Thread: Ulrich Bretscher's SMOKELESS BLACK POWDER & HANDGONNE web page. Re-found!

Originally Posted by Carlsen Highway

I can feel myself moving exponentially closer to blowing myself up.

Just don't take Port Chalmers with you!

correct potassium nitrate...... and no your local pharmacy or fertilizer store WONT have either sulphur or salt petre but good news is they are for sale on trademe...and look to be finely ground....

Have seen the components ground up in a old vitamizer (spelling), the older version of these new smoothie makers, and then combined. Seemed to work OK..... was for a pack howitzer.....and it went bang.

Garden centre's are a good source of potassium nitrate (stump rotter) and flour of sulphur (organic fungicide) Flour of sulphur needs no grinding either but the nitrate does.

Garden centre.....now why didn't I try there LOL

Originally Posted by Micky Duck

Garden centre.....now why didn't I try there LOL

Amateur...

Originally Posted by Marty Henry

Garden centre's are a good source of potassium nitrate (stump rotter) and flour of sulphur (organic fungicide) Flour of sulphur needs no grinding either but the nitrate does.

There is a better way.... NOt that I know from personal experience.
The stump rotter is sold in small jars for lots of dosh.
Try a hydroponics store, should get a big sack for bugger all.

Originally Posted by 40mm

There is a better way.... NOt that I know from personal experience.
The stump rotter is sold in small jars for lots of dosh.
Try a hydroponics store, should get a big sack for bugger all.

Expert level.

Originally Posted by 40mm

There is a better way.... NOt that I know from personal experience.
The stump rotter is sold in small jars for lots of dosh.
Try a hydroponics store, should get a big sack for bugger all.

Just make sure it is potassium nitrate, not sodium nitrate. Sodium nitrate is hydrophilic and makes your gunpowder moist just through being exposed to atmospheric humidity.

A sackful... are you planning on powering your 40mm au natural?

be interesting to see how you get on. I have noticed potassium nitrate disappearing from some of the traditional sources.

Ask your local hunting/gun shop to get it in. It's also used for making sausages!

A research link.

https://www.researchgate.net/publica...s_compositions

And abstract in Chinglish, last sentence at odds with Ulrich's findings, but maybe they did not test in a gun chamber:

"Gaseous phase products and thermodynamic parameters of various charcoal/KNO3 compositions are calculated using the least free-energy principle. From the point of view of reaction kinetics theory, simulation results are analyzed and ratios of compositions optimized. Taking ratio of gas products, force of the powder and temperature of explosion as target functions, low corrosion and environmental-friendly sulfur-free black powders were designed and their thermodynamic properties improved. The physical, chemical and output properties of the optimized compositions compared with normal black powder. Results show that the sulfur-free black powder is more sensitive to flame, and insensitive to impact and electrostatics. The output power is also considerably higher than the normal composition."

bumpity bumpity

Hmmm - farken great thread resurrection, just added another high priority project to my lockdown list, now to scrounge some saltpetre

Originally Posted by Tentman

Hmmm - farken great thread resurrection, just added another high priority project to my lockdown list, now to scrounge some saltpetre

The extent you have pre-pulverised the charcoal is critical for having good powder. It determines how intimately the saltpetre crystals are associated with the charcoal. Basically, the better ground the charcoal the larger its surface area onto which saltpetre crystallises when the solution cools! Using the wet method/CIA method/Mickey Duck method, you don't grind the saltpetre - this gets dissolved and then recrystallises onto the charcoal, hence the focus on as fine as possible charcoal.

Tentman, where in Invercargill are you going to scrounge KNO3 in a lockdown situation?

I've requested a copy of that academic paper linked in my last post, see if something comes through. If anyone is a member of Researchgate ( @stug ?) they may be able to help here. Looks like it's got some info that needs to be added to this thread.