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  #1  
Old 11-06-2009, 08:39 PM
4redwings 4redwings is offline
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Default BP to smokeless replacement in 29mm AT RMS ejection well

2.6 inch tube, 24 inches long, AT F40W motor. Cannot reduce tube volume due to mission.
Having trouble getting all the laundry out (lots! part of the mission) with the standard BP ejection charge that comes with the reload kit. Can't get my hands on BP to add a little oomph to the charge.

Has anyone replaced the BP with Red Dot or Pyrodex P in the AT 29mm/40-120 reload? Will the delay grain light it?

Thanks!
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  #2  
Old 11-06-2009, 09:37 PM
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GregGleason GregGleason is offline
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Have you tried a piston? Typically they do not require as much BP because of the how much of the gas is turned into mechanical movement.

Greg
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  #3  
Old 11-07-2009, 08:31 AM
4redwings 4redwings is offline
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I've never tried a piston. Do you just sand down a coupler with a bulkhead in the top? I don't suppose you'd want it too tight.
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Old 11-07-2009, 10:21 AM
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GregGleason GregGleason is offline
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See this thread starting at post 8.

Attached is a .pdf that you can print out and glue to cardboard that fit the 2.6" tube (rubber cement is better, 3M Super 77 spray adhesive is best) and just cut out the pattern using scissors.

The rectangles on the side are 1" inch increments used to dial in your printing scale.

Greg
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File Type: pdf PistonGuides.pdf (20.4 KB, 73 views)
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  #5  
Old 11-08-2009, 10:50 AM
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ghrocketman ghrocketman is offline
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I have heard of people using Pyrodex or Triple Seven as a replacement for black powder in ejection charges; The key is taping over it VERY securely to allow more pressure to build up.
DO NOT try Red-Dot; that is smokeless pistol powder and it will NOT work unless you encapsulate it in a manner to allow a large amount of pressure to build. Why don't you just mix in some Pyrodex with the black powder supplied in the reload ? It won't hurt anything; some shooters do this in their muzzleloaders. I guess I'm lucky when it comes to black powder; there is a gunshop within 5 miles of my home that I can purchase black powder all day, everyday in 1 and 5 lb cans as well as 10lb kegs. Have not bought any in at least 5 years though; I think most they sell is used in saluting cannons; most that shoot muzzleloaders switched to Prodex or 777 long ago.
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  #6  
Old 11-08-2009, 06:03 PM
4redwings 4redwings is offline
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I wondered if anyone had ever just added a little bit of Pyrodex to their ejection charge. That seems like an easy solution. The only place around here that I know of that stocks black powder is over an hour away. I can get Pyrodex almost anywhere.
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