Gunsmithing Rechambering 6.5cm to 260 ai

[jcmullis2]

I just picked up a good deal on a new prefit 6.5cm barrel for my tenacity and need to know if it could be rechambered to a 260 ai without re cutting the tennon and rethreading the barrel. I already have a couple of 6.5cm and I’ve heard good things about the 260ai. Thanks

 

[gnochi]

It looks like it *should* clean out the chamber, but it’ll be damn close depending on the exact reamer used for each. I’d need to boot up my cad software to do an MMC/LMC fit check. It’s the weekend, so I’m somewhat less than inclined to do so lol

 

[Ledzep]

I can't find a .260AI print. The biggest thing you have to watch out for is the shoulder diameter of the 6.5 Creedmoor being bigger than the shoulder/body diameter of the .260AI at the same place. You'll get a funky little ring in your cases that will work harden over time and give you a case separation sooner than you'd expect. May/may not cause extraction issues, too.

 

[Terry Cross]

Ledzep

 

[Ledzep]

Yeah it's not going to be much, but assuming perfect min-spec dimensions all around there would be just a ghosting of the shoulder/body on the Creed left over. By the math at the 6.5's body/shoulder junction (.462"), the .260AI reamer would be .4611", so in a perfect world a little under a half-thou deep leftover bit that would taper down to the same body diameter at the base. Can't tell you exactly what that'd look like in the real world. Might could work. Worst case you have to set things back a hair.

 

[DAVETOOLEY]

Then there is matching neck diameters. I've got a 260 AI reamer. I need to look at the print.