ORIGINAL: herman
I think you said you had gotten the sps varmit?I have the sps in a reg barrel (blue) and have shot many hot loads in it but haven't had a problem with copper,maybe one barrel is rougher than the other.
A very good copper remover is JB's bore cleaner and Montana 50 BMG.
I agree with these two products..
There is also a very good arical about overcleaning barrels and mentions a copper fouling preventing product (can't remember what its called though) as well..Its in the Latest Handloading Mag.....
There might be some truth in whatthe author sayssays..