Originally Posted by joe0121
I need a load for 308. But I want a shortish tube say 20 inches in a varmint contour. I'm thinking a light VLD type bullet to make up for the lost MV with a fast twist rate to stabilize it.
I want a light easy to handle rifle that shoot flat enough for ground hogs but still hit at 800 yards.
Think 48 gr's BC2 in front of CCI Benchrest primers and 168gr Amax? Lapua brass, using a lee neck sizer with tight head space.
A 20 inch barrel won't shoot light bullets very fast. I'd suggest at least 26 inches if you want to keep a light bullet from going subsonic at about 900 yards. People tried that length with Sierra's first 155-grain Palma bullet and it often went subsonic at 900 yards. So a 28 inch barrel shooting 155's is probably your best setup for good accuracy through 900 yards. Sierra has a 135-gr. HPMK bullet, but I don't think it would be as good a choice as the 155.
If the powder you mention, BC2 is actually ball C2 powder I'd forget it if accuracy is important. I can't think of anybody winning matches and setting records ever using ball powder of any type. Doesn't matter if it meters very accurate and gives low spreads in muzzle velocity and chamber pressure; ball powders don't have a good track record. Varget and IMR4895 have prooved excellent with light bullets in a .308; they were/are used large lots of Palma ammo for long range competition.
The favorite primer for long range loads these days are Wolf large rifle or large riflt magnum. Made in Russia, they've been used to win a lot of matches setting recoreds along the way. And they seem to keep forever.
Full length sizing the .308 case with a bushing die without an expander ball has been the best choice for accuracy. Neck only sizing never consistantly produced best accuracy. But use a case gage to measure the head to shoulder dimension so you can set the die to push the fired case shoulder back a couple thousandths.
A standard SAAMI dimension chamber may be your best choice. That's the one that, again, typically wins the matches and sets the records. And no tight headspace, either, as there has to be a bit of clearance on the case so the bolt will easily close back into the exact same position for each shot. Tight fits and cases that cause binding never shoot too accurate.