How to know if it’s safe to shoot

[Goneshoot'n]

About 10 years ago I had a side job reloading for a couple guys who own a small gun store. They gave me an old cap and ball rifle. I don’t know much about it, not many markings other than “Jukar”. I know it’s nothing special, but I’ve had lots of fun with it over the years. Never thought to scope the barrel until today. It looks like there is quite a bit of rust and putting at the breech end of the barrel. Also a lot more moisture than I thought, I hope it’s just balistol and not water from cleaning. I do use lots of balistol after the soapy water. What concerns me is the gap between the barrel and the breech plug, it’s hard to see how much corrosion is in there. It would be nice if it wasn’t welded… last thing I want is a breech plug coming back in my face at Mach 6. I’m ok with that being the answer to my question, retiring this rifle and buying a new one, but I’ve grown quite fond of this one. But maybe it’s normal? I don’t know. Thoughts? Have a look at my fine photography.

 

[hawg]

That's pretty skundgy but it still might shoot ok. What concerns me is the welded breech plug. I wouldn't shoot it and I'll shoot a lot of stuff that would make other people cringe.

 

[Jackrabbit1957]

My question is why is that ring so shiny when everything else shows pitting and signs of corrosion? Is there any sign of the breechplug separating from the outside of the barrel?

 

[noelf2]

Bore scopes always make everything look 10 times worse than they are.

 

[Goneshoot'n]

My question is why is that ring so shiny when everything else shows pitting and signs of corrosion? Is there any sign of the breechplug separating from the outside of the barrel?

no sign of damage from the outside. I was wondering if the powder doesn’t fully settle into that gap when loaded, and when fired provides air space for gasses to expand, which as I understand causes a pressure spike, might blow everything out? These were taken right after shooting and cleaning. Is this gap normal?

 

[Jackrabbit1957]

I can't tell if its the rim from the breech plug or an actual separation of the two parts. Its certainly not something I would expect to see. Might want to get a second opinion.

 

[hawg]

When you said welded I thought you meant on the outside. AFAIK there's no way to weld one on the inside. I think what you're seeing is the patent breech.

 

[Jackrabbit1957]

That's what I was thinking, but why is it so shiny in the one area?

 

[dave951]

The bore isn't too bad. You just need to polish it up a bit. The breech is a "patent" breech with a subcaliber powder chamber. As long as the nipple isn't rusted out, it's probably fine to shoot. As for the rifling, I have one with rifling that looks far worse and I'd use it to shoot for money pretty much any day. After firing the patch looks like shredded lint, but darn if that gun can't shoot.

 

[Goneshoot'n]

I guess this is what I was talking about when I said welded. You can see the seam all around the breech plug except for one spot, to me it looks like it’s been tacked and ground smooth. Maybe I’m mistaken?

 

[hawg]

It wasn't welded. Polished over perhaps to even up the fit between the breech plug and barrel.

 

[Mizar]

Maybe it's just me, but I don't see any pictures of the breech plug face - only the bore scope mirror and it's reflections.

 

[dave951]

Quit stressing, clean it up and shoot it.

 

[hawg]

Quit stressing, clean it up and shoot it.

Amen to that.

 

[J-Bar]

Re-proof it. Load it with twice as much blackpowder as you ever expect to use under the heaviest projectile you will ever use, hide behind a secure wall/tree, and use a very long string to pull the trigger. You will know whether or not it’s safe after that!

 

[4v50 Gary]

Re-proof it. Load it with twice as much blackpowder as you ever expect to use under the heaviest projectile you will ever use, hide behind a secure wall/tree, and use a very long string to pull the trigger. You will know whether or not it’s safe after that!

After visual inspect and if your mechanic has a magnaflux (to find more latent cracks), the do as J-Bar suggested. Remove the barrel from the stock and secure it to a heavy object. Overload with powder (that depends on the caliber) and then from a distance and behind a barrier that will stop shrapnel ignite it (cannon fuse perhaps?). Then inspect. Dixie Gun Works catalog has instructions on how to do this.