Friday, August 04, 2017

One last thing from the other day

I'd picked up a box of Sig's new .300 Blackout hunting ammo: 120-grain solid copper hollowpoint.  Supposed to run 2250feet per second, and a little digging around shows some very impressive gel block tests on expansion.

This is a long bullet, and the cartridge looks halfway like something from a sci-fi movie.  Not having any gel I just wanted to see how this cycled through my rifle, and what kind of accuracy I would get.*

Not bad; I'm blaming myself for the left-to-right spread.  But why only four holes?  Because the first one I fired hit WAY high; as in 'if there hadn't been some unperforated paper up there I'd never have seen where it went' high.  So I aimed at the lower diamond for the other four
which put them in the upper diamond.  With the usual load I shoot, at 100 yards the point of impact is about an inch above point of aim, so at close to the same velocity the Sig bullets hit about 4.5" higher.  Which is interesting.  I need to take this stuff to a place I can get longer distance and see what kind of trajectory is going on.

*Remember that this was after forty-something .45-70 rounds; probably should have shot this first

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