243 AC

[mpolk]

Looking at a Mauser action marked 243AC. Ackley Improved would be AI. Any idea what that caliber is?

 

[JD0x0]

I have no idea. I would've assumed it meant "Ackley Chambered"

 

[Brian Pfleuger]

I would guess it means "Ac"kley but I wouldn't assume it.

I've seen the abbreviation AC Improved before and could only think it meant Ackley.

You could try chambering a .243Win. It should "crush fit" if the rifle is an AI and correctly headspaced. That's be an additional clue.

Otherwise, a gunsmith and/or chamber cast is in order.

 

[mpolk]

That's where I'm at. Thanks for the reply