Ladder test results

[JFrank]

That's the same for me. You could see it a lot clearly with AA4350.

Front bag and rear squeeze bag.

You really need a stable front support to gather good data.

 

[RegionRat]

You really need a stable front support to gather good data.

+1
The first and always the biggest mode shape is due to recoil.
The system of the gun and shooter must be as identical as possible during the shot process, or it just adds to the noise floor of your testing.

 

[Lead Slanger]

Okay, so after a long while and a whole lot of changing up everything (scope, some tweaking to the rifle, brass, bullets, reloading press, etc), I was able to go back out and do a little further testing.

Before, I was using Hornady brass and Hornady BTHP Match bullets while looking through a Sightron S-Tac 4-20. This last trip, I had some SRP Peterson brass loaded with H4350 and 140gr Berger VLD's, looking through an Athlon Ares ETR 4.5-30. What a difference all the way around.

I loaded up 30 rounds with 5 different charge weights. 15 rounds (3 shots at each charge weight) with a Remington BR primer and 15 with CCI 450 Magnum primers. I loaded 'em up starting at 41.7gr, stepping up .3, up to 42.9gr. I picked that range from a previous ladder test I shot. Right off the bat, I could tell the Berger bullets were a huge step in the right direction. The results, group wise, were what I was hoping to see according to the ladder test I had shot. The thing I really liked was, with the Bergers, my lowest charge weight had a higher velocity than my highest charge weight with the Hornady BTHP. 41.7gr loads were clocking 2745 and the 42.9gr load were clocking 2835 (26" barrel)

My best groups were with CCI primers and were at 41.7 and 42.9. Best groups were also at the same charge weights with the Remington primers as well, but were all around better with the CCI's.

Next trip I'm going to load up a few rounds around the 41.7 mark in increments of .1 and nail down my charge weight, then it's on to seating depth tests.