Thoughts on where to go from this load test?

[Nik S]

Not very experienced with load testing, and could use some guidance on what to try next.

Posting somewhat dubious results on my first load test for 6.5 Creedmoor at 100yds. Should I pick one of these and play with seating depth?

Shooting Tikka CTR 20" barrel, 6.5 Creedmoor
IMR 4451
Federal large rifle primers
Lapua 139 Scenar-L
COL: 2.7. I could comfortably go to 2.8 and still fit in my mag.
The target crosses are 2"x2"
4 shot groups
No chrono

 

[nn8734]

40.1-40.7 looks like a somewhat stable node insofar as group center POI is concerned. I’d try to develop 40.4 and see what seating depth trials yield. Also take your chrono to see how fast they are going if you have a minimum muzzle velocity you are trying to achieve.

 

[jakelly]

The word around here is that it’s all noise, pick any one of them, tune seating depth, and drive on. If you can’t get what you need switch powders.

 

[bluejay75]

There’s a million right answers here but here’s my take. I shoot that bullet in 6.5 CM, why did you go that short? Start at mag length and you will still be 30-40 thousandths off the lands. I shoot it at 2.815 in my Savage.
You didn’t go high enough to get to the high node. You’re 2-3 grains off max depending on who’s data you use. With a 20 inch barrel you’re already giving up quite a bit of speed, my guess is that you topped out at a little over 2400 FPS. I would shoot from 40 up to where the gun tells me max is. Maybe up to 43.6-44.

 

[Nik S]

I shoot that bullet in 6.5 CM, why did you go that short?

Dumb aesthetics and an over-developed need to reinvent the wheel. I've shot mostly .308 and 300WM. 6.5CM seems awfully long in the nose. Cyrano long.

I thought, maybe if I just push the 6.5 down a little...

Thank you to these responses. I'll experiment with seat depth at 40.4, and also experiment with some higher gr loads at 2.8 COL.

Nik

 

[acudaowner]

the only imr 4451 load I had any luck with so far using 1.5 thou for a neck tension was 42.0 got me a max: 2737 min 2719 avg of 2729 sd: 9.3 and an es: 18 hoping that will improve slightly with a looser neck maybe maybe not .
I have to try them again with a .5 neck tension I am using a 26'' barrel there were others that shot nice but the numbers I got were not so nice like 42.3 that got me an avg: 2743 which is more like what I am looking for speed wise it also shot nice but the sd's and es's were worse than a factory load good luck with finding something to work for you . I only went up to 42.4 as I don't need anything faster than the 2772 it gave me for the range I am shooting at . I like the round as I was able to get enough stuff to reload it for a while & I can keep my loads to my goal of 42.0 and under with a lot of different powders and achieve my speed goals + I had the brass so why not it's good hell almost feels like cheating at 1k which is the longest range I have in my area hitting a clay at 900 was easy enough a child could have done it and now at 6,450 rounds its still shooting really well even though I was told that 1500 - 2500 rounds was about all it would get through the barrel they were wrong so very wrong lol I also love the 308 and 3006 they are great rounds as are so many others use what you got and enjoy the hell out of it. best of luck.

 

[Doom]

The word around here is that it’s all noise, pick any one of them, tune seating depth, and drive on. If you can’t get what you need switch powders.

Pick a seating depth and adjust powder charge or pick a powder charge and adjust seating depth. You can end up with the same result.

As for the OP’s test, I would pick 40.4 and work with that.

 

[Nik S]

moved thread.