I don't think a little Martini is much good at forcing a case into a chamber, a High or Low wall yes.
I once had a gunsmith take the barrel off one of my Martini's in 222 to fit a silencer and the cases I had neck sized just wouldn't go in after he had refitted the barrel.
I think he had tightened the barrel down just that little bit more than when it was originally fitted altering the head space and I had to pull all the bullets on the cases I had loaded, set the die down just the slightest fraction to push the shoulder back.
Regards.