psymon Posted April 20, 2006 Posted April 20, 2006 Procedure for loading this mortar is as you say. I weigh the shell and then weigh out 1/3rd in BP. The mesh size is about 12 upwards. Then dump the BP in the mortar followed by a very tight fitting shell.I shall try to make the shell a little smaller by adding less pasting around it. Hopefully I wont deafen myself or the neighbours. I'll post the results...
Pretty green flame Posted April 20, 2006 Posted April 20, 2006 Procedure for loading this mortar is as you say. I weigh the shell and then weigh out 1/3rd in BP. The mesh size is about 12 upwards. Then dump the BP in the mortar followed by a very tight fitting shell.I shall try to make the shell a little smaller by adding less pasting around it. Hopefully I wont deafen myself or the neighbours. I'll post the results... Wow, 1/3rd for the lift. How much does your shell weigh ?
psymon Posted April 20, 2006 Posted April 20, 2006 Shell is around 30g. I add about 10g of lift. I used to add 1/4 the weight of shell as most tutorials say but I wasnt happy with the height so I increased the weight of the lift to get a bit higher. I granulate it by passing moist BP through a 12 mesh sieve.
Pretty green flame Posted April 20, 2006 Posted April 20, 2006 Shell is around 30g. I add about 10g of lift. I used to add 1/4 the weight of shell as most tutorials say but I wasnt happy with the height so I increased the weight of the lift to get a bit higher. I granulate it by passing moist BP through a 12 mesh sieve. OK, i really don't know the quality of your lift but i use 1/10 of the shells weight in lift. So around 3 grams for the shell you have. I think we found the reason for your defening lifts.
dragonman586 Posted April 20, 2006 Posted April 20, 2006 Psymon does that ratio of BP work better for you. Have you tried 75% KNO3, 10% S, and 15%Charcoal? If not try it, Bind it with like 10% of total weight in dextrin and then moisten and pass through a sieve.
Pretty green flame Posted April 20, 2006 Posted April 20, 2006 Psymon does that ratio of BP work better for you. Have you tried 75% KNO3, 10% S, and 15%Charcoal? If not try it, Bind it with like 10% of total weight in dextrin and then moisten and pass through a sieve. Dragonman, dextrin is a fire retardant if not incorporated in the mix well enough and even if it was, 10% would definatly slow down your BP by quite a lot. 3-5% should be enough for granulation.
Mumbles Posted April 20, 2006 Posted April 20, 2006 The ratio he posted is a lift specific formula. It is supposed to be better than 75-15-10, but I've never tried. Anyway, smaller shells need more lift. 1/3 or 1/4 does not seem unreasonable in the least to be for film canister shells. The amount used of course depends on quality of the lift.
TheSidewinder Posted April 21, 2006 Posted April 21, 2006 Breech-fired shells produce inherently more bang than ones that are quick-matched. The clearance is the issue. I have some 2-inch ID mortars and 1-15/16 inch plastic cans (designed to be breech-fired) that, as you can see, have *NO* clearance for top-matching. You cannot possibly quickmatch them like a conventional shell. They wouldn't fit in the tube. And when these shells lift, they REALLY go boom. If I use a "standard" plastic can or ball, with enough space to run quickmatch to it, it produces the dull thump most people know. Top-firing means much more clearance in the tube, much more gas blow-by, and much less noise. I verified this last year when I shot all 3 types out my mortars. That said, you SHOULD be able to use considerably less powder, and still get good lift height, using breech-firing.
dragonman586 Posted April 21, 2006 Posted April 21, 2006 I used to do 6 grams for a 7/8" ball shell when I was breech fireing. I had pasted it soo much that it fit snugly into the tube. It would just give a pathetic woosh and fly a depressing height. Now I use a lift cup I'm making it out with somewhere between 2.5-3 g of lift and it flies High with a nice boom. Meaning that breech firing sucks (well atleast in my case. )
weknowpyro Posted April 24, 2006 Posted April 24, 2006 Im going to be making a small cylindar shell and am using dowel as end caps wht should use for break becase i think bp will only blow out the end caps.
Pretty green flame Posted April 24, 2006 Posted April 24, 2006 Im going to be making a small cylindar shell and am using dowel as end caps wht should use for break becase i think bp will only blow out the end caps. Whistle or flash should be used if you have access to the chems needed for this. Otherwise finely granulated BP should work if you spike the shell. What Dia. is the shell.
weknowpyro Posted April 24, 2006 Posted April 24, 2006 About 1/2" these really are very small. I will probably use flash in the middle surrorned it with stars and bp would this ignite all the stars?
Pretty green flame Posted April 24, 2006 Posted April 24, 2006 About 1/2" these really are very small. I will probably use flash in the middle surrorned it with stars and bp would this ignite all the stars? 1/2" ones really are very small. I would suggest you step up to a little "bigger" stuff. 1" ones provide plenty of fun. Another option you might want to consider are cup sets. They are sold in sizes 3/4" and 1", the chinese use cup sets for their cake inserts, atleast where i live, and they are VERY loud and have good big breaks for such small inserts.
weknowpyro Posted April 24, 2006 Posted April 24, 2006 I have searched for these 'cup sets' but find nothing usful u got any pics?The problem is i don't have a bigger mortar so i will have to buy some, well i do but it don't fight my dowel and ideas.Its because i want to start with cylindar shells before round shells.
Douchermann Posted April 24, 2006 Posted April 24, 2006 Here ya go, 1" http://www.cannonfuse.com/scripts/prodView.asp?idproduct=818
weknowpyro Posted April 24, 2006 Posted April 24, 2006 Cheers i will probably buy some take some time to come over to england though. I think i will still go ahead this weekend and make that small one just to gte used to making them.
Pretty green flame Posted April 24, 2006 Posted April 24, 2006 Cheers i will probably buy some take some time to come over to england though. I think i will still go ahead this weekend and make that small one just to gte used to making them. Cannonfuse no longer ships outside the US, yes even paper/plastic products can not be shipped. You can buy them from pyrocreations, they ship outside the US and they have been very helpfull with my enquires. http://pyrocreations.com/miscellaneous
weknowpyro Posted April 24, 2006 Posted April 24, 2006 Yea now me and my mate are using a toilet roll tube for the shell and are using this post pack cardboard tube as the mortar. Should be ok the bog roll tube is about 1cm thinner than the mortar but after spiking and wrapping in craft paper it should fit. what do you think?
Mumbles Posted April 24, 2006 Posted April 24, 2006 After pasting and spiking a TP shell, the shells were always too big for me to fit in 2" ID tubes. a 2 1/8" or 2 1/4" ID would be much better.
dragonman586 Posted April 25, 2006 Posted April 25, 2006 Correct me if I'm wrong but don't you need to bury those postal tubes if you want to use them ans mortars?
Douchermann Posted April 25, 2006 Posted April 25, 2006 Well it all depends. There are various types of postal tubes. Last 4th of july my mortar tube ripped itself off the base I made for it, so I found some old postal tube that had like a 1/2" thick wall. At least I think it was postal tube. At that size you could probably get it to support a building.
psymon Posted April 25, 2006 Posted April 25, 2006 Recorded my 35mm flim can shell with 4 blue stars last night. Here is the video, I should have done it when it was a bit darker. Sorry no sound with my camera.http://server13.web-mania.com/users/Simond...luestar35mm.wmv The stars are sky blue and are pumped 1cm cylinder shaped. I add them to the film can and then fill the gaps with BP break charge. The can weighs around 32 gramms.
Chris Posted April 25, 2006 Author Posted April 25, 2006 Cheers i will probably buy some take some time to come over to england though. I think i will still go ahead this weekend and make that small one just to gte used to making them.Cannonfuse no longer ships outside the US, yes even paper/plastic products can not be shipped. You can buy them from pyrocreations, they ship outside the US and they have been very helpfull with my enquires. http://pyrocreations.com/miscellaneous Umm, are you sure? Is that stated somewhere on the site? I ordered plastic and paper parts a short while ago, and everything arrived just fine.
Pretty green flame Posted April 25, 2006 Posted April 25, 2006 Cheers i will probably buy some take some time to come over to england though. I think i will still go ahead this weekend and make that small one just to gte used to making them.Cannonfuse no longer ships outside the US, yes even paper/plastic products can not be shipped. You can buy them from pyrocreations, they ship outside the US and they have been very helpfull with my enquires. http://pyrocreations.com/miscellaneous Umm, are you sure? Is that stated somewhere on the site? I ordered plastic and paper parts a short while ago, and everything arrived just fine. I am quite sure. If you look closely you can't even select the country you are in. The only option is the US.
Guest pyrokid00000 Posted April 26, 2006 Posted April 26, 2006 Does anyone know the best type of paper to seperate stars from the breaking charge? Ive been using coffee filters for my 3" shells and i dont think all the stars are igniting properly. I know they are primed good, i just think that the coffee filter is to thick.
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