.310 Martini Cadet
Back in the good old days of the 1960s, they were freely available in a lot of surplus stores in Canada. I can remember a barrel full of them, for $9.95 and take your pick. I think they were BSA, Greener, and Wesley-Richards makes.
As no ammo was available, we used .32 Smith and Wesson Long cartridges with fair accuracy. It blew out the casing slightly, but they fired and ejected without any problems.
A lot were rebarreled for .38 Special / .357 Magnum, 30-30 Winchester, .32 Winchester Special, and other cartridges. The actions made a lot of varmint rifles too, in .22 Hornet and .218 Bee, with the extractors being modified.
I did not have access to .222 rimmed Cartridges as in Australia, but I made one up for the .222, and used "C" clips slipped into the extractor groove of the case so that they would eject. Worked well, and later when I had access to a machine shop, I made a spring loaded extractor and reset the barrel back so that I could use standard cartridges. I shot a lot of Southern Ontario Woodchucks with it.
The present price for one in Canada, if you can find them, seems to be about $400.
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