I have been building a Martini Cadet over the past six months or so and shot it the first time today. The cartridge is formed from the .357 Rem Maximum. I used a take off barrel chambered for the .223 Rem. Loosing the cartridge length That had fit into the original bolt nose plus the rim recess I cut into the barrel left a chamber just 126 thousandth shorter than the original .223. So I have a rimmed round 1.312" from the base to the bottom of the shoulder. I will have the barrel engraved .224 Belding after the intended use (Belding ground squirrels) if this has not been done before and already named. Anybody know?

If there isn't another version out there, I like .224 Belding. Quite appropriate. But more important than the name, how does it shoot?

Have you considered using 222 rem dies to form? Set the barrel back and ream with 222 reamer. Use 222 ammo or the rimmed with Maximum brass with a short neck.
How about the 222 Maximum as a name?

I did a 17x357 Max. for a customer on a TC Contender. He thinks brass quality is the limiting factor but I have never been over impressed with the accuracy potential of TC barrels. It shoots well enough for GH's.

Working up brass for this thing was a PITA, but I have about 250 cases ready so the chamber and case are staying as is. For the first trial I loaded up 15 rounds with 25 grains of H335 and a 50 grain Sierra Blitz. Getting centered at 40 meters then 100 yards used up 9 rounds. The last six went into an inch, with 5 of them under five eighths, so I am like the GICO commercial, happier than a witch in a broom factory.

Nice project. What kind of velocity are you getting ? roger

It's called the 224 GNR



http://www.reedercustomguns.co...n/GNR_cartridges.htm

Thanks Smokin Joe, that's got to be real close. Since I am not sure of the actual dimensions, I think I will just not mark my barrel. It's not going any where any way.

bartsche, I did not set up the chrono for this first trial, but I will be working on load development this week and will post data.

roger

Some velocity data as promised follows. This is with a barrel length of 21 inches,temperature thirty degrees, altitude 3500 feet. 23 grains of H335 yielded an average (all 5 shot strings)of 2974 fps. 24 grains of H335 yielded 3076 fps, and 25 grains H335 (too hot, sticky extraction) gave 3143 fps.