From the Pac Nor home page Barrel Care....
Do's and Don'ts of Barrel Cleaning
Do's:
Use a good coated rod
Use a bore guide
Clean from chamber end (whenever possible)
Use a bronze bristle brush
Follow recommended break-in procedures (listed below)
Don'ts:
Use a stainless bore brush
Leave strong ammonia cleaning products in your bore for extended periods of time
Shoot your barrel hot enough to brand cattle!
In our experience, the loss of accuracy can be linked to a dirty or fouled barrel approximately 98% of the time!
Barrel Break-In and Cleaning Techniques
Thanks for purchasing a barrel from us!
For best results, of course, it is necessary to 'season' it and use proper cleaning equipment. We like the Dewey coated rods, a good bore guide, copper/bronze brushes and cotton flannel patches, the appropriate size to keep that jag and rod in the middle of the bore. You will need a good bore solvent, like KG 3, Shooters Choice or CR-10 to loosen the fouling, followed by a scrubbing with Holland's Witches Brew or KG 2. After cleaning, nullify the solvents with rubbing alcohol and patch dry. Finish with Tetra Gun Oil, KG 4 or Holland's Bbl Break-in Fluid. Never shoot a dry bore as this will greatly promote copper fouling.
Chris recommends:
Shoot one, clean, for first ten rounds; shoot three, clean, for next thirty rounds; shoot five, clean, while working up load. Allow bbl to cool to the touch before testing a new load to avoid unnecessary throat erosion.
Sweets 7.62 should scrub that copper out though, just make sure you neutralize it before putting it away.
Hope this is reading is of some use to you.
Rob