Rechamber 6.5 Creedmore to .260 AI

I didn't notice the shoulder diameter difference of .462" for the creed vs .459" for the AI. That will likely require too deep of a hole to eliminate that diameter on a light weight sporter contour barrel.

Thanks for pointing that out.

A new barrel is probably the best option.

Interesting that the Creedmore has so little body taper and is considered great, but AI cases are criticized for that feature.
 
Vincemule

This was an idea. I hadn't bought the creedmore rifle yet. It looked like an inexpensive way to get my son a deer rifle. Creedmores are a plentiful and cheap, but I don't load for them. I do load for .260 and .260 AI.
Do you have an action that you could build a 260/ 260 AI? I'm happy with my 260AI. I hit 2860 fps pretty easily with 145gr Barnes Match Burners.
 
Vincemule

This was an idea. I hadn't bought the creedmore rifle yet. It looked like an inexpensive way to get my son a deer rifle. Creedmores are a plentiful and cheap, but I don't load for them. I do load for .260 and .260 AI.
You want cheap, black Friday a savage rifle package and buy a Criterion prefit from Northland Shooter Supply. They have 260 AI. I will say this about the creedmoor, I broke down and bought a barrel and dies, used some old lapua 260 brass to make the initial loads. I have 3 260 rems, and the creedmoor did not win me over. I'm not sure why the fan boy following, but to each their own.
 
I didn't notice the shoulder diameter difference of .462" for the creed vs .459" for the AI. That will likely require too deep of a hole to eliminate that diameter on a light weight sporter contour barrel.

Thanks for pointing that out.

A new barrel is probably the best option.

Interesting that the Creedmore has so little body taper and is considered great, but AI cases are criticized for that feature.
But...those dimensions are at different distances from the bolt face. 6.5CM .4620" is at 1.4900" from the bolt face. .460" for the 260AI is at 1.6703" from the bolt face. At 1.4900", the .260AI is .4622".
 
Lance

Are saying it could work?
It could, depending on how close, to true size, the original chamber was cut. If I were going to give it a whirl, I'd set the barrel back the length of the neck (.295-.300), then rechamber. You'd probably be better off just starting with a fresh barrel though.
 
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According to the chamber prints the 6.5 Creedmore is .4709" at the widest point on the case body. The .260 AI is .4714" at the widest point on the case body.

Question, is .005" enough material to keep a reamer centered when rechambering a mass production 6.5 barrel to a .260 AI?

Would setting it back a few threads increase the margin if the factory tolerances are too sloppy?
Not .005, its much smaller .0005"
 
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Lance

Are saying it could work?
I am saying "maybe". Depends on which .260AI reamer you get. Since the .260AI or .260 Rem Imp 40° is not a SAAMI approved print, there are a lot of variations you could find. One of the big differences is FB between the .260 Rem, .260AI, and 6.5CM. My reamer has an additional .090" FB over the standard .050" for a total of .140". Specifically to get the 140 Hyb or 140 Elite out to max mag length.

I am also saying, for a cheap factory barrel, I think I would just shoot the 6.5CM it came chambered in. If I was going to invest in a rechamber, I would bite the bullet and but a new high quality barrel blank for the best chances of an Accurate rifle.
 
Vincemule

This was an idea. I hadn't bought the creedmore rifle yet. It looked like an inexpensive way to get my son a deer rifle. Creedmores are a plentiful and cheap, but I don't load for them. I do load for .260 and .260 AI.
Do you reload for 243 win? And again do you have any actions available to rebarrel?
 
Your cutting it close with just .005 . That's just .0025 per side for a reamer . From a machinist perspective it's only do able if everything is perfect . The run out of the barrel will need to be zero to the bore dia and the reamer must be centered perfect. Usually we run reamer at .005 per side or .01 under . I'm a aerospace machinist not a gunsmith but it's the same principles.
Just re read the tolerance and .0005 is not enough stock . It definitely depends on the depth of the rest of the chamber cuts . We've run into chatter issues with step reamers having issues with not enough to prevent chatter as the first dia is usually the support for the rest of the cut.
 
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