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Posted By: Shotgunjones Why don't shotguns ring chambers? - 08/12/20 02:39 PM
I have a black powder cartridge rifle in production. It's my first.

I'm studying loading both black powder and smokeless. My rifle will be a 45-70.

Cautions abound to not leave any air gap above the wad(s) with black, and to not use any wads with smokeless.

This is to avoid 'ringed' chambers. The mechanism most cited for this when it occurs is the bullet acting as an obstruction while air in the case is compressed to a very high pressure causing the ring.

The fellow who runs Shiloh Rifle has on his website a photo of a barrel sawed in half lengthwise that reveals TWO chamber rings, one where the base of a 405gr bullet would be, and one at the base of a 500gr. There is thus no doubt that this does occur.

Since the volume of air in the cushion section of a plastic shotgun wad is so large, the question I have is why does not a shotgun exhibit this phenomenon?
Posted By: Recoil Rob Re: Why don't shotguns ring chambers? - 08/12/20 03:16 PM
Lower pressures?
Posted By: John Roberts Re: Why don't shotguns ring chambers? - 08/12/20 03:46 PM
40,000 psi vs 10,000 psi.
JR
Posted By: craigd Re: Why don't shotguns ring chambers? - 08/12/20 04:08 PM
If ringed chambers are ring bulges, maybe it can happen in shotguns? Maybe, plastic hulls can’t hang up like brass? It could be that it might not be so easy to replicate a rifle cartridge type void in a shot shell?
Posted By: Tim in PA Re: Why don't shotguns ring chambers? - 08/12/20 04:43 PM
Two possibilities I can think of.

There is a lot of airspace in the wad, but the force required to collapse the legs in concert with the lower pressures involved, keep pressures from spiking.

The other is that the shot charge is easier to force down the bore so pressures don't get a chance to spike. When a 500 grain bullet hits the rifling, it's going to want to stop, spiking pressures.

Tim
Posted By: John Roberts Re: Why don't shotguns ring chambers? - 08/12/20 06:21 PM
Originally Posted By: Tim in PA
The other is that the shot charge is easier to force down the bore so pressures don't get a chance to spike. When a 500 grain bullet hits the rifling, it's going to want to stop, spiking pressures.

Tim


Agree.
JR
Posted By: Shotgunjones Re: Why don't shotguns ring chambers? - 08/13/20 06:05 AM
I've considered all this.

The rings form where the base of the bullet is in the cartridge, so it would appear that rifling engagement has not yet occurred. In fact, there has been no bullet motion.

Inertia is inertia. An ounce is 437 grains, no matter if it's shot or ball.

True, shotguns do operate at lower pressures than rifles. These are black powder rifles though, and the difference isn't that huge. A trapdoor 45-70 load is in the area of 17K PSI for instance and a 3 1/2" 12 gauge is SAAMI specified at 14K PSI. They don't seem to ring chambers like rifles.

Kirk at Shiloh has stated that if you use the standard load of AA 5744 in a 45-70 case (which fills the case about 50%) and then top it with a wad in the mistaken belief that this is necessary to keep the powder in contact with the primer it will ring the chamber EVERY TIME. That has to be caused by a mammoth air pressure spike between the wad and the bullet and not the natural chamber pressure of the expanding powder gas. The load works fine with no wad. People use it regularly.

There's plenty of air in a shotgun shell between the over powder section of a plastic wad and the shot cup. There's a collapsing section between the two, but it sure does not seem substantial especially in the case of something like a Windjammer. 11,500 PSI in a standard load would seem enough to just smash that flat as if it wasn't even there.

What happens to the air? It can't go anywhere, just like the air trapped a in rifle cartridge that appears to compress and expand some really strong steel. I can't imagine what the actual pressure might be to actually do that. It must be enormous.

Obviously, this does not happen in a shotgun and shotgun chambers are generally not as thick and strong as rifle chambers.

I'm certain you're right about things happening more gradually in a shotgun, but this just boggles what little mind I have left.






Posted By: keith Re: Why don't shotguns ring chambers? - 08/13/20 06:21 AM
I'm not so sure that the problem of ringing chambers in rifles has much to do with the difference in chamber pressures vs. shotguns, because each is designed to handle normal chamber pressure with a margin of safety built in.

Originally Posted By: craigd
It could be that it might not be so easy to replicate a rifle cartridge type void in a shot shell?


craigd makes a good point here, and a compressible plastic wad might replicate the function of fillers such as dacron in nitro for black rifle loads.

I'm using 13 grains of dacron with 4198 smokeless loads in my .450 Black powder express, with no sign of chamber ringing so far. But I have been strongly considering just switching to around 120 grains of 2Fg black powder because of warnings that it is only a matter of time before I ring the chambers.

I've wondered if it could happen because of not using enough dacron filler. It is a pain in the ass to stuff all that dacron in before seating the bullet, and I can imagine that some might want to use less than what is recommended. Yet it now occurs to me that I have also been shooting various published .45-70 loads of smokeless in my Marlin 1895 and other rifles without any filler whatsoever. And these loads are quite a bit higher chamber pressure than standard .45-70 SAAMI loads. There are many sources that say it is a must to use dacron or some other filler in double rifles when loading nitro for black, but nobody even mentions it when shooting cartridges like the .45-70 in Marlins, Siamese Mausers, Ruger no. 1's, etc. I do understand that there is a lot more air space in a 3 1/4" .450 BPE than in a .45-70 loaded to similar velocities. I suppose the chambers could be much thicker in these rifles than in typical double rifles. But this does raise some questions.
Posted By: Shotgunjones Re: Why don't shotguns ring chambers? - 08/13/20 06:36 AM
I'm planning to start with AA 5744 in the 45-70.

Western Powders states to NOT use fillers or wads. They have me convinced.

They also make the claim that one reason AA 5744 works well in the old BP cases is because of it's low density but that would appear to be simply false. Looking at the Lee density table that comes with their volumetric powder measure 5744 has typical density for a stick type powder. A double charge would fit, and that would lead to disaster.
Posted By: keith Re: Why don't shotguns ring chambers? - 08/13/20 07:09 AM
There is currently a discussion concerning the use of fillers in the Double Rifle forum. Not surprisingly, there are opposing views echoing what I have read elsewhere, and some interesting theories.

One guy says that chamber ringing is a gradual thing that may not be noticeable until it is too late, and case extraction becomes difficult. Another guy says that ringing will not occur with dacron, providing the correct amount is used.

And the recommendation from BrentD concerning the use of a small amount of flower arranging foam on a small smokeless powder charge sounds like a recipe for disaster, according to what Maj. Burrard had to say on the subject of chamber ringing. Not that I would even consider following any suggestions from BrentD on anything.
Posted By: SKB Re: Why don't shotguns ring chambers? - 08/13/20 09:55 AM
Backer rod is not flower arranging foam. Your ignorance is on full display once again.

Were you to be interested in learning instead of slinging mud, you might read Graham Wright's book "shooting the British Double rifle" as it covers the subject of back rod quite well.
Posted By: Shotgunjones Re: Why don't shotguns ring chambers? - 08/13/20 02:11 PM
Thank-you for pointing out the thread in the DR forum keith. What a coincidence.

I was unaware of Burrard writing on the subject. Likely read that years ago and since I had no use for the information then just forgot about it.

Quite an interesting subject.

The part about shooting straight up and causing a ring would seem to verify the pressure wave mechanism as real.

In a shotgun, the crush section apparently defeats the pressure wave.

Posted By: craigd Re: Why don't shotguns ring chambers? - 08/13/20 02:30 PM
It might be that these problems are not happening due to bad luck with normal pressures, these seem to be generally attributed to excessive pressure spikes due to not using some slower powders as intended or as becomes the recommendation?
Posted By: Shotgunjones Re: Why don't shotguns ring chambers? - 08/13/20 02:45 PM
Originally Posted By: craigd
It might be that these problems are not happening due to bad luck with normal pressures, these seem to be generally attributed to excessive pressure spikes due to not using some slower powders as intended or as becomes the recommendation?


It's happened with black, and that's plenty fast.

A report on the Shiloh forum indicates it happened with a hang-fire BP load and it took exactly one shot.

AA 5744 is a fast powder for a rifle.

Successful loads are made for the 45-70 using fast powders such as Unique also. Some guys go as slow as IMR 4064 and seem to do just fine.
Posted By: BrentD, Prof Re: Why don't shotguns ring chambers? - 08/13/20 02:53 PM
What gun on the Shiloh forum was this? I disremember.

In the FWIW department, schuetzen shooters routinely breech seat thousands upon thousands of loads with black powder and a gap behind the bullet. Nary a problem and excellent accuracy year after year, as their targets illustrate.

I know of no one that has been able to replicate Dell's results. Particularly the shooting straight up one.
Posted By: craigd Re: Why don't shotguns ring chambers? - 08/13/20 03:01 PM
Only opinions here Sj. I think unique is an outstanding powder, and a really nice option to have for nearly any cast bullet fiddling. I suspect you will want to try your new rifle way out at long range, and may look to other powders.

I would be a little hesitant to assume black powder is just dumped into a case and fired. Folks are using all manners of wadding, duplex loading and compression that might make the powder seem like a semisolid block. Maybe, start with something like the Lyman manual, then branch out as you become familiar?

edit to add Brent, most schuetzen shooters are using relative small bore rifles and exclusively smokeless powders, fast pistol type powders.
Posted By: crs Re: Why don't shotguns ring chambers? - 08/13/20 03:29 PM
Shotgun jones ;
Two comments:
1- 5744 is OK for low speed plinking loads in my 1886 riles (45-70 and 90). 4198 is good in my 45-70 DR giving an accurate 1590 fps load at 13,900 psi low pressure. A 300 grain .458 bullet at 1600 fps is plenty good for deer and hogs at 45-70 hunting ranges.
Serious DG loads are another matter entirely.

2. I have been shooting for several decades and never have "ringed" a rifle chamber or a revolver chamber. Therefore can not offer counsel on the subject.
Good luck and keep your powder dry.
Posted By: keith Re: Why don't shotguns ring chambers? - 08/13/20 06:02 PM
Originally Posted By: SKB
Backer rod is not flower arranging foam. Your ignorance is on full display once again.

Were you to be interested in learning instead of slinging mud, you might read Graham Wright's book "shooting the British Double rifle" as it covers the subject of back rod quite well.


I know full well that backer rod is not flower arranging foam Queen Stevie. I also have the third edition of Graeme (not Graham) Wright's book... and unlike you, I have this thing called "Reading Comprehension".

I even know that subjects of the Roman Empire were not Europeans, and know the difference between feather crotch black walnut and thin shell walnut... unlike you.

Here's a QUOTE made by your boyfriend BrentD in post # 577567

Originally Posted By: BrentD

I and a few friends have been loading bpcr cartridges with light loads of Unique, 4227, and similar powders, then pushing 3/8" of fine-pore floral foam over the powder until it crushes. This also holds the powder on the primer and creates a sizable amount of space to the lead bullet. Accuracy is greatly improved in most cases. No problems have been reported.


And there we have it... your ignorance on full display again, along with yet another shrill melt-down, all because you were consumed by an estrogen fueled rage over me criticizing your boyfriend.

No surprise there Queen Stevie!
Posted By: SKB Re: Why don't shotguns ring chambers? - 08/13/20 06:30 PM
Originally Posted By: keith

I even know that subjects of the Roman Empire were not Europeans



Well you just go ahead and re-write history as you see fit.

I think you will find that the vast majority of the subjects of the Western portion of the Roman Empire were indeed European.

Posted By: BrentD, Prof Re: Why don't shotguns ring chambers? - 08/13/20 06:34 PM
Originally Posted By: craigd
Only opinions here Sj. I think unique is an outstanding powder, and a really nice option to have for nearly any cast bullet fiddling. I suspect you will want to try your new rifle way out at long range, and may look to other powders.

I would be a little hesitant to assume black powder is just dumped into a case and fired. Folks are using all manners of wadding, duplex loading and compression that might make the powder seem like a semisolid block. Maybe, start with something like the Lyman manual, then branch out as you become familiar?

edit to add Brent, most schuetzen shooters are using relative small bore rifles and exclusively smokeless powders, fast pistol type powders.


Craigd
I'm not exactly sure what you are saying. But bp schuetzen is loaded without duplex, and typically involves drop tubing or compression or both and the calibers are generally larger than .32, with 38s being more common along with .40s and .45s (my personal favorite). Bullets are always heavy for bore. Again, air spaces between overpowder was and bullet exist without problem.
Posted By: keith Re: Why don't shotguns ring chambers? - 08/13/20 06:35 PM
Originally Posted by SKB
Originally Posted by keith
I even know that subjects of the Roman Empire were not Europeans

Well you just go ahead and re-write history as you see fit.

I think you will find that the vast majority of the subjects of the Western portion of the Roman Empire were indeed European.

Europe was not called "EUROPE" until the 8th century, well after the Roman Empire ended in 476 A.D.. Therefore, subjects of the Western Roman Empire were not Europeans. I've been patiently waiting to set the hook on that one, and all it took was a little twitch of the lure to get the brain-dead fish to bite.

He/she who does not learn from history is doomed to be a complete idiot, and you are a perfect example Queen Stevie. I guess you are all done with claiming I don't know the difference between flower foam and backer rod... and still in full coward estrogen melt-down mode. I love it!
Posted By: craigd Re: Why don't shotguns ring chambers? - 08/13/20 09:16 PM
Originally Posted By: BrentD
Originally Posted By: craigd
....edit to add Brent, most schuetzen shooters are using relative small bore rifles and exclusively smokeless powders, fast pistol type powders.


Craigd
I'm not exactly sure what you are saying. But bp schuetzen is loaded without duplex, and typically involves drop tubing or compression or both and the calibers are generally larger than .32, with 38s being more common along with .40s and .45s (my personal favorite). Bullets are always heavy for bore. Again, air spaces between overpowder was and bullet exist without problem.

Are you thinking of BP silhouette, not schuetzen? The only schuetzen I am familiar with is the ASSRA sanctioned 100 and 200 yard matches where the groove diameter tops out at .321 with a rare occasional exception.

I was referring to the big fixed load long range rifles, as you mentioned possibly .375’s, but more likely the .410s and .458s. It is not fun at all to breech seat using black powder. I haven’t done much of it, but the residue just forward of the case is a pain as it builds.
Posted By: BrentD, Prof Re: Why don't shotguns ring chambers? - 08/14/20 02:05 AM
No, I meant what I said. We shoot a lot of it in Iowa, especially the east coast, where Schuetzen has been around longer than any other shooting sport and we argue with Texas about the longest, continually operational Schuetzen club. We don't top out at .32, we start there and that is quite common where BP is used. We use smokeless too, but true to the sport, BP is always part of the game.

.375s do not, a long range rifle, make. They mostly suck at midrange too, and are rarely used in silhouette well (unless your name is Rick Moritz). Few shoot .40s at long range (and almost never .410s) and very, very rarely do they do well. Most of us shoot .45s, muzzle or breech.

If it is not fun to breach seat blackpowder, that's just your spin on it. For a lot of us it is a lot more fun because it is a lot more traditional and challenging. I've done it a lot. My first serious shooting sport was Schuetzen, though now I shoot mostly BPCR/BPTR and USIMLT Creedmoor wherever they are shot.
Posted By: craigd Re: Why don't shotguns ring chambers? - 08/14/20 03:00 AM
Fair enough.

Only curious, which traditional 45's cartridges do you folks shoot, breech seated, swiss butt plates, off hand?

I believe you, it would just be absolute torture to shoot a 'long for bore' 45-70, knowing you can not really down load black powder, and all at only 100 or 200 yard targets for score.

No fair mentioning muzzle loading, but that may be a bit different than pure breech seating, but again fair enough. I have felt a seater start to get inconsistent, never fired for score in competition, but I didn't care for what I percieved as inconsistency.

.408, .409, .410 take your pick, but I think 40 is a misnomer just as 45 is. In the long range matches that I am familiar with, the 38s and 40s are definitely well represted at long range, but the 45s are the default safe picks. Ouch, a well built 38-50RH sucks at mid range? You folks are a tough crowd.
Posted By: BrentD, Prof Re: Why don't shotguns ring chambers? - 08/14/20 12:06 PM
Mostly .45-70, but also .45-90 and .45-100. Most Schuetzen is benchrest these days, but there are always a couple offhand events. Most of my guns are BPCR legal, so no Swiss plates. I have a .38-55 Borchard in a Helm configuration, so that one has a hooked buttplate, which is very difficult to shoot off bench of course.

The .40s really are .400/.408 most of the time. .45s are .450/.458. Calling them by their groove diameters seems odd since at least I use land diameter bullets.

It is VERY rare to see a .40 at a long-range match. .38s, maybe one time I have seen one. I have a .38-72, which I would never use for long range.

You just aren't very familiar with long and midrange competition apparently. .40s only make a sizable dent in BPCR and then, it is still is second fiddle to .45s. .38s are way down the list at BPCR. Only one person has notable success with a.38-50 and that's Moritz. He has won the Championship twice or three times with it, but no one else can crack the top ten.
Posted By: HomelessjOe Re: Why don't shotguns ring chambers? - 08/14/20 12:27 PM
You know Brently I had you figured for a Shitzen....
Posted By: SKB Re: Why don't shotguns ring chambers? - 08/14/20 12:33 PM
Brent,
Do you know Jack Odor?
Posted By: BrentD, Prof Re: Why don't shotguns ring chambers? - 08/14/20 12:34 PM
Certainly. I know him fairly well. He grew up in Webster City Iowa, about 20 miles north of me.
Posted By: SKB Re: Why don't shotguns ring chambers? - 08/14/20 12:36 PM
Good guy, great shooter. I do a bit of work for Jack and have hunted with him. His house is like a tour through a B&C record book. The Elk he shot last year was so big they had to cut a larger entry way in the place to get the mount in. Small world.
Posted By: BrentD, Prof Re: Why don't shotguns ring chambers? - 08/14/20 12:47 PM
I would love to see his home. I know he hunts, but he is also a pretty serious butterfly collector. Definitely a great shot and an interesting guy. Did you do the smithing for his rifle sights? I wonder if his hunting rifles are set up like his target guns?

I usually see him ever year at Raton. But not this year of course.
Posted By: craigd Re: Why don't shotguns ring chambers? - 08/14/20 12:48 PM
Originally Posted By: BrentD
Mostly .45-70, but also .45-90 and .45-100. Most Schuetzen is benchrest these days, but there are always a couple offhand events. Most of my guns are BPCR legal, so no Swiss plates. I have a .38-55 Borchard in a Helm configuration, so that one has a hooked buttplate, which is very difficult to shoot off bench of course....

Since you mentioned historical connections, I believe if you look it up, you are not using the concept of Schuetzen in any traditional sense and are using it to descibe what it has morphed into for your region in modern times. I really don't mind being lectured about not knowing squat, but BPCR legal configurations are primarily intended for a different disciple.
Posted By: SKB Re: Why don't shotguns ring chambers? - 08/14/20 12:53 PM
No his off eye sights were built by another. I have bent shotguns, done finish work on rifles for him and am currently building Jack custom scope bases for a Hagn rifle. He shoots scopes set up for his right eye for hunting so very different from his target guns.

He has a full collection of every single North American Duck you can legally shoot mounted as well.
Posted By: BrentD, Prof Re: Why don't shotguns ring chambers? - 08/14/20 12:55 PM
Originally Posted By: craigd
Originally Posted By: BrentD
Mostly .45-70, but also .45-90 and .45-100. Most Schuetzen is benchrest these days, but there are always a couple offhand events. Most of my guns are BPCR legal, so no Swiss plates. I have a .38-55 Borchard in a Helm configuration, so that one has a hooked buttplate, which is very difficult to shoot off bench of course....

Since you mentioned historical connections, I believe if you look it up, you are not using the concept of Schuetzen in any traditional sense and are using it to descibe what it has morphed into for your region in modern times. I really don't mind being lectured about not knowing squat, but BPCR legal configurations are primarily intended for a different disciple.


I'm using the "concept" of Schuetzen as it exists today in ASSRA and ISSRA matches, which I used to shoot quite a bit. I quit most of that, however for BPCR/BPTR and USIMLT.

Yes, BPCR and Schuetzen are different "disciple". Many of us still use the same rifles in both venues because we can and want to. Were I to shoot Schuetzen this weekend at Steamboat, I would almost certainly use my .45-70 BPCR rifle simply because it is the most accurate rifle I own off a bench and I need all the offhand shooting I can get with it because it is difficult to shoot offhand. Instead, however, I'll spend my weekend digging out from the derecho.

So, craigd, do you shoot organized competitions of any type seriously? Which ones?
Posted By: FelixD Re: Why don't shotguns ring chambers? - 08/14/20 01:35 PM
Why don’t shotgun chambers ring? Without an obstruction there is less resistance in shotgun ejecta than in a rifle. Lower operating pressure on ignition.
Posted By: craigd Re: Why don't shotguns ring chambers? - 08/14/20 01:53 PM
Thanks for catching the typo Brent, I appreciate it.
Posted By: BrentD, Prof Re: Why don't shotguns ring chambers? - 08/14/20 02:21 PM
Originally Posted By: craigd
Thanks for catching the typo Brent, I appreciate it.


I make plenty of typos too. But I just thought that 1 was kind of interesting and humorous.
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