Recently I met up with an old college buddy. We were reminiscing about the "good ole days". Our discussion reminded me of something. Now he was one of those folks that liked to roll his own "cigarettes". He had a unique way of doing this. What he would do was take a new soda straw that was wrapped in paper, cut off one end and then pour "tobacco" down the straw. He would then withdraw the straw leaving the "tobacco" inside the paper tube. Finally, he would cut the paper and twist the end - presto!

I then got the idea: Why not do the same thing with smokeless powder and produce paper-encased reduced loads for cast bullets? These straws are everywhere for the taking and come in many diameters/lengths that would accommodate straight and bottle-neck cases. You could make the paper cartridge length long enough to extend from the base to the neck to prevent it from moving around. This would seem to solve the problem of flash over and make for very consistent loads. The primer flash front should easily penetrate the thin paper and consume it totally. At the factory, the paper is sealed by roller crimping. I think you could seal the cut ends with the grooved jaws of vise-grip piers.

What say you?

Bob

As i understand it, the primer pressure from firing pushs the powder against the base of the bullet, no filler needed. See primer #41 test in the 5.56mm. link

I read the study. It was conducted with near case capacity loads of all propellant or propellant/inert mixes. It reports that upon primer ignition the propellant mass moves forward and the flame front penetrates about 33% of the propellant column before the projectile moves.

This does not address super sub-capacity loads associated with shooting cast bullets in centerfire rifle cases. That's why reloaders
use fillers to keep the small charges against the primer. This is suggested to reduce erratic ignition and possible flash-over pressure. spikes. My inner paper charge cartridge would provide a consistent positioning of the charge column that might prevent those problems.

I would wonder if the "straw paper" would be combustible enough. Might be OK for cigarettes, but maybe not for your paper load idea. Unburned paper could easily cause a bore obstruction. Anyway, roll some up and try 'em and lets us know the results.

craigster,

That paper is very fragile just like cigarette paper. It should literally disintegrate when the primer fires. I would try it but my stuff is packed up in a move right now. When I do it will be 50 ft away with a string though(i.e. I wouldn't bet my life on it)! Maybe I could poke some holes in the paper to let the flame in.

Hell, maybe I'll try it myself. I'll let you know.

quote:

Originally posted by Bobster:
...This is suggested to reduce erratic ignition and possible flash-over pressure. spikes. My inner paper charge cartridge would provide a consistent positioning of the charge column that might prevent those problems.

Hey Bob, As I mentally picture the Powder filled paper Tube inside the Case, I notice a good bit of "empty space surrounding the Tube". As the mental image Fires, it appears the Tube helps promote Flashover, by allowing the Primer Flame to reach alongside the Tube.

What do you see different in your mental image that I'm apparently missing?
-----

I could be wrong, but I seem to remember Powder filled Paper Tubes being used in some of the old Breech Loaders of by-gone eras. They inserted a Lubed Lead Bullet, stuck in the Tube and closed the Breech. A small access port allowed the Burning Rope to ignite the charge as it was lowered to the port. But, that was before my time. Maybe Bartsche and Craigster used them.

quote:

Originally posted by Hot Core:

quote:

Originally posted by Bobster:
...This is suggested to reduce erratic ignition and possible flash-over pressure. spikes. My inner paper charge cartridge would provide a consistent positioning of the charge column that might prevent those problems.

Hey Bob, As I mentally picture the Powder filled paper Tube inside the Case, I notice a good bit of "empty space surrounding the Tube". As the mental image Fires, it appears the Tube helps promote Flashover, by allowing the Primer Flame to reach alongside the Tube.

What do you see different in your mental image that I'm apparently missing?
-----

I could be wrong, but I seem to remember Powder filled Paper Tubes being used in some of the old Breech Loaders of by-gone eras. They inserted a Lubed Lead Bullet, stuck in the Tube and closed the Breech. A small access port allowed the Burning Rope to ignite the charge as it was lowered to the port. But, that was before my time. Maybe Bartsche and Craigster used them.

In a flash over situation my mental picture is a reduced load spread out over the side of the case from the web to the taper with the case laying horizontal. This exposes nearly 100% of the charge to spontaneous ignition. You are correct in envisioning more surface area available with the internal paper cartridge. However, I think it would be significantly less and probably no more than the load pushed against the base w/dacron or other filler. The flame front still has to penetrate the column end to end. I guess I'm visualizing a sectional density thing. Think about cordite. It is composed of long, thin strands of propellant that extend from the case base to the bullet base, exposing a large amount of surface area. It apparently functioned quite well.

The advantage I'm seeing is that no matter how hard you jostle the round, the charge won't displace. Even w/dacron, if you drop the round the charge would likely shift. This would be a real advantage for the person that wanted to hunt with cast bullets, but perhaps not so much for the target shooter.

Oh yes, paper cartridges are certainly not new. The famous 1858/63 Sharps carbine/rifle used a paper cartridge filled w/black powder tied to the base of a .64 cal lead slug. When the lever was raised it chopped off the end and exposed the powder to the primer.