Short Started / Ringed / Bulged Barrels

[BrownBear]

Good brain food in this thread, Roundball.

Thanks for posting.

I've always been leery, for fear that the ringing or bulging could result in weakening of the steel with ruptures on subsequent firing. That would be distinct from a jug choke which is honed. Shows how little I know about metallurgy, but also that I've experienced barrel ruptures or seen their consequences.

I've always been curious about patch integrity when RBs pass through jug chokes. Certainly case-by-case and depends on degree of jug choking or ringing, but my ears twitched when someone in this thread posted such experiences with a ringed barrel.

You've done as much or more testing than most of RBs and jug chokes, Roundball. Have you experienced any patch problems?

 

[Stumpkiller]

I've got a jugged 12 bore (55% choke - modified +/- from a 40% cylinder start) and it has no effect on patches. Shoots a round ball as well as ever. But that's a smoothbore and the rifling doesn't have to "reattach" after hopping the relieved area.

 

[roundball]

A jug choke's expansion chamber of course is hugely larger diameter than the slight 'ring' cause by an unfortunate short start bore obstruction, and my PRB accuracy is fine in Jug Choked smoothbores.

For example, the Rice .62cal barrel I bought and sent to TVM for a Virginia build first went to Danny Caywood to have a Full Jug Choke installed, and not even using a bench rest, just sitting down in a hunting/shooting position it gives 2.xx inch groups at 50yds with a deer hunting load:

110grns Goex 2F
Oxyoke .022" patch
Eddie May cast .600" ball

 

[BrownBear]

But that's a smoothbore and the rifling doesn't have to "reattach" after hopping the relieved area.

That sounds like an important distinction.

Thanks for the comeback, Roundball. I recalled your reports of stellar accuracy, but couldn't recall anything about the patches.

 

[roundball]

Like I've said, there two issues to the discussion:
1) Is it safe
2) Is it accurate

Also, we need not let the sort of general reference to a Jug Choke's expansion chamber be taken to the extreme...from everything I've heard about a ringed barrel, its at a tiny narrow spot...not a 3" long .025" oversized expansion chamber.
My gut is that a PRB wouldn't totally disengage from the lands and fly through space at such a ringed spot like a large expansion chamber then re-engage lands...the accuracy comes from patch steerage down in the grooves and I can't see how there would be any patch/groove dis-engagement due to that brief tiny ringed area.

Like I've said, if it ever happens to me, I'll want to shoot it to see if its still accurate for the hands on experience...and IMO, it wouldn't surprise me if there many out there over time that have been and are still being shot by people in two categories:
A-Those who know they've ringed their barrel
B-Those who don't know it

Interesting topic to explore...

 

[BrownBear]

Interesting topic to explore...

Amen to that. :bow:

 

[paulvallandigham]

It all comes down to WHERE in the barrel you have a bulge, and how large the bulge is( Ie. is it only felt inside the bore, or can you see it on the exterior of the barrel).

If the bulge only is felt inside the barrel, I can't see much affect on accuracy, unless its within 8 inches of the barrel, and even then, it may not have an effect.

We need to remember that that PRB is already spinning in "sync" with the grooves in the barrel when it passes thru the slight enlargement you can feel with a tight patch and jag. IF the bulge is not large enough to be visible outside the barrel, Its likely to be so small as not allow the patch to curl back off the ball, before it re-enters the rifling in front of the bulge, NO?

I have also know other shooters who have been shooting barrels they have "ringed" and didn't realize what it was, with no apparent drop in accuracy.

I have not short-started a ball, because I am very serious about safety. I have had people try to interrupt my loading procedure, and have always told them to STOP until I have the PRB seated properly on the powder. It only takes a few seconds to run the ball down the barrel and seat it properly, in my experience.

On one occasion, The Range officer closed the firing line, for an emergency involving another shooter, when I had just short-started a PRB. I left the short starter in the barrel, to remind me where I was in my loading sequence until the line was re-opened.

For these reasons, I would not hesitate to shoot a rifle using targets loads, to start, to check to see if its still accurate. Once that was established, I would go ahead and use the gun with any load, PROVIDED the bulged area is not back near the breech where the ball is seated normally. Really, the pressure in the barrel drops off so much by the time the ball nears the muzzle, that I just don't see steel barrels rupturing when normal loads of BP are shot thru a barrel that has been lightly ringed. Where the Pressure is much higher at the breech end of the barrel, There I would use caution in raising the powder charges, or using Faster burning brands of BP.

I think the problem we have here arises because we do not have this problem barrel in our hands to inspect ourselves. That makes it difficult to make a general recommendation to the poster. I think its important enough that we discuss the Analysis of the problem, and the factors we would consider if we were presented with such a barrel to examine personally. :hmm: :hatsoff:

I think shooters can learn something useful by reading what others, who have had this experience, consider critical factors in deciding whether a barrel is still safe to shoot or not.

 

[mbokie]

I'll try to get some decent pics.

You can see the bulge a bit on one flat and it's the distance of the length of an RMC short starter from the muzzle.

But the ring is the entire circumference of the barrel.

 

[roundball]

You said you were only using a 60grn charge of powder and frankly that's pretty much an entry level, milk toast, powder puff charge...I can't imagine there being any structural damage to the barrel from only 60grns but you need to do whatever you're personally comfortable with.
:wink:

 

[mbokie]

Well, trust me, I want to shoot it. But the nays seem to have as much weight as the yays.

It's a long way to January. No bp flint shooting in all that time may be more than I can deal with. Withdrawal is a heavy price. :haha:

I just put it back together this a.m., so I didn't lose any parts. It hurt. :redface:

Stupid has a price to it. This may be mine.

 

[roundball]

Fullstock or half stock?

 

[mbokie]

Is that how stupid is measured around here?

I'll pass on judging that. :haha: I would likely get it wrong.

If it's about the rifle, it's a full stock. It's a pedersoli Pennsylvania.

 

[roundball]

Quit beatin yourself up...its not stupid, its just one of those little human things...and you're sharing it helps all of us in terms of it being a good reminder

 

[mbokie]

Well that's a good thing.

And thank you kindly for the encouragement.

Maybe it's not stupid if it can be fixed. :grin:

I'm just sitting here thinking I should be out shooting on such a gorgeous day.

Say I have my last patch from that shoot. Would it reveal anything?

 

[mbokie]

Hope that is good enough.

 

[roundball]

Well, good lord.....there's the problem.....the patches have push-pins at their corners !!!!!







No...that wouldn't show anything...it was just sitting there waiting to be seated down when ignition occured.

The gas pressure in the bore ramped up shoving a bore full of compressed air into the back of the ball.
The ball's inertia takes a moment to be over come before it starts moving but the gas pressure is still building and won't wait.
So the metal around the circumference of the ball starts to stretch ever so little (causing the ring) until pressure starts leaking past the ball and/or the ball finally pops out of the way, allowing the pressure to collapse completely.

 

[Stumpkiller]

Quit beatin yourself up...its not stupid, its just one of those little human things...

I agree 100% Not too long ago I fired a shot that was all noise and no recoil. At 50 yards there was no hole in the target. I wiped the bore and felt a catch and then jump about 6" behind the muzzle. "Oh crap!" I thought, as all the blood drained out of my face and my hair stood on end. But, as near as I can guess, it was a powder with no ball at all shot! (I counted the holes in the target less what was left in my ball block and multiples backwards. All target holes accounted for. The fouling really cruddied up the bore, but after the second spit wipe there was no odd spot in the bore and nothing visible.

It only takes a moment of distraction - and our lives are full of distractions.

 

[mbokie]

I'll start feeling a lot better about it when I have that new barrel. And do something with the bulged one.

I do appreciate the encouragement.

:hatsoff:

There's no way I would ever quit. Ever.

 

[Fred_Dwyer]

No worries. If you want to save a few dollars make up a lapping slug and lap the barrel from the bulge to the breach. You'll have a choked bore and some have tried that to increase accuracy. The gun will load slick as snot when ramming a ball home after you pass the choke. As to skipping the rifling; that is maybe an inch of bulge, in a 1:60 twist that would be about 4 degrees of rotation. BUT WAIT! the ball is spinning 18,000 rpm, why should the ball stop spinning for that 1 inch of slack in the rifling?
I've shot a bulged barrel for years. I even run some seriously rhino-rolling loads through it. Like the barrel maker said, "fugeddaboudit."

 

[mbokie]

Our rifle club has one of those gizmos that you can shoot without touching the rifle. I was thinking of trying a 68 grain load. which is more than I've ever had in the barrel.

I'm needin' to smell some smoke.

I'm seriously goin' to and fro on this thing. :surrender: