Reaming an AI chamber by hand

[CApighunter]

I’ve been looking to pick up a cheap savage take off barrel to put on my Origin action with a barrel nut and was thinking of getting a 243 barrel and reaming it to 243AI by hand. The shoulder/neck datum line is .004 shorter on the Ackley which would hypothetically make the chamber longer than spec but if I headspace with a barrel nut wouldn’t I be able to take up that extra .004 by setting the barrel a smidge deeper? Same idea as setting back a thread on a shouldered barrel. As long as there is sufficient clearance between the bolt nose and barrel breach face it should work in theory. Anyone tried it or have any thoughts if it’ll work?

 

[2muchhp]

It should work, one beauty of a barrel nut. Back in the 80s my dad I reamed a 280rem to 280rcbs and a 30-30 win to Al.
The 30-30 is long gone but he handed down the 280rcbs a couple yeas ago

 

[nksmfamjp]

I would put the barrel on and see how many rotations from touching the bolt head until the GO gage fits. Actually, I think I would thread It until it stops on the GO gage, mark the barrel and action, then thread it on more w/o the gage until the bolt head stops it. Then pull out some Trig to figure out the axial pitch between the 2 points. There will be some slop, but should be close enough.

 

[CApighunter]

I would put the barrel on and see how many rotations from touching the bolt head until the GO gage fits. Actually, I think I would thread It until it stops on the GO gage, mark the barrel and action, then thread it on more w/o the gage until the bolt head stops it. Then pull out some Trig to figure out the axial pitch between the 2 points. There will be some slop, but should be close enough.

20 TPI is .050 of travel per full rotation so I’d need a little less than a 1/10th (28.8 degrees) turn past to set it back to spec. It might just work… worst case a regular 243 is no slouch.

 

[Newtosavage]

Interesting discussion. I might have to try this with the 7mm-08 barrel on my Savage LWS.

I never use factory ammo anyway (but still could in a pinch) so I don't really see the down side.

 

[CApighunter]

Interesting discussion. I might have to try this with the 7mm-08 barrel on my Savage LWS.

I never use factory ammo anyway (but still could in a pinch) so I don't really see the down side.

AI everything! If it works I may also try it with a 223 barrel for a centerfire trainer. I’m really curious what a 69gr absolute hammer would do out of a 20 inch 243AI….

 

[Cahunter805]

It should work if you have clearance like you stated. Not to be a downer but the 243AI is probably one of the least improved cases when going to AI. I do get the rifle looney aspect and if it’s what you want there’s nothing wrong with it. I had one and for all the extra work and components It wasn’t much of a gain and sold it. Instead I built a properly setup 243 and have been happy with it.

 

[Newtosavage]

Even if it just keeps me from trimming brass as often, that would almost be enough for me to consider it. Trimming brass is my least favorite part of reloading. LOL