Shooters World Powder: Long Rifle for 6.5 Creedmoor

[TexasTightwad]

This started out as a private conversation, but I decided to turn it into a thread.

"All I've done so far is load and shoot 50 rounds. They were loaded 10% below max charge. This was to get some once-fired brass so I could start load development (they say not to use new brass for load development if you are going to be neck sizing). Last night I loaded 14 rounds, 36gr to 39.9gr in .3gr increments, and I'm planning on shooting those after work today to find my rifle's "nodes". Then I'll load some in smaller increments to fine tune. I'll let you know what my final results are.

I've attached a picture of a target with 20 of those rounds fired at it from about 150 yards. I'm sure a lot of the spread can be blamed on me.

I'm using Peterson brass, which I highly reccommend. The quality is top tier, but they are half the price of manufacturers such as Lapua who have similar quality. I got the small rifle primer kind.

The bullet is Nosler Custom Competition 6.5 140gr. The meplats are pretty un-uniform, so that may have a small impact on my group size. I'm just getting into long range shooting, so I didn't want to pay for a top tier bullet when I am not yet a top-tier shooter.primers are CCI 400 small rifle."

 

[TexasTightwad]

"I looked at the picture and realized it is more than 20 rounds. Oh well.

I'll be starting to chronograph from here on out, so once I settle on a load, that should give a good indication of the powder's consistency.

It should be noted that, while all my brass, powder, and bullets will all be single lots, I will not be weight sorting anything. And while I am trickling for these tests, after that I will just be using a powder measure to throw charges. Ken of Shooter's World says that it is a waste of time to trickle to .01 grains because it has such a miniscule effect on accuracy, so unless you have eliminated all other sources of variance you should just use a powder measure. I figure he's right since he studies powder for a living."

 

[TexasTightwad]

I fired those 14 rounds from 200 yards yesterday, and here is a picture of the results.

The numbers represent the order of firing, starting from the lightest charge. Here are the corresponding charge weights:
1: 36.0
2: 36.3
3: 36.6
4: 36.9
5: 37.2
6: 37.5
7: 37.8
8: 38.1
9: 38.4
10: 38.7
11: 39.0
12: 39.3
13: 39.6
14: 39.9

I was surprised that there was no clear progression up the target with heavier charges. #12 has 9% more powder than #1, yet was about 2" lower.

The best sequential group was #s 4, 5, and 6, having a range of 36.9-37.5 grains. This looks like a probable node, and #s 13 and 14 don't look bad either, so I may also experiment with that range and above.

My hottest load was 39.9gr because the listed max is 40gr with Hornady brass which has slightly more volume, and the bullets are .003" from the rifling (if they started touching the rifling, pressure would increase). But I did not see signs of overpressure, so it is probably safe to go a little hotter.

I forgot to bring my chronograph this time. Hopefully next time I will remember, but I just have a ton of stuff to haul into the woods on my 4-wheeler for these tests!

P.S. #8 looks keyholed because it glanced off of support metal behind the target.