Has anyone heard of, or had experience, with this chambering? I'm told that it is based on the 220 Russian or a version of the 5.56x39 wildcat.

Yep is was a mid 60s Rambler. Sorry haven't heard of a chambering.

I've never heard of it either. If it exists, I would think CH4D would list it. They don't, and they also don't show a 5.56x39

I'm building a mini mauser in 220 Beggs. It is basically a 220 Russian with a different radius at the neck shoulder junction. The regular 220 Russian is great, but the brass grows in the neck area and needs constant trimming. The 220 Beggs gets around this. Hornady has dies and PT&G has the reamer. If you do the blown out Ackley version you will have the 22PPC.

The rifle in question came from a friend who purchased it from a talented local smith who is no longer with us. He chamber stamped the barrel 5.56x39 but referred to it as a "220 American". Lapua made ammo and brass headstamped 5.6x39 (later changed to 220 Russian) and Sako did the same but used 220 Russian for their stamp. Bullet diameter for the 220 Russian was (is ?) .221".
I've made a chamber cast and also have a dummy round. As near as I can tell, the so called 220 American is a tight necked 220 Russian that uses .224" bullets.

220 Russian: http://www.6mmbr.com/compcartridges.html

The 220 Russian for the last many years have been the standard 224. It makes no difference if you have the proper bullet for you barrel.

quote:

Originally posted by butchlambert:
The 220 Russian for the last many years have been the standard 224. It makes no difference if you have the proper bullet for you barrel.

Thanks, but I realize that.

I don't know what you realize, but some do not. Do I need to delete my post?

No, not all. That's why I said thanks.

I certainly wasn't trying to say your info was bad or trying to make you look bad. Oh! the internet.

No issues on my end.