Most 348's have little to no throat, and will not handle my 250 LFN in standard profile. I reccomend that you choose a 220 gr, an as with all lever gun bullets, do not order a crimp groove. Seat bullet so they will function smoothly and the lever will close easily, then crimp lightly with a Lee Factory Crimp die. Or use compressed loads and no crimp, as the only function for crimping in a lever gun is to prefent bullets from being driven into the case when the stack of ctgs in the magazine slam back AFTER being jerked forward by recoil.
If you are dead set on a 250 gr, send a throat slug and I'll reduce the nose diameter far enough back so bullets don't have to be seated into the powder space. This option is getting a bit custom for me anymore, but I'll gladly do it to make customers happy.