Prefit Barrel Question

hhunter318 · April 19, 2012, 02:20 PM

I might have beat this to death, but I've decided on the 7x57 Ackley Improved. I know I'm going to get asked why go with an AI, but the answer is just because, and they're a little more unique. My question is can you take a barrel prefit to 7mm-08 and run the 7x57 Ackley Improved finish reamer in to headspace correctly to make this work? I know you'd have to set the barrel back to correctly chamber it if its already chambered to 7x57, or am I wrong?

Thanks for any responses.

hhunter318

**James K** · April 20, 2012, 12:44 AM

A 7mm AI reamer should clean up either a 7mm-08 or a 7x57 chamber.

It should not be necessary to set back a 7x57 barrel unless the headspace is already excessive.

Jim

hhunter318 · April 20, 2012, 03:35 PM

Thanks for the info. When I was told the barrel would have to be set back for the 7x57 to 7x57AI, I couldn't understand why since only the shoulder angle and body taper are changed and not the length of the neck. Again, thanks for the answer.

**James K** · April 21, 2012, 08:58 PM

The whole idea of the AI cartridges, per Ackley himself, was to allow a standard chamber (7x57 in this case) to be reamed out and the standard cases fire-formed to create the AI brass. No barrel setback required.

Jim

April 19, 2012, 02:20 PM	#1
hhunter318 Senior Member Join Date: September 15, 2010 Posts: 142	Prefit Barrel Question I might have beat this to death, but I've decided on the 7x57 Ackley Improved. I know I'm going to get asked why go with an AI, but the answer is just because, and they're a little more unique. My question is can you take a barrel prefit to 7mm-08 and run the 7x57 Ackley Improved finish reamer in to headspace correctly to make this work? I know you'd have to set the barrel back to correctly chamber it if its already chambered to 7x57, or am I wrong? Thanks for any responses. hhunter318

April 20, 2012, 12:44 AM	#2
James K Staff Join Date: March 17, 1999 Posts: 16,424	A 7mm AI reamer should clean up either a 7mm-08 or a 7x57 chamber. It should not be necessary to set back a 7x57 barrel unless the headspace is already excessive. Jim __________________ Jim K

April 21, 2012, 08:58 PM	#4
James K Staff Join Date: March 17, 1999 Posts: 16,424	The whole idea of the AI cartridges, per Ackley himself, was to allow a standard chamber (7x57 in this case) to be reamed out and the standard cases fire-formed to create the AI brass. No barrel setback required. Jim __________________ Jim K

April 20, 2012, 03:35 PM	#3
hhunter318 Senior Member Join Date: September 15, 2010 Posts: 142	Thanks for the info. When I was told the barrel would have to be set back for the 7x57 to 7x57AI, I couldn't understand why since only the shoulder angle and body taper are changed and not the length of the neck. Again, thanks for the answer.