My first .264 was back in the 70's. It blew up a bunch of groundhogs for me, but I had to let it cool for 1/2 hour after every 3 or 4 shots. My 6.5 Rem. Mag did almost as well, gave very similar speeds to the 22" .264 mag., was more accurate & used less powder.

In the mid 80's, I rechambered a 6.5x55 to .6.5x68 on a new M96 Swede. Brand new barrel. Yes I know it can't be done - it's toolong, too much presssure adnausium. According to Ackley, a certain Dr. Arch did a .264WinMag and so I did a 6.5x68. I kept my loads 100fps lighter than my buddy's P14, so only went to 82gr.(or something like that) H870 with 129 Hornady's for 3,200fps. He was getting 3,300fps with them.

It shot splendidly, and I once blew up 2 snowshoe hares at 210 & 220 yards (10 yds. apart, in line) with one shot.

Since these two ctg. are ballistic peas in a pod (normal 12" twist for the 68mm, 9" for the .264) wht can be said for one equals the other. I spotted for Keith once, on a bull elk - 275 yards, bullet 129gr. Hornady, 3,300fps MV. At the shot, red spray blew out the entrance hole and exit hole at the same time, perfect broadside shot, 1/2 way up the beast's rib cage for a moderately high lung shot.

Pretty good performance for a 'soft' bullet. He had to use the 129's as heavier bullets were too long for the rifling twist. He's since gone to 9" for his 6.5 X 68's.

The big cased 6.5's good, but go through a barrel a bit fast for someone who shoots a lot.

A 6.5 with 57mm length case with 60gr. capacity will about duplicate their peformance and last at least twice as long.