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Karl

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I've noticed a few times now that when a motor has been used ( all from the same pack ) there seems to be a unusual purple'ish residue around the nozzle. And more times than not when I see this , 40%% of the ejection clay-nozzle is still in place even though the ejection fired ?
Thanks
Karl
 

Steward

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Awhile back I attempted to fly my PHEONIX on a D12-5.
It only got about 50 ft off the ground...and of course the ejection charge went off as it was laying on the ground.
Further investigation of the expired motor showed a radical burn pattern in that rear cap... I guess that it burned through and did not (explode)... I don't believe I have ever seen anything like it...I don't think that is normal...
Now I'm concerned that it could be the whole lot (batch).
 

Wingarcher

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I own and shoot a couple black-powder long guns. After each shot there is a lot of "crud" on the inside of the barrel. Frequently there are little solidified beads of purple or almost redish "stuff". Black powder is black powder, whether it's in a motor or loose in a rifle.... I suppose the motor nozzle is a good place for the "crud" to build up thus you get lovely colored blobs. :)

The ejection charge is only as strong as it needs to be (and sometimes not!) so it only creates enough pressure to blow out through the path of least resistance through the cap. As soon as the cap breaks through in one place the pressure drops behind it. With the reduced pressure there is no incentive for more of the cap to break away. If you got a "hot" charge, I suspect the cap would be gone more completely. I think you could probably get the whole motor casing to vanish too... :p
 

jerryb

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same here...I have been shooting Black Powder for almost 12years.. red, orange, and purple "beads" are common occurances in black powder residue... they are from impurities in the components in the BP... the orange and reddish stuff is from iron and copper traces in the mix... not sure what the purple stuff is from

nothing to worry about though... crud is crud...

later
Jerryb



Originally posted by wingarcher
I own and shoot a couple black-powder long guns. After each shot there is a lot of "crud" on the inside of the barrel. Frequently there are little solidified beads of purple or almost redish "stuff". Black powder is black powder, whether it's in a motor or loose in a rifle.... I suppose the motor nozzle is a good place for the "crud" to build up thus you get lovely colored blobs. :)

The ejection charge is only as strong as it needs to be (and sometimes not!) so it only creates enough pressure to blow out through the path of least resistance through the cap. As soon as the cap breaks through in one place the pressure drops behind it. With the reduced pressure there is no incentive for more of the cap to break away. If you got a "hot" charge, I suspect the cap would be gone more completely. I think you could probably get the whole motor casing to vanish too... :p
 
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