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Old 10-28-2018, 11:24 AM   #41
johndallman
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Default Re: [AtE] Black Powder vs Smokeless

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Originally Posted by malloyd View Post
Should work OK for black powder, but I'm not so confident a spark will set off smokeless. Electrically detonated explosive charges usually set off a primary explosive primer rather than try to set off the explosive directly.
The first example was a German WWII autocannon cartridge. They mixed normal priming compound with graphite, so that it would conduct electricity somewhat. The cartridge looked normal, because there was a central contact that looked much like a primer, but it was electrically insulated from the body of the case. Putting current through it, and earthing via the cartridge case and gun chamber, gave enough heat to detonate the primer.

The point of this was to get more precise timing of the shot, plus it's techno-wizardry to impress Goering.
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Note that you do need to build the spark gap into the cartridge. Getting a spark out of a battery that will fit in a handgun means a fairly precise gap and a narrow point - expose it to a powder explosion and it is not going to be reusable! This seems likely to be a moderately fiddly bit of machining for each cartridge, and potentially a fragile one, so it's not handicraft production either.
Some imagination would probably allow them to be stamped, but you need a stamping press and consistent materials for it.
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Originally Posted by Luke Bunyip View Post
Would it be better suited to larger calibre weaponry? Mortars? Rifles, anti-material rifle sized calibres? Recoilless rifles? A 1lb/37.5mm Maxim Pom-pom gun?
The bigger it is, the easier this part is. Any of those weapons should work. The Maxim Pom-Pom is fairly easy to build, given decent steel and brass, and a working machine shop.
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Old 10-28-2018, 11:24 AM   #42
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Default Re: [AtE] Black Powder vs Smokeless

My understanding is that smokeless powder needs a blast wave in order to set it off. You can generate a blast electrically, but it takes more work than just a spark. You will need to dump electric energy into the discharge in less time than the spark plasma can expand. Arc blasts are a real danger when working with high voltage equipment. But I really don't know how tough it would be to make an arc blast just using stuff scrounged up from the ruins.

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Old 10-28-2018, 12:55 PM   #43
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Default Re: [AtE] Black Powder vs Smokeless

If manufacturing cases is an issue, you can use caseless rounds like the Volcanic, although the cartridge is rather weak.
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Old 10-28-2018, 01:09 PM   #44
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Default Re: [AtE] Black Powder vs Smokeless

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Originally Posted by copeab View Post
If manufacturing cases is an issue, you can use caseless rounds like the Volcanic, although the cartridge is rather weak.
Caseless just means it's a component of the gun that gets destroyed, rather than a component of the case.
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Old 10-28-2018, 01:20 PM   #45
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Default Re: [AtE] Black Powder vs Smokeless

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Originally Posted by Anthony View Post
Caseless just means it's a component of the gun that gets destroyed, rather than a component of the case.
I have no idea what you are getting at, in response to my post.
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Old 10-28-2018, 01:34 PM   #46
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Default Re: [AtE] Black Powder vs Smokeless

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Originally Posted by lwcamp View Post
My understanding is that smokeless powder needs a blast wave in order to set it off.
That seems very unlikely. Nitrocellulose and nitroglycerine both burn quite well, and the desired behavior for smokeless powder is deflagration, not high-explosive detonation.
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Old 10-28-2018, 01:45 PM   #47
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Default Re: [AtE] Black Powder vs Smokeless

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Originally Posted by Ulzgoroth View Post
That seems very unlikely. Nitrocellulose and nitroglycerine both burn quite well, and the desired behavior for smokeless powder is deflagration, not high-explosive detonation.
Then that should make it easier to ignite with an electric discharge. Although it could still be more difficult that igniting black powder.

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Old 10-28-2018, 05:10 PM   #48
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Default Re: [AtE] Black Powder vs Smokeless

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Originally Posted by copeab View Post
I have no idea what you are getting at, in response to my post.
I assumed that was a response to the electrical ignition discussion.
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Old 10-28-2018, 05:49 PM   #49
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Default Re: [AtE] Black Powder vs Smokeless

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Originally Posted by lwcamp View Post
Then that should make it easier to ignite with an electric discharge. Although it could still be more difficult that igniting black powder.

Luke
https://sciencing.com/properties-nit...e-5078853.html

....says that nitrocellulose has an autoignition temperature of 170 C or 338 F. That may be the right factoid. However....

https://www.quora.com/What-is-the-se...-or-gun-powder

....has the sutoignition temp of black powder beign much higher at 464 C or 867 F.

I still suspect that black powder is somehow easier to ignite as to my knowedge the required safety protocols are greater. It's probably complicated.
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Old 10-28-2018, 05:59 PM   #50
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Default Re: [AtE] Black Powder vs Smokeless

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Originally Posted by Fred Brackin View Post
I still suspect that black powder is somehow easier to ignite as to my knowedge the required safety protocols are greater. It's probably complicated.
Maybe to do with different physical forms? Black powder is a legit powder or even mix of powders. Nitrocellulose is usually in at least somewhat larger chunks.
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