Re: strange load question
Here's some load data I got directly from Berger for their 155 and 168 VLD's
168 Grain IMR 4064 38.5 2450 42.6 2688 99.60%
155/155.5 Grain IMR 4064 40 2529 44.5 2800 103.20%
42.5 gr looks like too much powder. I'd start lower with the 155 then work up. As with any gun/load combo you'll have to test. The biggest difference in the bullets that would affect accuracy is BC difference. I"m guessing you have a 1/12 twist which is fine for those two bullets.
I've found that I can shoot anything from 35 to 65gr bullets in my .223s with the same accuracy level but the amount of powder and speed changes. Each bullet weight has a sweet spot of powder that delivers the most accuracy. In my .223 the powder charges differ by 1.5 gr from lightest to heaviest.
So you need to test with the new bullet and start out with a load at the lower end of the chart and work up...That's my 2cents.
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