Help - possible barrel bulge

[Rifleman1776]

The biggest issue on the bulge is probably gas cutting

:nono: Disagree big time.
If the barrel is bulged that is a sign the integrity of the steel has been compromised. The biggest issue is safety.

 

[nkbj]

I was once upon a time sold a Shenandoah .36 flinter with a bulged barrel. Now it's .46 and shoots the same ball as the .44 Colt.
:wink:

 

[pjmcdonald]

Gents,

Thank you for the good advice. It will be a few weeks before I can get back to the range. But I have the following chores:

- mic the barrel to see if there truly is a bulge or if more likely due to corrosion

- clean and scrub the bejesus out of it to try to get corrosion out, various methods suggested and will be tried

- buy several patch thicknesses to experiment with. Treat with lube, tag, bag, document everything

- purchase small light from auto store, as recommended

- potentially buy new barrel. Go through above first. If no bulge, comes clean, then load development. If bad barrel, buy new. Might buy new anyway...working on that with chancellor of the exchequer.

As to the question of sentiment, yes, this gun has value to me. But if it needs a barrel, it needs a barrel.

May try wads but will work through above first.

Miss anything? Thanks again for valuable input. I feel like the Lone Ranger, shooting BP around here. Haven't met anyone locally that still does. Hunting laws changed locally to allow historic single shot cartridge rifles or replicas. Like 45-70. Hence the dearth of BP rifles and supplies. Most guys dumped them and stores quit carrying supplies (except those odd in-line types - just WRONG).

Will be glad to provide follow ups as I progress in reviving the old TC.

Paul

 

[Grumpa]

You are on the right path. First step, mic.
We will all anxiously await your updates.

 

[Rifleman1776]

I was once upon a time sold a Shenandoah .36 flinter with a bulged barrel. Now it's .46 and shoots the same ball as the .44 Colt.
:wink:

And, now you are a proud member of the "IT AIN'T BLOWED UP YET" club. :applause:

 

[crockett]

Well one last thought. Obviously if the bulge is bad and there is a lot of gas cutting etc.- then you might not be able to do much with the barrel. Some barrels also seem to have a "slick spot" that is noticed while ramming down the ball and they usually don't cause too much trouble. On the wads- sometimes it helps and sometimes it doesn't make any difference.
Just in case you don't know- a conical creates a lot more internal pressure than a patched round ball. The patched round ball is less expensive, easier to load, doesn't lead the bore like a conical. I don't shoot anything else.
In the case of a bad bulge- you may still be able to use parts of the barrel for single shot muzzle loading pistols. You'd have to look at the existing dovetails locations and where these dovetails need to be on a pistol prior to cutting the barrel.
As others have noted- safety should always come first. If it is a bad bulge in a weak area (base of dovetail, etc. then the barrel probably isn't ever going to shoot well and ought to be switched. If it is just a slick spot and the area doesn't mike out more than other areas- probably okay to test a variety of loads.

 

[Billnpatti]

One thing I failed to mention is that the "bulge" could possibly be due to a manufacturing error. If they tightened the clamps too tight when they were boring the barrel, it would have caused the metal in the area of the clamps to be compressed. The bore would have been bored out and when the clamps were released, the metal would have come out of compression resulting in a loose spot where the clamp was. I once bought a "Match grade" barrel from a well known barrel maker and it proved to have three of these spots. I didn't find them until the rifle was complete. You could only feel them when you used a well lubricated and tight fitting patch and ran it slowly down the barrel feeling carefully for the loose spots. Even with those spots in the barrel, it was a tack driver. So, you may not have a bulged barrel, it just may have a manufacturing error. Such errors do not constitute any kind of safety issue and, in my case, did not effect the accuracy of the barrel.

 

[MAN - GA]

FWIW my TC 50cal setups shoot best with about 60-65gr FF. Anything over 70gr begins to open up or become inconsistent and this is a couple different guns. And if hunting is what your after 60gr FF and roundball will shoot thru a deer no problems. I am of the opinion you need to shoot lower powder charge b/c you stated sabots shoot 1/2 size groups so I don't think the issue is a bulge. Although it is worth investigating for safety sake
Remember to only change one thing at a time during load testing

One last thought is how did you test to feel a bulge - if the barrel is upright and you push down range rod there is a point where all your force is high and then your arms get horizontal and it could be the change in angle of the force applied has the "feel" of a bulge. Clamp the barrel in a vise with some padding and use the range rod and the force applied will be horizontal and more consistent/even during the full stroke - just a thought to see if there is any different feel in the two methods
Good Luck and have fun

 

[nkbj]

Something's fixing to come out. Watch for it.
Yep, here it comes.

:dead:
IT AIN'T BLOWED UP YET CLUB

 

[Ohio Joe]

If you're uncertain about the barrel and advise offered here (one way or the other), just take it to a qualified gunsmith to have your questions and options answered.

 

[crockett]

On the safety issues, some modern handguns have ported barrels to reduce muzzle flip/lift. A lot of semi-autos have gas ports in the bore to reload the slide, shotguns have jugged chokes (sort of a bulge). I really don't know the issues involved but a barrel with a bulge...is there a danger or is it just unsightly?

 

[cynthialee]

Cut that barrel into pistol barrels.

 

[Zonie]

... I really don't know the issues involved but a barrel with a bulge...is there a danger or is it just unsightly?

IMO, it depends on the amount or size of the bulge.

If it can be seen by just looking at the outside of the barrel, I wouldn't trust it for shooting.
It might make a good fence post.

If the bulge can't be seen by just looking at the outside of the barrel, I don't think any great harm was done to the steel. After all, millions of steel parts are formed in presses and dies that bend the steel without a loss of strength in the formed areas.

As for shooting, that's a different subject.

If there is enough of a bulge to make a patched cleaning jag suddenly "feel loose and then return to its former resistance as it is pushed down the barrel", there is enough difference to cause the high pressure powder gasses to blow past the patched ball.

As soon as the flaming, hot gasses blow past the patched ball, the patch will be burned and accuracy will go out the window.

I speak from experience on this.

Years ago, I bought a CVA Mountain rifle that looked in great condition. Stupid me, didn't check the bore for bulges.

At the range, I couldn't get it to stay on a 8 1/2 X 11 piece of paper at 50 yards, shooting from a bench.
I tried many different loads with no improvement.
The retrieved patches all showed signs of burning where the ball met the barrel.

When I got home and started cleaning, lo and behold. A loose area about 2 inches long, about 12 inches from the muzzle.

The ole' barrel bulge got me.

 

[nkbj]

If you're uncertain about the barrel and advise offered here (one way or the other), just take it to a qualified gunsmith to have your questions and options answered.

Yep, that's what I did. The man who rebored it knows way more than me about barrels.

 

[crockett]

Thanks Zonie for the real life experiences. The pistol barrel option may be the best bet.

 

[pjmcdonald]

Ok, quick update. I still haven't been able to go to range with it but I have cleaned, measured, and put a light down the tube. The good news - no measurable bulges using digital calipers. The bad news - fair amount of pitting the first 3" or so down the bore (muzzle end).

Using a green scotchbrite pad, pulled apart and wrapped around a .40 cal brush, some solvent, and a lot of elbow grease, I was able to get it cleaned to point patches would come out clean. Carefully measured full length of barrel exterior and found no bulging. Though I suppose it is possible there might be a cavity, I can't imagine a bulge that wouldn't show change in exterior dimension as well. Still one very slight loose spot, no more than 1/4" long, about 22" down from muzzle end.

I will try patch combos to see if I can tighten groups up but looks like I'm barrel shopping due to pitting. Grooves look pretty shallow and lands are uneven close to muzzle. Right where I'd expect most influence on ball flight.

Thanks again for good counsel. Look forward to many years enjoying this hobby! (Or affliction!)

Paul

 

[Rifleman1776]

I can't imagine a bulge that wouldn't show change in exterior dimension as well.

That is probably a good sign. Good luck.

 

[Grumpa]

Imagine that...no bulge. :shocked2:

Fortunately, you haven't welded it shut, or cut it into pistol barrels.

Some repros are made with shallow rifling, and pitting may or may not adversely affect accuracy.

Before you buy a new barrel...shoot it...shoot it...shoot it. Try various load combinations. At worst, you may find it is not accurate to your requirements. But your shooting will have benefitted.

At best, you may find a load that meets your needs...and your shooting will still have benefitted.

Have fun. :thumbsup: