The rush to short barrel Grendels

[LRRPF52]

I know your looked upon very highly here...nearly God like...but your numbers are cooked to make your point. Import factory ammo disigned for guns built in the late 40's, up against modern factory guns and like ammo!

My 16" 7.62x39 AR's with hand loads equal my 6.5 velocities. I've been using CFE BLK powder and staying inside max loads. I have developed quite a new feeling for the hated AK round!

You're making the same basic mistake I used to do when all we had was muzzle velocity data, not downrange data from ballistics calculators.

16.3" AK is roughly 80-150fps faster at the muzzle than a 10.5" Grendel shooting the same bullet weight. Now watch what happens once both have reached 100yds:

10.5" Grendel, 123gr SST with a .462 G1 BC (derated actual BC, not inflated published BC), 2210fps

100yds 2038fps 1135ft-lbs

125yds 1997fps 1089ft-lbs

150yds 1956fps 1045ft-lbs

200yds 1875fps 961ft-lbs

225yds 1836fps 921ft-lbs

16.3" 7.62x39, 123gr FMJ, .266 G1 BC, 2350fps

100yds 2047fps 1144ft-lbs

125yds 1975fps 1065ft-lbs

150yds 1904fps 990ft-lbs

200yds 1768fps 854ft-lbs

225yds 1703fps 792ft-lbs


So now you're left having to explain to me why I should carry around a longer rifle to get less performance. You're not going to do yourself many favors with increasing the velocity with it by hand-loading, because the 7.62x39 .310" bullet selection doesn't break .300 G1, so no real practical differences in performance when you push it a little, and bolt thrust is considerable with the high case taper in that cartridge.

No deities here, and no hate, just applied physics. If you think I'm wrong, feel more than free to lay out the ballistic argument and I'll go get dies and components to load up my 20" SKS and 16.3" AKs....but I can save you the effort and tell you they'll probably be for sale sooner than later while I enjoy my 12" and 10.5" Grendels.

Your argument is an excellent case study though for those who might not have seen the comparison side-by-side of how shorter barrel Grendels exceed the ballistic performance of even the 20" SKS as you start to look at 125yds and farther.

Now if you're shooting stuff within 100yds in really tight terrain, then absolutely yes, you will have slightly faster impact speeds, but from my POV, that's another case for the shorter weapon vs a much longer barrel, that also allows you to punch into occasional farm fields and still maintain over 900ft-lbs past 225yds, whereas the 7.62x39 from a 20" SKS at 2400fps will still not maintain 900ft-lbs to 200yds, and the 16.3" only keeps 900ft-lbs out to 175yds.

So you look down at the two options and see that there aren't a lot of selling points for the 7.62x39 no matter how you slice it.