I just built a 6mmx222 this year on a left handed mini Mauser. It wears a 24 inch #1 contour PacNor barrel and an MPI stock. My initial load testing so far has been limited to the Speer 1211 80 grain spitzer. The load I currently am working with uses BL-C2 and churns up 2608 fps. Not a barn burner but very accurate.
I'll be doing considerable more load development this winter and have 200 rounds of brand new Sako brass with which to do my serious load development work.
I brought the rifle with me down to eastern Washington to hopefully try it out on some coyotes. Forty stands later and no coyote response it remains unblooded. I guess I'll have to get after the fox and lynx when I get home.
It is a delightful round to shoot. My rifle weighs about 5 3/4 pounds and is an joy to carry and recoil is essentially non existent. I built with that in mind, as a light weight calling/stalking rifle with enough power for an occasional wolf. At the same time with mid range bullet weights at moderate velocity it should be pretty gentle on fur, even the more delicate fox and lynx. I had hoped a few coyotes would offer themselves up in the interest of bullet performance testing. It wasn't to be.
Fadala reported getting up to 27 grains of BL-C2 in his cases with an 80 grain bullet. I don't see how he did it. I've checked several brand of brass and cannot get that much powder in any of them. Perhaps the cases he was using had a little more capacity. I believe he used Speer cases in his load development and they are not available anymore.
It has been a fun little round to work with. I have data from Hodgdon and from Fadala's article. I've posted a fair amount about it on the 24HCF and AR forums. I opted for the 6mmx222 over the 6x45 and 6x47 because the mini Mauser magazine is not well suited for either of those. The box is a bit short and OAL is limited to 2.226 for reliable functioning. That means the bullets are seated very deep in the case on the 45 and 47 cases. Here's a few pics.
This is the action in the white with a 6mmx222 dummy round. A good fit.
Here's a line up for comparison. 6mmx222 loaded to fit the magazine, 6x45 to the same length, 6x45 seated to the base of the neck, 6x47 seated to the base of the neck, 25x222, 25x45 and 25x47, 6.5x222 and 6.5x45.
