This is what I have read many times. Worries me. I wish somebody with an XC would chime in.
Paul
I had a 6XC before the better brass they have now. I built it for 600 yds benchrest, I wanted more speed over the 6BR. I did not get the speed or accuracy, 3" was the best it would do at 600yds, it is good for most shooting, but not for 600yds benchrest.
When the 6.5x47 came out a lot of guys built a 6mm X 47, and could not get them to shoot also. They cut the chamber off and rechambered to 6 BR, 6BRX and 6 Dasher and they shot good.
I think the brass was my problem with 6XC. I think with the new brass the 6XC would be good.
The problem with the 6x47 is the small primer and small flash hole, guys that got it to shoot better were opening the flash up, and it shot better. It works great for the 6.5mm, but not as well for the 6mm.
Remember the accuracy I am talking about is 600 yds benchrest, it takes sub 2" aggs to win now. But 3" = 0.5 MOA, that would be great for hunting or steel shooting.
I have heard a lot of guys are necking the 6.5 Creedmoor to 6mm
All my guns now are 6 BR or 6 BRX. I guess you want a mag feed gun, the 6BR type's don't feed to good from a mag. But accuracy is the best. The 6BRX or 6 Dasher would give you the same speed in a 18" as the 2 you are looking at, and much more accuracy. They work great in short barrels.
Mark Schronce