A tale of four rifles. Two M70's in 7x57 and two M70's in .30-06.
It's hard to believe how time flies sometimes. But some 10 years plus ago I bought a M70 FW in 7x57 for my rather young son and not too long after that a M70 FW in .30-06 for my wife. Two calibers that I had never owned before....yes including the venerable 'turdy odd six.
Well load development was a breeze with both rifles. Bullet wise I wanted to stay on the lighter side with recoil being a concern for both wife and son. I also wanted to stay with my favorite North Forks bonded cores.
No problem, the 140gr for the 7 and 165gr for the 30, a dose of IMR4350 behind each and wham bam it was done quickly. 1" or better groups with both rifles. Time to go hunting and I was very happy with the bullet performance.
So now the boy has the 7x57 at his house, but still have the .30-06. Well I wanted a 7x57 for myself and decided also on picking up another .30-06, both of these of the Super Grade flavor.
So it would seem reasonable to expect those loads to repeat in the new rifles. Reasonable but in reality it hasn't been so. I struggled with the lighter bullets in both of these rifles. The only decent results I got was with the .30-06 and using Winchester Staball 6.5 with 1.25-1.5" groups, not bad but not great either. All other combinations were in the 2" or worse groups at 100 yards. I just won't accept that.
So on to 160gr for the 7x57 and 180gr for the .30-06 I've gone now. First results with IMR4350 didn't result in much improvement. So on to Vihtavuori N160 and things improved a bit but still not great. It was time to then try and old friend, H4831. It wouldn't be the first time that when going to heavier for caliber bullets that this powder worked out for me. Results are preliminary and I still have work to do to ensure repeatability, but today's results were very encouraging with a sub 1" group in the .30-06 and a 1" group in the 7x57.
H4831 will never be a fan of those seeking maximum velocity, but I load for accuracy. I'd rather miss small going slower than miss bigger going faster.
It seems just odd to me how two rifles of the same caliber from the same manufacturer, virtually identical except for the stock can shoot so differently.