Martini cadet .310

[muzzle flash]

Just recieved a very nice cadet. I am new to these rifles and am looking for some info. I have read you can use 32/20 brass that is trimmned. I am able to chamber a untrimmned 32/20 brass with no trouble. I have not made a chamber cast. And am wondering if you should be able to chamber a untrimned 32/20 brass in a unaltered cadet. I was able to seat a 150 gr. .323 jacketed projectile and shoot it out. The fired slug measured at .3175" Basically I am wondering if I have recieved one of the cadets that have been chambered to 32/20. Am trying to avoid having to pay for a chamber cast preformned.
THANKS.

[Reg]

First, to really know what you have, do a chamber cast. Just do it yourself, they are a no brainier.
Take the action down and clean it along with the bore. Lightly oil the bore and put in a cleaning patch plug about one inch or just a bit less up into the refiling just in front of the chamber. Support the receiver and barrel vertical in a padded vise. Do not attempt to hold it in your hands.
Bend up a small metal can into a long pointed snout, put some kind of handle on it and make sure the snout will reach into the open area of the chamber. Get some sulfur. In pharmacy's they call it flowers of sulfur, same stuff. Put about a inch or so of it in the bottom of the can and carefully set it over a very low heat. A small electric hot plate works well. Do not over heat. Hold it over the fire until it melts, will look like a clearish yellow liquid. Carefully pour it into the chamber, let set for just a second or two then top off with another tiny amount. It tends to shrink. Once it stops shrinking let set for a couple of minutes, loosen vice swing the action horizontal and using a piece of 1/4" drill rod or a brass rod, push out the casting. Be careful, if you drop it you most likely will break it. It's very brittle. It might take a couple of taps with a leather mallet to get things moving. The oil should keep anything from sticking.
If your wife is fussy, you might have to do this outdoors, it kinda smells a bit. Do not get ANY of the molten sulfur on you, the resulting burn WILL scar.
With this casting you can determine what kind of chamber you have. Many of these neat little rifles were reamed from the .310x18x120 to the 32-20, most were marked, a few were not. A few that were not reamed will accept a 32-20 round and if so, great, just fire form and go for it.
The stub of the casting that went up into the rifling will tell you bore diameter.

;)

[calaloo]

If you do a chamber cast be aware that if you include too much of the bore ahead of the chamber you might no be able to remove the cast. Just be sure that the length is less than the distance from the end of the barrel and the rear of the frame. some unmodified chambers will accept the .32-20 round but the bullet is too small for the bore. Get the proper mould and you are in business.

[SOFMatchstaff]

I had to make up some brass for a friends 310 Cadet, the rim thickness is the deal killer. If you can chamber an un-altered 32-20 in your rifle, the odds are very good that it has been chambered for the longer round. the 32-20 rim is thicker by .020 or so, .065 vs .043. case length is considerably longer also 1.120 vs 1.300 plus or minus. If the chambered round is flush with the breech and the bolt rotated up smoothly, I'd say you are good to go. Take a 32-20 case and Bell it out to what looks excessive and push it in the camber and see if it hits a Hard stop about .200 short of a fully chambered case, if it does then you might consider a chamber cast to prove the measurements.

I loaded the finished brass with a 90gr Hornady 32 cal (.314) soft lead HBWC, #10028. I also used a Berrys plated 32 HBWC, and both shot very well in the Cadet. I started out with loads for the 32S&W Long and worked up to a good accuracy load. It takes a bit to get the HBWC to upset and shoot consistently.