Powder burn rate

[Bunk Stagnerg]

Gentlemen,
Well I reckon I have to fess up  about my mixing powders when loading experiment.
The percussion  Sharps has a very long and circuitous fire path which takes two ninety degree turns.
In an attempt to use Black MZ in a paper cartridge there was simply not enough heat to ignite it.
So, clever fellow that I am, a very small amount of FFFg Gunpowder was placed in the base of the cartridge and the BMZ finished the charge.
Excellent ignition was the result.
Does this count as one of those "Hold my beer Bubba and watch this" moments?
Your thoughts
Load 'em heavy boys
They air a'comin'
and that is a fact
Bunk

[greyhawk]

But . . . . It "IS" luck.  right up until the day it isn't.  I'll reiterate.  Because you have gotten away with something STUPID (even for 25 years), doesn't mean you continue something STUPID.  Nor should you recommend the stupid act to others.  All it takes is one mistake to put it all inna toilette.

As an  Itty Bitty bit of information, the only thing retaining the Firing Pin Extension together in the older Brass Frame rifles is a tiny little cross-pin.  When it all goes inna toilette, that itty bitty pin will sheer.  Then the only thing to stop the Extension Rod as it exits the rifle . . . . is the shooters face and eye.  Think about that for a second.  There is NO justification for STUPID.

Stay Safe Out There
People can be Hazardous to Your Health

Well ifn we had the gear (we dont) to do a pressure test we could make a bet on that and I reckon I would win it - he's certinly not showing any advance on the chronograph over a full load of better quality black powder.
But then you blokes reckon I'm stoopid rollin me own smoke too
 

[Coffinmaker]

Hi Bunk 

My thought is:  A Duplex loading is a Duplex loading.  It makes me nervous regardless of the components.  The stored energy potential of 3f BP and Black MZ is nearly identical.  Perhaps no hazard.  I don't know enough to make a judgement.

The stored energy potential of Smokeless as compared to BP is often "off the chart."  I do know enough about that comparison to know mixing Smokeless and BP is not so Bueno.  I also know enough about smokeless to know there are smokeless combinations that will absolutely destroy modern guns.  I haven't been present to witness the event, but I have seen the resulting pieces.  At least the pieces that could be found.

Some things by their very nature are dangerous.  I don't think there is a powder manufacturer that hasn't had a plant explosion.  Whether BP or the more modern evolutions of "smokeless" propellants.  I am just not one to recommend taunting Murphy.

Stay Safe out There

[Bunk Stagnerg]

Be advised that when I do occasionally load that fad smokessomewhatless powder I research carefully and use manufacturers loading data compared with more that one source. Typos do happen and high energy mistakes result in really bad noisy things happening.

Load 'em heavy boys
They air a'comin'
no foolin'
Bunk

[Dirty Dick]

  Back in the day it was common practice to load a small priming charge of smokeless then the rest of the case with BP. There were even powder measures with two hoppers, one for BP and one for smokeless. SR 4759 powder was popular for this. This was said to eliminate BP fowling in the barrel.

Taken to an extreme the early load data for .454 Casull listed 2grs Bullseye first, then 2400 main charge then another 2 grs Bullseye on top! Light powder compression to prevent mixing.As well as other variations.