LR308 Ladder Test w/H4895

[magnum_99]

I tested my LR308 (Krieger Barrel, DD 12.0 rail, Geissele trigger) with H4895 over a 175 gr. Sierra Match King, Fed210m primer, Win brass, 2.800" C.O.A.L., at 300 yards.

I had been using 44 gr. of Varget (my bolt gun load) and only ever got about .75 MOA out of that in the AR10, and wanted to try really developing a load, and one that was not pushing things on the hot end of the scale.

My loads were as follows:

1-40.0
2-40.3
3-40.5
4-40.8
5-41
6-41.3
7-41.5
8-41.8
9-42

I stopped at 42 grains, anticipating that if I didn't get a load that worked, I would load up a few on the hot end and do the test over again.

As you can see from the photos, I think I got it. I got a 1.53" group from 7 rounds of varying powder charges! I'm a little surprised, but it looks like 40.5-41 grains is the real sweet spot for this rifle.

Now I just have to load up some more in that range and do a little more testing, but my hunch is the results will be similar.

I did not use a chronograph, though I will be doing that on the next test session. I hope the velocity isn't too low.

Here is the rifle:

 

[DRAM40A1]

Re: LR308 Ladder Test w/H4895

Shots 8 and 9 have less vertical dispersion. Are there any pressure signs at 42 grns?

 

[magnum_99]

Re: LR308 Ladder Test w/H4895

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DRA-M40A1</div><div class="ubbcode-body">Shots 8 and 9 have less vertical dispersion. Are there any pressure signs at 42 grns? </div></div>

No pressure sign at all at 42.0 grains. In fact, I get no pressure signs with 44 grains of Varget either, and that is a pretty hot load in a semi.

I think I may play with this load a little and load up some at 40.5 grains and 42 grains, and if the 42 grain load works as well as I think the 40.5 load will, then I will probably run with that, for the extra velocity alone.