A good bullet for a 6.8 SPC AR?

Fishaholic · Mar 1, 2013

I've built an AR in 6.8 SPC recently and wanted to get opinions on a good bullet(s) for both hunting and the range. The only ones I've shot so far are the Hdy SST 120gr off the shelf ammo and Sierra Match Kings BTHP in 115gr reloads. They both shoot GREAT but have very different POI for some reason. I haven't figured out why and want to zero my rifle for only one good load. I plan on varmit shooting and also antelope if I ever get drawn for them. Not sure any lighter than 110-115gr or heavier than 120 would be wise for the antelope. Any help would be appreciated.

misplacedtexan · Mar 1, 2013

The ballistic coefficient of the bullets, and weight (though not drastically at 5 grains) will affect flight path. The bullets are shaped/made different, so the fly different.

Darkker · Mar 2, 2013

Yep,
different ogive's, different tail angles, different jacket material, different bullet length requiring different amounts of twist, different bearing surfaces-so different acceleration times and changed harmonics when exiting the barrel.

Fishaholic · Mar 2, 2013

Thanks guys. I was just trying to get an idea of about the heaviest bullet that will still shoot good enough and at the required range for antelope. I think a 130 will lose too much velocity since the 6.8 is a lot smaller volume of powder than the .270 Win. There aren't that many manu. of .277 bullets in the 110-125gr range so the options are somewhat limited. Given the scarcity of almost any kind of bullet these days doubles my effort to find some.

misplacedtexan · Mar 2, 2013

It's a trade off, it'll lose speed, but carries extra energy in its mass. Lighter bullets carry speed, but less mass. If you can push the lighter bullets fast enough it makes up for the difference, but at times its hard to do that, maintain good grouping, and not exceed pressure levels for the firearm.

Twodogs · Mar 3, 2013

I've been loading for the 6.8mm for a while now the 120gr sst and the sierra 110gr prohunter are two great hunting bullets so is the 100gr acubond also have shot the 90gr sierra and really like it for coyotes.

Fishaholic · Mar 3, 2013

Thanks Twodogs. I've got some Hdy 110gr BTHP on order to try. I also have some 110gr prohunters on order figuring they would be a good hunting bullet. The 115gr match kings are awesome but shoot a lot different than the 120 SST's. I'm just trying to find one or maybe two bullets that work good for what I want to use it for and then just reload for quantity after that. Thanks for all the info from everyone.