Working with the 6.5 Creedmoor

[wildcat westerner]

When the 6.5 Creedmoor came out years ago, I already had a better cartridge. The Creedmoor originally used Hornady brass and a large rifle primer. I had discovered the 6.5 IHMSA and in using Palma Lapua .308 brass, it already had a small primer. I had to laboriously cut a tenth off the case and then neck it down, but it was a good cartridge. Someone stole my brass off my bench at the range, probably thinking it was Creedmoor. Since the original brass had lasted all these years, except for occasionally neck annealing, the easiest route for me to go was to have that bartlein barrel rechambered to the 6.5 Creedmoor and get some Lapua, small primer brass.

Working with this cartridge less than a month, I am astounded as to how much performance gain has been achieved. Using 142 grain MatchKings the older cartridge gave me 2,550 fps. The new CM case gives me 2,800+, which seemingly violates physics for such a small increase in powder charges. With my Stolle action, with its bushed bolt, I am finding that 43 grains of IMR 4350 gives me less than 1/2 minute groups at 7-800 yards today and quite frankly this barrel was not that accurate before. The load pressures allow easy bolt opening and extraction and the primer pockets seem as tight as they were when I first loaded them. All this seems near impossible to me . I know according to loading manuals I am way over max for such a small case, but the accuracy, at exactly -.003 leaving me with the impression that the limitation on this rifle is mainly me, after this mornings' session.
Are other shooters, pushing the 6.5 Creedmoor experiencing such results?

 

[bergara0256]

I was wondering if they use a reamer with more freebore allowing you to push the cartridge more? I've only be able to get mine to shoot 39.5 grains of IMR 4350 and getting 2,550FPS.

I am shooting a factory rifle and not a custom though in the 6.5 creedmore.

 

[Roughrice]

I have a 28" Criterion Rem/age 6.5Creedmoor barrel that pushes 140 grain out at 2830-2850 fps with 42 grains of H4350.
It punches way above it's design in that configuration.

 

[243winxb]

https://bulletin.accurateshooter.com/2020/01/6-5-creedmoor-load-data-charts-from-sierra-bullets/Over by 7/10 th grs. This could be the difference between powder lots?

Brass makes a difference also, as you know.

 

[wildcat westerner]

Thanks guys, I have consulted with someone I trust implicitly in this matter and he concurs, I am just "pushing the envelop" a little bit, not a lot that would cause concern. As mentioned my Stolle action has a bolt that has been bushed, and my barrel is 25 3/4" long due to the setback in rechambering. All in all, this situation has turned out so positive after years of mediocrity, in terms of velocity advantage increase between two very similar cartridges. Since I have been reloading since the "sixties, to see such a velocity increase from such a small case expansion. still seems amazing to me. Apparently the 6.5 CM case design volume was created to be a perfect place for the 4350 powders, I have a large amount of IMR 4350 and all of it will be going down this rifle barrel.

Thanks again,

WW

 

[hesse]

I went with a 24 inch barrel the little woman's gun I picked up189 fps using the same load . She wanted a fluted barrel so that is what she got she don't ask for much so she got it