As far as I can tell, here are the options for putting the caliber on a newly-installed barrel on a bolt gun (or otherwise):
1.) Use a hammer and letter/number stamps to stamp it in with impact
2.) Buy a "new hermes" type engraver and engrave it on yourself
3.) Take it to an engraver/jeweler and have them do it for you
4.) Use a CNC mill
5.) Electro-chemical-etching options
#1 isn't the most modern, neat way to do it. It's too easy to get the letters crooked, and the alignment jigs seem to...
Stamping/engraving Caliber On Rifle Barrel
1.) Use a hammer and letter/number stamps to stamp it in with impact
2.) Buy a "new hermes" type engraver and engrave it on yourself
3.) Take it to an engraver/jeweler and have them do it for you
4.) Use a CNC mill
5.) Electro-chemical-etching options
#1 isn't the most modern, neat way to do it. It's too easy to get the letters crooked, and the alignment jigs seem to...
Stamping/engraving Caliber On Rifle Barrel