Ringing your chamber with and without filler

[KirkD]

Smokeless powder in black powder cartridges (such as the 45-70 and the 38-55) leaves a lot of air space and can produce a larger extreme spread in velocity due to poweder position. Some sort of filler can help solve this problem. I was reading about some interesting research done by Charlie Dell. Apparently, he could ring a chamber at will with certain normal loads and in certain cartridges by simply pointing the rifle straight up and pulling the trigger. The phenomenon seemed to be caused by the powder all being completely back against the primer and perfectly flat across the base, since it was pointed straight up. The result was a pressure wave that ringed the chamber around where the base of the bullet was. Some have reported a ring at the same location when certain types of filler were used, particularly with straight walled cartridges.

It is hard to know for sure without testing, which I do not plan to do, but it may be the case that if a filler both kept the powder perfectly back against the primer AND was fluffy enough to permit a shock wave to hit the base of the bullet, that the same ring could be produced with the rifle in a normal horizontal shooting position. Some have suggested to leave a space between the base of the filler and the powder so that the powder sloped when being fired.

Here's my thinking: Cotton, dacron and kapok can both keep the powder nicely and flatly against the primer, and be fluffy enough to possibly permit a shock wave to ring the chamber exactly as might happen if no filler was used at all but the gun pointed straight up. Polyfiller does not do both. It holds the powder pack perfectly, but I think the polyfill dampens out the shock wave as it compresses, which is why it seems to be safe (though I've never used it). Toilet paper does neither, at least not the way I've used it for thousands of rounds. It sort of holds the powder back nicely, but not perfectly, as some powder can easily work forward a bit into the butt ends of the loosely rolled and folded TP.

I could not see how adding a loose, low density filler into the load could increase pressure in such a way as to ring a chamber, but Charlie Dell's work makes sense to me and maybe turned on a light.

Bottom Line: With certain powders and certain cartridges, it may be possible to ring the chamber by either using no filler and pointing the gun straight up or by using certain types of filler, re-creating the same powder position in a horizontal orientation. The bottom line is to avoid any type of filler that might recreate both the powder position and the shock wave that pointing the gun straight up could cause.

Conclusion: It seems to me that toilet paper loosely rolled and folded is safe, since it does not perfectly position the powder against the rear primer. It also seems to me that polyfill would be safe because although it does perfectly position the powder against the primer, it compresses and dampens out the shock wave. The danger may be in cotton, kapok and dacron with certain loads. I know that Sherman Bell has done strain gauge testing at the case neck with all these kinds of filler and found that the pressure was entirely within the safe zone, but who knows how it would work with different powders, especially faster ones. I would think that slower powders will be less likely to create the nice shock wave.

Personal Recommendation: After reading about Charlie Dell's work and thinking on this, I'm inclined to think that we should not use cotton, dacron, or kapok as filler. If filler is required, I'm feeling that toilet paper, loosely rolled and folded or polyfill should be fine. I've used toilet paper in a few thousand rounds and in different calibers such as 38-55, 45-90, 45-70 and 44-40 with never the faintest hint of a problem. I have been using cotton filler more recently, but after reading about what Charlie Dell found out, I'm swearing off cotton filler. I admit I'm erring on the side of caution, and a lot of fellows use this with no problem at all, but I think Charlie Dell's findings make a lot of sense, at least to me. No more cotton filler for me; it positions the powder too perfectly against the back of the case to risk re-creating the effects of a non-filler, vertical shot.

Alternative: With 5744, I have found a Winchester Magnum primer gives me the same velocity in my 38-55, but a lower extreme spread. So it makes a filler unnecessary.

[milton]

Thank you very much for a very beneficial post.Could this be interpolated into revolver data and problems with powder position?

[KirkD]

Pistol cartridges are usually short enough for their width that I've never really felt the need for filler in them. The question might be whether shooting straight up would ring a pistol chamber. I don't know, but since shooting straight up is a bad idea for other reasons, it is only re-creating a straight up powder position that we would need to avoid. Also, pistols tend to be loaded with fairly fast powders, which would be a bad combination with fillers. The only application of fillers that I've used is really with black powder rifle cartridges and smokeless powder.

[Griff]

With the exception of the 45Colt and small charges of "fast" powders. In my playing around (not to be confused with 'experimentin'), with light charges in the 45Colt, low to evem moderate density loads can yield widely different based on powder position. These were from my 20" barreled Rossi '92. Just levering in a cartrdge from the magazine to the chamber yielded 768fps with a 200gr LRN and 5.5 grains of RedDot. Holding the rifle muzzle up and slowly lowering it raised velocity to 790fps, and a muzzle down before firing dropped velocity to 722fps. Alternately, just the same weight charge of Clays from the 24" 1873 and a 225 grain bullet averaged 836fps with a SD of 13.03.

I might even postulate that such an event could have been the catalyst for a catastrophic failure when lighter than suggested loads are fired in handguns. Recoil might have caused the firearm to recoil upward, forcing powder back against the primer, then repeated with successive shots... enough of these could have been enough to strain the limits of the steel. I know from my horseshoein' days, that one blow of a hammer seldom bends steel. But, repeated blows will certainly do so.

[KirkD]

I've not much experience with pistol cartridges other than 44 Russian, 45 Schofield and 45 ACP. In my 45 Schofield, I use 5744 which fills most of the case and gives a pretty low E.S. I wonder what Unique would do re. powder position and E.S.

[w30wcf]

Kirk,
I think Charlie Dell's tests are interesting,...in my opinion, a bit flawed because he used bullseye powder in a 45-70 which is much too fast for use under the under the heavy bullets in the charge weights he used.

I do believe a hard card wad over a powder charge certainly has the ability to ring a chamber when it collides with the base of a bullet but slower burning powders like 4227+ with either a tuft of cotton, dacron, t.p. there is likely no chance since they are flexible and not hard.

Check this sectioned W.R.A. CO. .45-70 Short Range cartridge. DuPont No. 2 has a burning rate similar to 4227. In this case the bullet wheighs 225 grs rather than the heavier 400+ gr bullets and that is a cushion wad, not a hard card wad. Obviously if Winchester thought this would be an issue, they would not have loaded that ammunition that way.



A simple paper disc punched from copy or target paper works just fine in a straight walled cartridge case to hold the powder in position.

PSB (Polyethylene Shot Buffer) does work well in some applications (no fast brning powder!!) since it fills the space between the powder and the bullet completely.

w30wcf

[KirkD]

That is fascinating info, John. Thanks for posting those photos. Very interesting. I didn't realize Dell was doing his tests with Bullseye!

[cas]

Unless they stopped loading them that way because they found out they were ringing chambers.

[Sixgun]

Unless they stopped loading them that way because they found out they were ringing chambers.

Yea Cas, I was just thinking the same thing. And................the rifles they were shooting them in were only worth $15 then, not 5K today.

I believe we go through this filler thingy from time to time. Just talk to anyone thats been loading these old guns for the last 40 years or more, (like me) and you will see that they have read over the years about the dangers of fillers. Yea, very rare, but............

I was so happy when 5744 came out and it's easy ignition. Before that it was 4759 or 4198 but I always got wide variations with those powders.......in cold weather.--------------6

[KirkD]

Yes, 5744 is my go-to powder for all my black powder cartridges which, at the moment, is 32-20, 44-40, 45 Schofield, 38-55 and 45-70.

[AJMD429]

I might even postulate that such an event could have been the catalyst for a catastrophic failure when lighter than suggested loads are fired in handguns. Recoil might have caused the firearm to recoil upward, forcing powder back against the primer, then repeated with successive shots... enough of these could have been enough to strain the limits of the steel. I know from my horseshoein' days, that one blow of a hammer seldom bends steel. But, repeated blows will certainly do so.

It really IS disturbing that there is so much velocity change caused by changing the position the gun is held in immediately before firing, when using some powders and loads.

It seems like a powder that nearly-fills the case is the way to go whenever possible, not only for that reason, but because a double-charge is also impossible.

[Nath]

How about ramming more T paper in and use a hand rammer,,,,no?

N.

[w30wcf]

Unless they stopped loading them that way because they found out they were ringing chambers.

cas,
While that is possible, the fact that the round came from a box dated July, 1906 and by then, the 45-70 "Short Range" smokeless cartridge had been in exsistence for about 10 years. Of course, perhaps the over powder wad was not in the original cartridges........

I have also found the same type of over powder wad in some early UMC .45 Colt cartridges.

w30wcf

[cas]

All depends on how you look at it I suppose. Information flow is the speed of light now days, but a 100 years ago how many problems would it take, and how long would it take for enough those problems to occur, and then how long before enough feed back made it back to the company to realize thee was a problem? Then to make a change?

Reminds me of a few cars/trucks I've known that SHOULD have been recalled, but the manufacturer just played dumb and waited it out hoping for the best.

[AJMD429]

Reminds me of a few cars/trucks I've known that SHOULD have been recalled, but the manufacturer just played dumb and waited it out hoping for the best.

Sometimes recalling, or even just 'improving', a product, will result in a deluge of lawsuits as it is an implicit admission that you knew there was a problem. One of many ways the modern version of being a 'lawyer' has perverted real justice and made so many things worse instead of better.

[rogn]

Quite a while back I was doing some experimentation with a Taurus 66. This is not the same I know, but I was doing some fringy stuff, The chamber, cylinder, barrel and forcing cone dimensions were all in discord and I wound up using "grex" or other plastic buffers. I used a Lee dipper whose volume slightly overfilled the remaining space. Most of the loads were warm side with faster burning powders. I suspect the case being filled w/ no air space negated all the shock wave potential. I'll mention also, that if you have a revolver that wont shoot cast real well, try this system; reduce charges a bit to start. They shot very, very well. Without you couldnt hit any part of a barn, no matter where you stood.