Martini to .22 Magnum
I would not convert this rifle.
1. As already stated, the bore diameter is probably smaller. This would increase pressures. Although the Martini would probably handle this, it is quite possible that accuracy would suffer. After all, you want to hit something with it.
2. You would really decrease the value of a collectable rifle. Your rifle is probably worth more than the cost of buying a new rifle in .22 Mag. When you add in the cost of the reamer ( about $60-$80 ) and the labor to do the conversion, you are near the cost of a new .22 Magnum.
3. Reaming a chamber is not a matter of sticking the reamer in the barrel and turning it. You could easily ring the chamber or ruin the barrel if you don't have the proper equipment or skills.
4. The cartridge may be too long for good feeding in the Martini. It may stick and jam because of the sloped loading ramp on the breech block.
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