Re: Change weight of bullet and nothing else how much load tuning do i need?
I ran into the same situation with the 65gn V-Max's. I worked up an accurate load using 39.5gn of Varget/CCI BR2's and an OAL of 2.2260". These ran at 3511fps and printed .4070" at 100yds. Not the best accuracy I've had from this Win70 HVB, but good enough for vermin.
At the same time I ran low on bullets, I ran low on VARGET. I tried the 70gn NBT/IMR 4895/CCI BR2's/OAL: 2.2495". At 40.5gn's accuracy ran .4015". I tried this load again two days later and accuracy ran out to almost an inch (still scratching my head on that one?). I switched over to the Hornady 75gn HP (#2420) with a stiff load of IMR4895/CCI BR2's and getting great velocity and accuracy. Accuracy is running sub .4" and velocity averages 3602fps. OAL for my rifle is 2.1800".
Now I'm outta IMR4895 and Varget, but since deer season is upon me, I switched to the 95gn Ballistic Tip/44.0gn Viht N560/CCI BR2's/2.2600" at 3144fps and accuracy is running in the .2's. I figured in addition to being an ample bullet for deer it would also suffice for LR "hawgs" and crows. It has not let me down. I took two crows last Saturday at just under 300yds and a whistle pig at 100yds. Not LR but he popped up right on me.
With everything else remaining the same, I would drop the powder charge at least 10% and start back up. That's the safest thing to do. Good luck. JohnnyK.
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