Restriction at breech

[Brianc]

I recently cleaned up an original Belgian 20 Gauge single barrel that looks to be very shoot able . However when I run a patch on a jag it gets stuck at the breech. I’m afraid to remove the plug as it’s got some ornate engraving that I really don’t want to screw up and honestly not certain what I’m doing. Anyone have anything they’ve tried that works in this scenario? Thank you

 

[Britsmoothy]

Patent breach maybe??

 

[Grimord]

Run a bore scope down the barrel to see what the restriction may be.

 

[FlinterNick]

Sounds like you have an extra thread that the breech plug wasn’t fitted properly for.

You should be ok as long as you clean it really well, however in the long run that could become an issue with corrosion.

If it were my gun, I’d send it to Bobby Hoyt.

 

[Brianc]

It’s definitely a patent breech . It’s coming clean in the bore but when bottomed out jag gets stuck then I use wood mallet on handle of range rod to jolt loose tempted to try and polish

 

[Grenadier1758]

There may be a bur at the breech or the loose fitting of the breech plug to the barrel or the transition of the chambered breech to the barrel is grabbing the jag and would need to be smoothed over. Any fix would require removal of the breech plug. To start the investigation, the use of an endoscope to look at the breech is a first step before removing the breech plug.

@Brianc, as a stopgap measure, I would consider filing a taper to the jag to provide a bit more clearance at the breech so the cleaning patch and jag may not get caught or that might just wedge the jag and patch tighter. You do want several full sized bands of the cleaning jag so the patch does bunch up and not get pulled off at the breech.

 

[Brianc]

This is percussion probably dating to 1850s-1860s patent breech was probably a cheap hardware store item when new just in good shape. I purchased with what was probably the original nipple broken but came out easy

 

[Brianc]

I don’t intend to use a bunch just an original I’m trying to save

 

[Grenadier1758]

@Brianc, Based on your anticipation of limited use, the stopgap measure might well be the way to go. As its an original limited use and looking for any signs of gas leakage at the breech should be sufficient. If there is any drop off of performance, stop shooting the gun until any breech issues are resolved.

 

[Brianc]

A few pictures

 

[Brianc]

UPDATE

Okay so I have been working on a new property with no time for toys.... this morning I had an idea (couldn’t sleep around 1 am ) I used smaller cleaning patches on the button jag and voila no sticking. In my opinion it was allowing the edges of the patch to roll around the jag at the breech area making it too big to make the trip back to the muzzle, when I extracted the stuck range rod I used a soft hammer on the handle until it ripped the patches (no drum but a hawken style bolster) I did use boiling water when I first cleaned it as it was FILTHY! It washed out lots of crud so now dealing with the flash rust. Break free CLP seems like it’s wiping it away I’ll have to keep an eye on it otherwise pretty much good to go

 

[Britsmoothy]

How about some scotch bright or wirewool.

 

[Brianc]

How about some scotch bright or wirewool.

Great minds think alike!! It’s helping and I soaked the scotchbrite with Kano Kroil