[Snakebite]

Does anyone have a rifle that leaves a bunch of copper in the bore?
I dont find it hard to remove using Sweets 7.62 but I have 2 rifles that will turn a cleaning patch green after a few rounds.
The 17HMR will lose accuracy after about 100 rounds because of it.
The worst by far is the 50BMG. I usually only shoot 10-20 rounds per session but dang. There is enough copper in the tube to recycle!
Other rifles dont seem to be affected by this. They just get dirty (duh) and the patches dont show the green copper.
Any reason? Velocity, pressure, heat, just plain lousy bullets?
Inquiring minds want to know. I do too.

[hounddawg]

I use Boretech Eliminator. I heve never seen anything eat the copper out of a barrel like this stuff does. I got put onto the stuff by a friend who works for Barrett.

This solvent is reasonably new, patent pending and all that.

http://www.boretech.com/introducing.htm

[wirehunt]

With the 50BMG does it affect the acccuracy at all?
I've found with any new stainless centre fires I've bought that around the 20-30 shot mark the fouling affects them, a good scrub out and there away. I may not need to do them again ever.

[Full MeTal Jack]

Some of the guys at gun club switch between moly-coated and regular copper jacketed in their ARs. Some use moly-coated all the time.
"Inquiring minds want to know."
In Savage 308 tactical, I thought I had a copper problem. Had it bore-scoped and found lots of copper. Several cleanings later and still wacky groups. Polished muzzle and cleared that problem up.
Shooting 50 cal, out of my league.

[Dale]

I've read where over a period of time the heat causes the moly to fuse to the barrel lining and eventually it effects accuracy.

From what I understand from the people that believe this is that it cuts down on friction to the point that the bullet slides down the barrel rather than having the friction to grab the lands and begin it's twist.

I even had one fellow tell me most major manufacturers of barrels and some gun makers will void a warranty if they figure out you used moly bullets.

I don't know how accurate the claims are....just what I have read and have been told.

[Marty]

I have a 308 that is terrible with copper fouling. Copper can be seen in the grooves when looking down the muzzle after only 20 rounds. I have started using sweets 7.62 and found it to be excellent for removing copper in only a few minutes with a wet patch.

I own a few other rifles that never show any signs copper fouling no matter what i shoot through them, I have been told that the smoothness of the bore is the reason why some rifles foul up and others dont.

[dave375hh]

Dale,
That's not how moly works. It doesn't fuse to the barrel from heat it coats the barrel and because of it's small molecular size gets down into the pores of the steel and only appears to bond to the metal. At no time under any circumstance has molly caused the bullets to slip the rifling and not engrave. Someone's blowing smoke in your direction about that. I use moly in five varmint rifles with it giving me just what I wanted out of it. I get a longer interval between cleanings, and I believe extended barrel life(jury's still out on the longer life thing). My .22-250 used to need cleaned at 20-25 rounds to hold it's accuracy. With the moly I can easly go 70-80 rounds without seeing a loss of accuracy.