[Rapier]

The thread did come up before, and the same data is repeated. The data is in error, one more time.

The 310 bore diameter is larger than the diameter of the 32-20 bullet, so to rechamber a 310 Martini to 32-20 is not the correct way to go.

The 225 winchester is the largest diameter and and highest pressure round that the cadet action can be chambered for. The 225 case head is .422, same as the 30-30 and its brothers, like the 32 Win, the 225 pressure is 65K, the 225 case body is .090 longer than the 30-30. I built and own a 225 cadet.

The cadet can be chambered for 30-30 and it will work just fine. THe 30-30 has a short body, is tapered and bottlenecked.

The proper diameter / rechamber candidate for a 310 Martini barrel is the 32 Win Spl. However the BP twist of the 310 is not the same as the Winchester twist rate and the bullet selection is sparce.

For an Aussie, I would reccomend for you, a 222R or similar down under round. You might also consider a 7.62x39 in a 308 barrel and use 30 cal dies. The 308x39 is close to the 30 Harrett and is a fine round in a short barrel.

I own and build custom cadets. With a good barrel, and a trigger job, a custom cadet will shoot half inch groups at 100 meters. My 222R and my 225 will shoot .5 inch groups. My two 357 SM guns will shoot .50 inch groups. My 218 Bee does about .75 but it has a rimfire barrel and the barrel is not what I will keep if I rebarrel the gun at a later date. I sold another 218 Bee and a 310 original, which I shot with converted 32-20 brass that I built dies for.

The admonition about the firing pin bushing if for real. I would add that the pin itself, normally protrudes a bit to far and may need to be reduced in length and slightly in diameter, to prevent pierced primers or primer cratering / blow back. I normaly also replace the firing pin spring with a heavy spring. Also, for best accuracy, attach the forearm with two screws, front and back, then glass bed the forearm for 100% contact. Make sure the forearm does not touch the action. I use the case head of the chamering as the two eschutions. Old saying, either float the barrel or bed it. You can not float a cadet barrel, so.
Ed