Jonathan Browning Mtn. rifle

[topbike]

I recently purchased a JBMR and on arrival I discovered that it had been stored loaded. I managed to remove the charge however it was obvious by its condition that it had been in there for years. I ran a wet cleaning patch down the bore and when I tried to pull it out it was stuck in the bore. I managed to remove it and the patch was torn to pieces. I tried another patch and then several more experiencing the same problem. The patches were rusty as well as torn. Obviously that charge has led to corrosion in the barrel. If it was rough farther up the barrel I would use some valve grinding compound on a green scrubbie and try to smooth it out. This however is right at the breach plug so I can't go past it to polish the barrel up and down. Now here is my idea. Would it make any sense at all to take an old bench rod and put a scrubbie with compound on the end shove it down the barrel, chuck it up in my drill and try to polish the barrel that way. any comments or suggestions gladly accepted.
thanks. :bow:

 

[galamb]

That's sounds reasonable - I would certainly give it a try.

With your issue being right down near the breech it shouldn't effect the accuracy of the rifle if the barrel is otherwise in decent shape.

But you do want to stop whatever is going on down at the bottom...

 

[topbike]

I actually have shot it and although it is a mite rough to load it will still put all 5 in a pie plate at 25 yds. I'm hoping if I can clean up the breech and work up a proper load that it will have at least acceptable accuracy.

 

[fleener]

consider pulling the breach plug.

if you really need to clean it up down there you might want to pull it and take a look as well.

Fleener

 

[Grenadier1758]

One of the better shooters in my gun club had a rifle that had a tiny bit of roughness right at the breech. This was a rifle that regularly cut clover leafs in his targets and suddenly all accuracy was gone. The bore was perfect except for that bit of roughness at the breech. He tried all sorts of smoothing techniques to remove that rough spot. It finally took unbreeching the barrel and removing about 2 inches of the breech. With the breech plug reinstalled, excellent accuracy was restored.

It will take more than a minor bit of effort the cut out the rough spot on the JBMR barrel. As I recall from very old literature, the JBMR breech plug is silver soldered to the barrel. Not to mention moving the under lugs and shortening the under rib, the task will be some work.

I agree you should try to smooth out the breech. Also you should make up a load with either wads or corn meal filler to raise the PRB above the rough spot.

Good luck with your rifle.

 

[larry wv]

How about a rebore ?

Larry

 

[topbike]

I thought about that but if I have it re-bored it will need a different breech plug and there are no parts available for this rifle anymore. The question then becomes would a different brand fit it and how much work would the tang need to fit.

 

[larry wv]

Seems to me your old breech plug would work. I expect somebody will know.

Larry

 

[rushlake1]

at 25 yards they should be clover leafing..not pie plating.

Had the same issue on a new to me barrel...

Pull the breach plug in inspect the bore...
unless you can find someone with a bore scope.

You will have nonstop fowling and cleaning issues until bore is pristine.
Bobby Hoyt does barrel relining..as do others..

scrub it out if you have ambition otherwise send it out to a pro. You'll be glad you did.

 

[don hepler]

I bought a 32 Cherokee and the bore was really pitted. I had difficulty loading it, and accuracy was poor. I used a metal rod and scotch-brite with polishing compound, until a patch came out clean. I load a tight ball/patch combination, with Black MZ powder and the accuracy is as good as my 36 Seneca. The powder leaves very little fowling, allowing me to shoot a much tighter patch. I was just about to have it rebored, when I gave it one last effort, and it worked for me.

I would smooth out the pits as much as possible and load the tightest ball/ patch combination. I use a ball starter and wooden mallet, and I use a metal ram rod. It sounds like you have nothing to loose. Heavy patching materiel and thick lube, will let it engrave the rifling, and hopefully won't tear the patch.