compressing black powder

[martinibelgian]

Mike,
One of the issues with compressing the powder with the bullet is that you're bumping up the bullet diameter - and probably quite a bit. So that nice .459 bullet might well be .463+ after compression. A caliper will tell you a lot here. Which could lead to chambering issues, leading, indifferent accuracy,...

[MikeA]

Martinibelgian, hey,
I can understand that. I haven't done any measurements of the case to if simple math could tell the difference but I do cast a super hard bullet. 70% lead, 30% antimony. I'll have to try my new compression die. But responding to accuracy, I have had no leading, extremely accurate but I seem to have better results not chambering the bullet to the rifling. I have had worse results from that. I'll definitely measure a case. Quick question, would you know where to buy a 45/110 barrel

[yulzari]

Slightly OT but may be of interest.

I investigated solid black powder rods for my Mannlicher M1888. The idea was being experimented with by the military in various countries at the end of the 1880s with the aim of getting enough black powder into the 'modern' brass cartridges to allow velocities permitting smaller bores and flatter trajectories and using jacketed bullets to clear fouling. With granulated black powder and lead bullets barrel fouling limited bore size to about 10.5mm to 9.5mm even with paper patched bullets. In Germany 9.3mm, 11mm in Austro-Hungary and 10.4mm in the Enfield Martini. In the Lee Metford the rod was solid with a hole through the middle so the primer flash burned outwards. The Swiss used the same but skipped this stage in production and went straight for a smokeless powder. The Mannlicher M1888 also had a solid rod but surrounded by powder so that the flash burned inwards. In all cases the rods were made by forcing a wet (water? alcohol?) black powder paste into a metal die, dropping the rod into the case and then forming the neck.

Trials of compressing dry powder found that the powder nearest the compressing rod was formed almost solid and the rest was far looser. Compressing in stages (ie putting in some powder, compressing, adding some more, compressing that and so forth) was the most effective but prevented effective flash propagation as the compressed powder had to burn from the rear end. That was solved by a hole (either full length or part length) up the middle, or leaving an annular gap around the rod. However this meant that the extra black powder that could be forced into the cases was lost with the loss of powder in making the hole. Pressures markedly (I have no data) increased with these degrees of compression. I suspect that the end benefit for the few eventual users of solid black powder cartridges was the controlled rate of burn. Careful drop tubing and compression can get in almost as much as the service solid rod charges.

A word of warning. I got the full 62 grains of the service charge of black powder into my Mannlicher M1888 cases but the powder was so fine that the speed of burn meant that primers became flattened and the recoil was sharp so I have backed off to a full case of coarse powder which is 85% of the weight with a bullet also 85% of the service weight. Works fine with the sights set for 200 paces firing at 100 metres. Cleaning the 8mm bore suggests that fouling would become problematical after a few clips and they were withdrawn within 2 years to convert to semi smokeless.