What causes this line to mess up my rust blue?

[Nick_of_time]

Hey Folks,

I've been playing with the Mark Lee cold blue and really like the result. The last barrel came out great except for the line pictured between the barrel and breechplug. It's a Rice barrel with a TC breechplug installed. I don't blue many barrels so I use the technique where let the barrel rust, and then put it in a piece of PVC pipe, then pour boiling water over. The barrel does fill with water. I tried to seal the muzzle and nipple threads, but didn't get it tight enough. Would keeping the inside of the barrel dry solve the problem? any other ideas?
Thanks,
-Nick

 

[Edm]

Did you use something on the threads when you attached the breach plug?

 

[64Springer]

Did you use something on the threads when you attached the breach plug?

Agree.

Contamination of some kind that leeched out during the bluing process.

I'd leave it be. Doesn't look terrible.

But I'm sure it looks much worse to you.

 

[The Crisco Kid]

It looks like oil seepage. Clean it off with acetone before you apply the solution. That may help, maybe. If not, run a little cold blue on it with a toothpick and blend it in with some light rubbing with steel wool. Or, just ignore it.

 

[Phil Coffins]

No question, that’s oil wicking out of the joint and the blue won’t take. You must clean the oil or what ever is on the treads and joint.

 

[Nick_of_time]

Ok thanks folks. I acetoned the whole thing to remove the surface contaminants, but did not remove and clean the breechplug threads. I had a gunsmith install the breech plug, so I need to either tell him to not use a sealant/oil, or just do the two pieces separately.
No, it doesn't look that bad, and I'm going to happily shoot it as is. But I intend to make more guns (flintlock next) and just want the next one to look better.


-Nick

 

[Eric Krewson]

I think some kind of anti-seize is a necessity on the breechplug threads. You may never take the TC breechplug out again but if you build a rifle with a standard breech plug you will have it in and out a bunch of times during the build.

I think your gunsmith did a sloppy job, he apparently put oil on the threads and everything else which oozed out when he tightened the plug.

I put gobs of high temp anti seize on my plug threads, only the threads and have never had any ooze out around the tang and disrupt the browning or bluing which I rub back to gray.

 

[54ball]

That may not be oil seepage.

It could very well be where the joint line was “ upset” when the breech was mated.
Carding revealed the high spots.

 

[wiscoaster]

I'm thinking time will heal.

 

[BJHabermehl]

That may not be oil seepage.

It could very well be where the joint line was “ upset” when the breech was mated.
Carding revealed the high spots.

Definitely oil seepage. Sorry fought that battle before. Now I clean everything with electric motor cleaner before assembling and use blue lock tight on the threads sparingly. Haven’t had a issue since. BJH