Gunsmithing AI headspace question

[Sixfivesavage]

Quick question since I can't seem to find a definitive answer. Can I headspace a new .243 AI barrel on a savage with a .243 case? Haven't been able to find a go guage in stock anywhere.

 

[wtopace]

Yes, the bolt should be a "nice snug fit" to close, but don't set it so you require a hulk smash to close it.

 

[Killswitch Engage]

308, 7-08, 260 and 243 et al are same head space gauge just so you know

 

[Sixfivesavage]

308, 7-08, 260 and 243 et al are same head space gauge just so you know

I am aware, just wondering if I could use the parent to headspace the AI as far as a FL sized case goes.

 

[DAVETOOLEY]

You can't use a standard gage to headspace a case with a 40 degree shoulder. The datum line for a standard case is located on the shoulder and never changes regardless of caliber. Using a standard gage in an AI chamber moves that datum line to the junction of the shoulder and neck. That varies greatly with caliber. In a pinch you could use a piece of virgin brass. Very lightly touch the neck shoulder junction.