probably not fit within the rule book of shorter range competition. Different rules, different ranges, different rifles win. The slightly larger case of the BR has an advantage for making velocity with longer heavier bullets whose higher BCs start to have an advantage as ranges increase. At shorter ranges, BC is less important, and bullets that allow a slower twist, paired with a cases that are closer to full may have some slight advantage.
 
Boyd Allen said:
Short range benchrest rifles are mission specific, and rule book derived. Change the mission and or the rule book and the design of competitive rifles changes with them. A short range benchrest rifle may not be competitve through all conditions, at longer ranges, and a longer range benchrest rifle will probably not fit within the rule book of shorter range competition. Different rules, different ranges, different rifles win. The slightly larger case of the BR has an advantage for making velocity with longer heavier bullets whose higher BCs start to have an advantage as ranges increase. At shorter ranges, BC is less important, and bullets that allow a slower twist, paired with a cases that are closer to full may have some slight advantage.
Click to expand...

Yeah...that's better said.
 
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