Random copper 1/2-4/3 down the barrel

[King_beardsly]

So after chasing my tail with load development trying to get my current 223 rifle project all set, I ran a scope down the bore and noticed what looks like random copper fouling 1/2-3/4 through the barrel in a couple spots. It also looks like a possible rough patch in the bore but I can’t definitively say because I’m not a gunsmith nor pretend to be one.

Now I don’t know if that’s just due to it being a semi fresh barrel (325 rounds through it) or if there’s actually a problem with it since I’ve never experienced this issue before. I played with powder, seating depth, virgin vs once fired brass and I can’t get it to consistently shoot a tight group, best I can get is 3/4-1” or its making two distinct groups that on their own would be awesome but not in the same string of fire.

I’m going to reach out to the barrel manufacturer in the morning and see what they think about the situation, but figured I’d get some people’s input/advice. So I’m not going to bad mouth them because that’s not fair and I understand that sometimes things can get a little cattywompus, but they do have a pretty solid reputation.

 

[spife7980]

Maybe clean the copper fouling?

 

[King_beardsly]

Maybe clean the copper fouling?

I cleaned it about 100 rounds ago, scrubbed it out with bore tech copper remover and then some bore tech eliminator.

 

[JerkyFreak]

Copper fouling further down in the bore is usually caused by the throat. The friction on engraving, specially newly chambered barrels or barrels with a lot if fire-cracking, heats the jacket to almost a plasma. This then condenses on the barrel further down the bore as the gasses cool down slightly. This is the main reason for barrel break-in.

This has been confirmed by recovering fired bullets with melted copper on the boat tail area. Powders with so-called "CFE" (copper fouling eraser) has some compound in them that tries to prevent the condensation on the barrel steel.

 

[Ronin22]

I've found in factory barrels that copper "fouling" or light streaks isn't a bad thing if it's just filling cracks in the barrel. That's a bonus. Copper build up is a problem but has to be quite severe. I quit trying to remove all traces of copper from barrels, but do make sure to clean out all hard carbon. Especially the carbon ring area. The premium custom barrels will/should have much less coppering due to the hand lapping and stricter quality control.

 

[supercorndogs]

The way you describe how its grouping sounds like a bedding problem.

 

[diggler1833]

I'd double check that chambering job. I had a nice cut rifled barrel that copper fouled like mad just like the OP. Took it to the gunsmith who nornally does all of my barrels (not this particular one though), and we noticed with his borescope that it looked like whoever did this barrel had managed considerable runout in the leade.

That barrel still shot okay, but 1/2 - 3/4 of the way down it collected copper like an Ozark meth head.

 

[King_beardsly]

The way you describe how its grouping sounds like a bedding problem.

Shouldn’t be since it’s sitting in a manners TCS with mini chassis but anything is possible at this stage. I might throw it in my spare PRS1 just to eliminate that variable.

I'd double check that chambering job. I had a nice cut rifled barrel that copper fouled like mad just like the OP. Took it to the gunsmith who nornally does all of my barrels (not this particular one though), and we noticed with his borescope that it looked like whoever did this barrel had managed considerable runout in the leade.

That barrel still shot okay, but 1/2 - 3/4 of the way down it collected copper like an Ozark meth head.

Haha Ozark meth head is a good analogy

 

[supercorndogs]

Sitting in a minichassis doesn't eliminate the chances of a banana shaped action. A chassis or bedding block has always been how I found out an action didn't quite lay straight. It's the first place I go if a rifle is shooting as you described.