Mumbles Posted February 4, 2013 Share Posted February 4, 2013 Mumbles...you and I agree on reason for hard grains. Still can't quite get to the same burn rate as commercial BP. Had to use 35 gns to lift a 2 1/2" round shell. OK though since I make my own in large quantity. Maybe pauwlinia would help? Made another 5# w/dextrin 5% and am going to tumble the 2 and 3f grains a bit.... Do you actually mean 35 grams? I was confused whether you mean grams or grains by "gns". I have seen gn used as an abbreviation for grain, as opposed to the more common gr. 35 grains would be some very hot BP for that size shell. There are a ton of variables at work in BP. The two biggest that control raw burn speed are charcoal source and milling time in my opinion. There are probably at least a dozen other factors that will each play a smaller role, but can combine to make a difference. From raw burn speed you can also control actual burn speed based on grain size, granulation method, etc. Remember, BP can be too hot in some instances too. Link to comment Share on other sites More sharing options...
Blackthumb Posted February 6, 2013 Author Share Posted February 6, 2013 Mumbles...it was grams.....redried it and it takes about 30 grams to adequately launch a 45 gram shell....going to try different charcoal Link to comment Share on other sites More sharing options...
dynomike1 Posted February 6, 2013 Share Posted February 6, 2013 If by some reason i get a batch of slower BP i use it for burst. I test every batch i make. Link to comment Share on other sites More sharing options...
pyrojig Posted February 18, 2013 Share Posted February 18, 2013 Slower bp has its place in pyro. It is good for coreburners, fountains, hummers, star comps, and even black match( if your not after explosive fast match). I too use the paulownia for my bp, and using the tips that mumbles speaks of, I get faster than commercial. My willow too out performs the commercial grades. I find that the milling with a efficient mill, and the use of good/ reactive charcoal is a big factor. I milled a batch of mesquite charcoal bp and used the same techniques of my fast stuff. It sucked in comparison( way under commercial), it goes to show the importance of selecting good charcoals. Link to comment Share on other sites More sharing options...
Shadowcat1969 Posted February 19, 2013 Share Posted February 19, 2013 I too have finally experienced the good charcoal effect! I was using mixed hardwood commercial airfloat and having very poor results. I tested a batch of BP milled over 48 hours, corned, using an inert 54 gram 2 inch spherical shell. I got about 150 feet and it was pretty slow. I recently bought a box of Paulownia charcoal from Algenco, and made my first batch of BP with that, milled for about 6 hours, corned and I tried the same test shell with 5 grams and I couldn't track it, it left the mortar so fast. Took over 10 seconds to return to earth. I then tried with 3 grams and it took almost 8 seconds, again I couldn't find it in the sky. I'd definitely recommend charcoal made with "faster" woods. And Algenco's charcoal kicks ass! Link to comment Share on other sites More sharing options...
Nessalco Posted February 20, 2013 Share Posted February 20, 2013 Since I discovered the TLUD process, I've been making all my own charcoal. Super easy. I haven't had an opportunity to do much testing yet (six inches of snow fell overnight, adding to what's already here), but will be using baseballs in a 3" mortar. I'll be testing black willow, aspen, red cedar, and wild grape charcoals. I also have a few pounds of red oak charcoal for gold sparks, but I'm not going to waste it on BP. Kevin Link to comment Share on other sites More sharing options...
pyrojig Posted February 20, 2013 Share Posted February 20, 2013 Its funny, and I would have never expected it but, some oak can make very powerful bp. I read this in the pyrotechnica artile # 11 I believe . It showed a list of all charcoals and their power, speed, and spollete burn times. Oak ranked in the top 5 Link to comment Share on other sites More sharing options...
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