I'm just curious because I've been looking at the 7.62 x 54 r cartridge and a 308 cartridge both shot and there maybe a millimeter of a difference in size would it be possible to convert a let's say mosin nagant from a 7.62 x 54 r to a 308 caliber rifle. Or even shoot a 308 in a mosin nagant.
I am not a gunsmith and I'm not going to do that. I'm just curious in a last resort could you shoot a 308 in a 7.6 x54r
It would need to be rebarreled. The x54r chamber is much larger than a 308. While you can easily, relatively, ream out a smaller chamber for a larger cartridge using the same size bullet its much harder to reliably add metal back.
There are chamber inserts that allow makeshift downsize conversions they arent that efficient and generally much more pita than a barrel swap.
If you want to use308 bullets in a mosin rebarrel it with a 308 barrel and ream it to fit the headspace and just reload using x54r brass and 308 bullets.
X54r has much more case capacity than 308 its almost identical to 30-06
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