Copper Gas Checks and Boolits

[GregLaROCHE]

I have always heard it is important to clean your bore of all copper deposits before starting to shoot cast boolits. So what is happening with the copper of the gas checks? Is it just insignificant or do we have to have to clean the bore often with a de-coppering agent?

[Hick]

I have the impression that the need to clean copper from the bore only applies to real precision shooting. I switch my rifles back and forth between jacketed bullets, and plain based lead and gas checked lead frequently and only pass a bore snake through them between trips to the range. Of course, I only shoot open sights, so the smallest thing I shoot at at 100 yards is a 2" gong, but at that degree of accuracy the copper does not appear to matter.

[JonB_in_Glencoe]

Just a guess here, but two things that pop into my mind.

1. Typically a cast boolit with a copper GC is lubed...I suspect the lube may inhibit copper fouling.

2. Typically a cast boolit with a copper GC will obturate to seal the bore, whereas a J-word typically doesn't and some gases may flow past the bullet and in doing so, would heat it up beyond just what the friction would, and I suspect that can exacerbate copper fouling.