View Full Version : New developments. .22 in necked down .30 carbine spec rimfire

04-01-2011, 5:17 AM
Expected to have a standard weight of 50 gr. Testing shows cycles without issue in semi-auto rifles. achieves velocities ~2900 fps at 50 gr. out of a 16" barrel. 1:12 determined as optimum twist rate. Backed by 4 major companies for both ammo production and corresponding semi rifle production.

In your dreams :D

Tank 57
04-01-2011, 4:39 PM
And today's date is?

04-01-2011, 7:09 PM
Damn, I was all ears too.:(

04-01-2011, 7:37 PM
Here's a fun factoid...

In the 1960s-70s, some M-1 Carbines were caliber converted to 5.7x33mm (.22Spitfire).
It had a mini-resurgence in the 1980s, when a commerical manufacturer made some M-1 Carbines chambered in it.

The .22Spitfire (5.7x33mm) was .30Carbine necked down to .224 caliber, it launched a 50gr FMJ bullet @ 2700 FPS.

If you search the auction sites, you can still find some of the .22Spitfire M-1 Carbines for sale.
Like this IAI M-1 Carbine in .22Spitfire (5.7x33mm) currently on gunbroker (http://www.gunbroker.com/Auction/ViewItem.aspx?Item=220813794).

04-02-2011, 6:07 AM
wow. I just made the stuff up. One learns alot fast, participating on this site. Im guessing the main problem would be the limitations of a rimfire primer for such an amount of propellant.