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Old May 6, 2013, 08:05 AM   #3
Bart B.
Senior Member
 
Join Date: February 15, 2009
Posts: 8,927
Sierra's 30 caliber 168 has a notorious record for long range competition. It's boattail shape isn't right to keep the bullet super sonic through 1000 yards unless it leaves the barrel at least 2650 fps. With normal, safe, peak pressures, you'll need a 24 inch barrel; 26 inch in some instances. If yours has a 20 inch barrel, forget it. Slug your barrel and if it's groove diameter's bigger than .3080", Sierra's probably won't produce best accuracy anyway. You may have to find match bullet with a larger diameter, such as Lapua's D166 at 200 grains and a .3095" diameter, especially if the groove diameters as big as .3085" or more.

44 grains of IMR4064 was "the" standard match-winning record-setting load for 168's in M14NM rifles when the .308 was popular in high power competition. Worked great up through 600 yards, but the M14's 22 inch barrel sometimes didn't shoot it fast enough to remain supersonic through 1000 yards. Which is why Sierra's 180's were the favorite of the Army's team for long range loads. In rifles with 24 to 26 inch barrels, that load for 168's usually shot them fast enough to stay supersonic through 1000 yards

I suggest Sierra's 175-gr. HPMK bullet; much better for 1000 yard matches. Stays supersonic all the way even from 22 inch barrels.

Also, if your Sako has a muzzle brake, that'll have to be removed for NRA competitions; they're not allowed. Besides, they cause accuracy problems when it's raining.
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