Everyone has there own opinion and procedure for barrel break-in I will tell you what has worked the best for me after several years of setting up and breaking in new guns for myself and several others.
1. I always completely disassemble and thoroughly clean ANY new gun no matter what inside and out. New guns are sent full of excess oil, grease, cosmoline etc. This is where most shooters get into trouble they pick up there new gun throw rings and a scope on and go shoot BAD MISTAKE!
2. Having the right tools saves alot of time and makes things alot easier
good cleaning rod
correct jags and brushes
solvent and oil
bore guide I wouldn’t even consider putting a rod or anything down the barrel of 1 of my rifles without one.
3. For 10 shots clean after every shot, then shoot 5 3 shot strings clean after all 5, then shoot 5 5 shot strings
cleaning after each 5. I know this is 50 rounds but it is worth it to break in you new investment correctly.
This has worked well for us on alot of rifles of numerous manufacturers.
Always use a good solvent then patch dry then add a little oil your barrel will last and this will get the most accuracy out of your barrel. Good Luck and Good Shooting!!