Containing Smokeless Powders

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Most people wouldn't store flash. It is way too sensitive. Most make what they need the instant they need it. You can store flash but you need a Type 2 magazine, which has to be bullet resistant, basically same kind of magazines used to store HE.

Even commercial flash powder that you can buy comes in 2 bottles, you mix what you need right when you need it.

The issue with bp is that since it's an explosive, if you use it for anything other than sporting use, then the ATF could require you to have a permit for it. Furthermore since bp is an explosive, the store who carries it would require extensive licensing and storage, so most places aren't going to have it especially when black powder substitutes do not have nearly the same storage requirement that bp have. It is not hard to make them yourself but if you transport it without a license, it's illegal. I should probably check with pyros on how they get around that (taking their own shells to PGI conventions for example). However I am not sure if RSO's will allow homemade bp as ejection charge on their range.

You could make the bp you need right when you need it (at the launch site, though I suspect the RSO will not allow it), however since bp requires a lot of preparation and granulation (though in practice you just need a few grams per flight anyways... you could make it with a mortar and pestle if you are patient). Also making bp takes skill and luck... then you have to wait hours for the bp to dry once you granulate it.

I don't know how it works legally with reload kits including black powders in its ejection charge however... Maybe it has to do with EX certification that those motors have to have??
 
Well that sucks, I wonder how does the addition affect how bp subs are sold/used? Does that mean also that smokeless powder used for reloading have to be kept in a magazine by the dealer?

By that logic it could mean that rocketry is effectively impossible because now you'll need an explosive permit to use any ejection charges.

Maybe that's the ATF's way of getting back at the rocketry group for getting APCP removed from the list?
 
While you are basically right, your statement needs some tuning.

BP does not explode. It deflagrates. That is a technical term that the pressure wave stays below the speed of sound. Furthermore, not all BP deflagrates at the same rate. BP ffff burns more quickly than the BP ff, because of the differing grain geometry and how they interact with each other in close proximity.

C4, RDX, and PETN explode, in that they generate a shock wave. There is a big difference in how a 1 gram of BP behaves than 1 gram of those other three. One will deploy your recovery gear and the others will turn your rocket into confetti.

Smokeless powders have varying rates of deflagration based upon the intended application. Generally, pistol powders burn faster than rifle powders.

Greg

I will agree with the tuning. The rest of the post is good information. You can add shotgun powders to the pistol powders for high burn rate as well. Shotgun powder typically have faster burn rates than pistol powders (one burn rate chart I've seen has N310, Titewad, Nitro100 ahead of even Bullseye one of the fastest pistol powders).

Hmmm..confetti the new tracking powder?

IMO all HEs are excessive for our hobby, especially if the individual is not a specialist in that field, confetti would be cool on somebody else's rockets but not mine.:facepalm:
 
They have been classified as explosives ever since the SEA went into effect a decade ago. There are exemptions and exclusions all through the regs that allow private citizens access, even to BP (antique firearms).

I really doubt the ATFE cares enough about rocketry one way or another to bother. They have far bigger problems.

KO
 
true, but that could change. For example they were having enforcement actions at PGI conventions so I wouldn't be surprised if some guy got in trouble for using bp in ejection charges.
 
Well you could always use flash powder... it burns very fast with minimal confinement and sometimes self confine to produce a report... They can also be quickly mixed from 2 chemicals so can be quickly made on site without preparation (like black powder), however a few problems:

Flash is sensitive, and static electricity can set it off. A few grams is enough to blow your eardrums if it went off in front of you, and if you were unlucky you'd lose fingers. Also they are fairly brisant, while not high explosives per se, since they don't produce supersonic shockwave, they still burn fast enough to seem like high explosives, mostly because they can self confine in quantities above .5 grams (depending on the formulation). Also since the reaction of flash powder produces very little gas, they aren't well suited for applications requiring a lot of expansion... Chances are it will turn rockets into confetti.

It makes no sense to detonate 1 gram of C4, C4 requires a blasting cap to set it off (otherwise it just burns very slowly... impact, bullet hit, or fire will not cause it to explode). The blasting cap required will contain more than 1 gram of high explosives for sure. PETN might detonate in that quantity however since it's a bit more sensitive.

One HE that may work well is sodium azide, however in addition to being very sensitive it is also very toxic. Airbags use them but they are mixed with other things to ensure that no sodium azide or other hazardous reaction products (such as sodium) remains once the airbag deploys.

I'm still wondering about confining smokeless ejection charge by pasting it with gum tape or glue soaked kraft paper... it would create a really hard outer shell to confine the powder, just like blank ammunition.
I have no idea who you are, what your background is, and whether or not you have an explosives permit but you have given some very bad information. You propose to put pyrotechnic flash powder in quantities approximately equivalent to an M-80 in a hobby rocket, however in the US, civilians are not allowed to purchase, store, use or transport any pyrotechnic device containing more than 50 milligrams of flash unless they have an explosives license. Furthermore several grams of flash going off inside a rocket would shred the rocket before deploying the parachute, so the rocket could justifiably be labeled a weapon, and you would be eligible for a long expense-paid vacation at Club Fed wearing a fluorescent orange suit if you built your recovery system this way. Don't even consider it.

C4 is a plastic high explosive, and requires an explosives permit in any quantity. While it, or an equivalent high plastic explosive, has been used to separate the NC from a booster in at least one large Class 3 amateur rocket, it is useless in deploying a parachute as the detonation of any high explosive would totally shred a parachute before it began to move.......

Sodium azide is not a high explosive, and is not very sensitive. (I know because I worked with it daily for a year to measure the thermal decomposition kinetics for DOE.) It thermally decomposes rapidly into nitrogen gas at high temperature, and when mixed with BP or a BP substitute, forms a nitrogen gas generating pyrotechnic mixture used to deploy airbags........

Smokeless powder replaced BP in firearms for 2 reasons: the first reason was that it doesn't make smoke, and more importantly it burns much slower than BP which allows the acceleration of heavier projectiles to higher velocities at higher pressures without blowing up the gun barrel. BP burns so fast at pressure that if the projectile is too heavy, the BP pressure in the breech will increase faster than the trapped breech volume increases as the bullet accelerate down the barrel and the barrel will explosively disassemble. Smokeless powder burns 10 to 100 times slower than BP and can produce a nearly square pressure pulse by changing the grain geometry to optimize the pressure time history in the breech for a specific sectional density projectile. Single base smokeless powder is nitrocellulose, and the primary difference between all the single base powders is the nitrocellulose grain geometry.

BP burns so fast near sea level that it will pressurize you parachute compartment in a millisecond or so, but the burn rate of smokeless powder is so much slower that most of the powder grains will not ignite and those that do generate sufficient cold gas to push unburnt propellant grains out of the way without igniting them. The only way smokeless propellant works as an ejection charge is to confine it at several hundred psi in a rigid walled chamber so that all the grain ignite before the grains start to move away from each other.

Finally, the use of BP substitutes and smokeless powder were only considered by rocketry folks because they, unlike BP, were not specifically regulated by BATFE. That changed in 2013 when the BATFE included black powder substitutes and smokeless powders to the explosives list. BP and its substitutes and smokeless powders by law are not regulated by BATFE if you purchase them for hunting and/or reloading up to a 50 pound quantity. In most states, if you are a hunter or reloader, you can legally purchase any of these propellants without a federal explosive permit, and if you're not a hunter or shooter, in some states you will need to show a BATFE permit/license to purchase them legally.

That's the law, and 10,000 rocketeers do not have the clout to change them. It the National Association of Rocketry had simply named their organization the National Rocketry Association back in the 50s when the hobby started, we might not have this problem today........:wink:

Bob Krech, TRF Moderator
 
Sorry, I think you misread me.

I'm not advocating the use of flash powder, C4, or Sodium Azide in any rocket, I was explaining why they would make a poor choice for recovery. I'm sorry for not making myself clear. Please if anyone thinks I'm talking about dangerous things pm me because I'm not too good at communicating, and often I'd talk about something and people would interpret it as me advocating something.

In the interest of not sending the wrong message, I've removed the portion of that post that talks about flash powder.

I just thought how firework shells are heavily confined (with several layers of hard paper) and wondered if this would be sufficient to confine smokeless enough to push nosecones out. I mean blank ammo uses smokeless and they are only confined by a crimp at the end of the cartridge (rather than a bullet). They have been used to drive nails... or shoot grenades in wartime (those M1 Garands that have special grenade adapter that allows you to launch grenades by using a blank ammo) so it's just a matter of confinement.

I'm just dismayed to hear they added bp subs/smokeless to the explosive list because those are more available and less regulated. Perhaps this is the way the ATF is getting back at getting APCP removed. I tried googling this but I'm finding very little information on this. Nearly all the sources still say that smokeless powder, pyrodex, etc. are unregulated but the 2013 ruling seems to say different. One reason few dealers carry bp is because they have a much higher standard for storage and licensing, so most sporting stores don't bother carrying them. Could the 2013 ruling mean that smokeless/bp subs have to be treated like bp, meaning licenses to sell, extensive storage requirements, etc.?
 
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I'm just dismayed to hear they added bp subs/smokeless to the explosive list because those are more available and less regulated. Perhaps this is the way the ATF is getting back at getting APCP removed. I tried googling this but I'm finding very little information on this. Nearly all the sources still say that smokeless powder, pyrodex, etc. are unregulated but the 2013 ruling seems to say different. One reason few dealers carry bp is because they have a much higher standard for storage and licensing, so most sporting stores don't bother carrying them. Could the 2013 ruling mean that smokeless/bp subs have to be treated like bp, meaning licenses to sell, extensive storage requirements, etc.?

I know that in the area I live in no one in the cities of Pasco/Richland/Kennewick carry BP (that includes all the local gun stores, and the local Sportsmans Warehouse) but you can still get Pyrodex in town. The nearest place to buy BP is 30 miles away. The reason is that the city ordinances don't allow them to have more than a few pounds on hand at anytime no matter what magazine they have. Its kind of a classic case of if the ATF set X-standard then making it more restrictive is better for everybody (the ATF standards are plenty restrictive enough without local and state governments putting their paws in the same pile.

Edit: That is very true that state and local laws are more restrictive than the federal ones since they cannot be any other way AFAIK, at least on most Federal Regulated things (unless its Marijauna of course).
 
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.....city ordinances don't allow them to have more than a few pounds on hand at anytime no matter what magazine they have. Its kind of a classic case of if the ATF set X-standard then making it more restrictive is better for everybody (the ATF standards are plenty restrictive enough without local and state governments putting their paws in the same pile.

Actually, this is pretty common practice across the country. For example, if you want to construct a magazine on your property, you start with the local authorities. If you don't have their approval, including zoning and fire safety, the ATF will not even inspect your mag.

Local ordinances are usually the most restrictive, both for storing and using explosives. State laws are next, and the ATFE regulations the least restrictive of the bunch. It makes sense if you think about it. The ATFE says if you meet their requirements for setbacks, you can build a magazine and store explosives. Heck, they'll even let you have a small one in an attached structure. However your neighbors may have some opinion on that, which is where the more local ordinances come in. Towns regulate the use and storage of explosives for reasons of fire safety, theft deterrence, liability concerns, and local sentiment.

That last is the toughest to overcome. An example would be if an individual wanted to build a magazine to store up to 1000 lbs of dynamite one-quarter mile from an elementary school. This would be perfectly acceptable from the ATF's point of view, and would be a safe distancing. However "1000 pounds of dynamite" and "elementary school" are probably mutually exclusive terms in the minds of the public.

This is not to say some locales don't go overboard on regulating such things. Many times such over-regulation stems from past experience, and is perpetuated by bureaucratic inertia.

Kevin O

PS> Sorry to sidetrack this thread, but I've become quite familiar with the regs and the process. I have a magazine, make and store explosives, and serve as an elected official in local government. I tend to see these issues from a fairly broad perspective.

PPS> I've tried smokeless powder and BP substitutes for ejection. They work well enough if you contain them in a piece of rubber tubing, held closed with zip-ties. BP is still far easier to use.
 
Bottom line ....
Is there anything that can legally be used to make ejection charges without a LEUP??
 
Yup, if you have a valid reason to own Black Powder, a revolver or rifle made to use BP, then there should not be a problem going into a sporting goods store and purchasing a 1lb can of Black Powder (Fffg), Pyrodex, or Triple7.
I believe that the standard dude on the street can have up to either 10 or 50lb* of BP without need of any permits, etc.

*I would have to look up the exact amount.
 
Thing is, some states/cities/counties do not allow muzzleloaders (sometimes for certain "prohibited persons", others for all such as NYC). As far as Federal is concerned even if you are an illegal alien AND a convicted felon, you can still own blackpowder firearm AND blackpowder (which the SEA would not allow you to own otherwise). That is actually what the ATF said by the way (www.atf.gov/files/firearms/industry/0501-firearms-top-10-qas.pdf) There are even "modern" cartridge firearms using smokeless powder that also falls under "antique" if made before 1899, such as some Mosin Nagants or Turkish Mausers... It's funny how that works. I suspect if say firearms get banned or severely restricted sometime in the future the antique firearm thing could be used to say that they still kept the second amendment right... (since it was written at a time when the only guns out there were black powder).
 
In Washington state iirc (from my gun store working days) a convicted felon may not purchase or possess any firearm modern or primitive/antique. That law also applies to non-US citizens and illegal non-citizens. And Washington just passed a law requiring paperwork for all gun transactions, to be completed by a FFL dealer, now in Washington its illegal to even loan a firearm to another person or give one to a family member as gift without doing a FFL transfer (Its amazing that one county in WA state by itself determines the rules for everyone else, King county has more people in it than almost all the counties combined).

BP is still best for rocketry though, unless you want to try the CO2 systems that are out now.
 
What, so even a legal permanent resident can't own guns in WA? What about people coming over to the US as a tourist for hunting trips, or going to shooting ranges?

https://www.nraila.org/gun-laws/state-laws/washington.aspx
According to this I don't see any indication that WA's law on antique firearms are different than Federal's definition.

Bp is best but I feel even if you do own a bp gun, but you are using the bp for other purpose, that may still be technically illegal. Like if you own a modern in line muzzleloader and you have 4F that may seem weird if some authorities decide to check on you, since in lines don't use 4F. I'm wondering if some aerodynamic system could be used, where a small amount of pyrotechnic (basically just the pyrogen of the e match used to set off the ejection charge) would release a flap or catch where the aerodynamic forces would cause a drogue chute to pop out, and the chute would drag the main chute out.

Actually, I think a better legal solution may just be for the club that the person fly in to obtain a ATF license, and buy commercial black powder to be used at club events. I don't see how one would want to fly HPR outside of club events (since you needed FAA clearance anyways) and one can of bp is enough for hundreds of flights. That way no one else would have to worry about getting ATF license.
 
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I also live in WA... the new laws are not quite as stated... the new laws do not apply to transfers between immediate family members, nor does it apply to "The sale or transfer of an antique firearm". Although I did vote against it, it isn't as bad as people are making it out to be. I've read the law and it exempts a lot.
 
So back to the original thread before it turned into a discussion about legalities, has anyone tried to confine the smokeless powder by pasting the container and then spiking it with threads?
 
For the ejection container, if you don't have a lathe don't fret. It's not exactly precision machining so you could just take a brass rod, and drill a hole down the center with a drill press, and a smaller hole for the igniter wire to go through.

Has anyone tried the spent ammo brass yet? I imagine it wouldn't work by itself without some beefing up (the brass would probably blow apart) I guess if anyone wanted to try nail gun cartridges you would need to have a mechanical device to release a hammer to hit a firing pin... too complicated.
 
A mixed bag of unknown flake and ball powder? That's got the potential to go real bad, real fast. Most flake powders are pistol and shotgun variety, and those are the fastest burning on the charts. Ball powder could be pretty much anything. You really don't want to continue on this path. The wrong stuff, in the wrong container, has the potential for a very nasty pressure spike. Particularly if you have no idea what powder it is. To put it in perspective, a 5 grain charge of the right powder makes a very strong load for a .45ACP.
 
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For the ejection container, if you don't have a lathe don't fret. It's not exactly precision machining so you could just take a brass rod, and drill a hole down the center with a drill press, and a smaller hole for the igniter wire to go through.

Has anyone tried the spent ammo brass yet? I imagine it wouldn't work by itself without some beefing up (the brass would probably blow apart) I guess if anyone wanted to try nail gun cartridges you would need to have a mechanical device to release a hammer to hit a firing pin... too complicated.

Shotgun hulls work great. 410 or 12 gauge, and you can cut the plastic down to suit the height you want. I tried a few 9mm cases, but they were too small, and I wasn't going to waste any 45LC.

has anyone tried to confine the smokeless powder by pasting the container and then spiking it with threads
If you are talking about smokeless rifle/pistol/shotgun powder (nitrocellulose or equivalent) and not Black Powder or its subs (Pyrodex, 777) then I would reiterate that it is really not the correct tool for the job.
(oh... btw... Pyrodex and 777 are by no means 'smokeless')
 
1/2 inch cpvc cap drilled and screwed to the bulkhead. ($0.59) >6" of 1/2 inch cpvc pipe with one end glued shut. (~$1 per foot.) Shoe Goo works cause it has some resiliance. (I don't know what depth of glue "fails".) Aim for 1/2 inch. When it dries, sick that end into the cap. Run your ignitor up the side of the pipe, and all the way down into the bottom of the pipe. Dribble your Pyrodex down around it. Now stuff the pipe with dog barf, but not hard. Just enough stuffing to contain the powder in the far end of the pipe (important for the DD drogue charge which is upside down) and to give the expanding powder gasses something to push against so they expand while still contained in the pipe and reliably burn all the powder. Don't compress it. Fill it. Place masking tape over the top, and around the ignitor wires, and the pipe to cap joint.
The length of the pipe can be sized to do 2 things. The Pyrodex is contained long enough to burn instead of getting scattered. Your chute is "next" to the pipe rather than down-range of the cannon. If set up well, a nice stiff bulkhead or engine case gets shot by the "cannon ball" of dog barf, there is no "bang" just a "poof", burning grains of powder are not injected into your recovery fabrics, and everything that falls to the ground is biodegradable.
 
That may be a requirement of your state. I have purchased BP at a local gun shop and was never asked for ID, nor did I need to sign anything.
 
I also live in WA... the new laws are not quite as stated... the new laws do not apply to transfers between immediate family members, nor does it apply to "The sale or transfer of an antique firearm". Although I did vote against it, it isn't as bad as people are making it out to be. I've read the law and it exempts a lot.

This is not the forum for this debate, however you are incorrect. I cannot loan my gun to my daughter. I can GIVE it to her as a gift, but it has to be a legitimate gift and not a temporary loan.
 
In the UK, just about everyone uses pyrodex for DD, mainly because it doesn't require an explosives licence, though some rocket motors do. When I got my explosives licence I didn't bother to get bp added because pyrodex does the job just fine as long as it's Pyrodex P (fffg). I also tried some triple 7 which the guy from the gun shop gave me to try out, this works well too.
 
Hi, I'm the OP.

I found a can of 4f BP. Everything is fine. Nothing to see here.......:)
 
A little firearms history leads me to an idea.
Cartridge firearms were originally loaded with black powder from their inception until around the turn of the century.
You can tell their Black Powder origins for the most part by their names. Cartridges such as 44-40, 45-70, 32-20, 45-110 etc. all began as black powder loaded metallic cartridges. So cowboys like me, for authenticity, actually still load these calibers with black powder. If you had one cartridge of the larger rifle calibers It would contain plenty of black powder for many ejection charges. Think Quigly Down Under.
It would be a legitimate antique firearms use, and convenient if the bullet was a bit loose.
 
leaving out the issue of dismantling rifle ammo, of concern is the type/size of the powder grains. for rocketry, the preferred size is 4f(priming powder), rifle powder burns slower.
Rex
 
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