Author Topic: Airspace in powder charge  (Read 525 times)

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Offline rusty barrels

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Airspace in powder charge
« on: February 13, 2007, 06:29:26 AM »
Last night I tried to make a couple of charges to see how much trouble I was gonna have. I have a 2 1/4 bore hern 2/3 1841 barrel and I can't seem to make a charge without some airspace between the plastic bag and foil, at least for a 1 ounce charge, I didn't want to pound it down too hard. I also noticed if I did it would be very thin like a cookie. I wanted to start with 1 ounce  for projectiles but now I wonder if I should use plastic wrap for better forming and a starting load of 2 ounces.

Offline Double D

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Re: Airspace in powder charge
« Reply #1 on: February 13, 2007, 07:47:13 AM »
When I put my plastic bag of powder in the fouil tube, I twist the top of the foil tube shut until twists up against the bag of powder inside.  I the cut the long twisted tail off.

Offline Rickk

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Re: Airspace in powder charge
« Reply #2 on: February 13, 2007, 12:29:02 PM »
Rusty Barrels, I feel your pain.

My 2.25 inch Hern mortar likes 170 grain charges for 100 yard shooting. That's about 1/3-ish of an ounce

I just fold the top of the foil cup over as tight as I can. There is no airspace on the top/bottom, but there probably is some on the sides in places. I do put in a couple baking soda soaked 1/8 inch cardboard wads on the top to make the powder column longer. It probably makes the foil bag compress better as well. If you do that, clearly mark the cardboard end with spraypaint.

I tape the charge to the ball with masking tape and let gravity help load it... it is a mortar and the 45 degree angle helps. I then tap it firmly a few times with a U-shaped ramrod. I'm sure there is some airspace on the sides. The top gets compressed pretty good.

Try a u-shaped ramrod to eliminate any issues.

Offline guardsgunner

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Re: Airspace in powder charge
« Reply #3 on: February 13, 2007, 12:48:07 PM »
Rick,
    Mortars are usualy loaded with loose powder and should never require a ramrod, U shape or otherwise. There should be enough windage to allow the ball to roll out if there is a problem.
There is always some air space in a mortar.

Offline Rickk

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Re: Airspace in powder charge
« Reply #4 on: February 13, 2007, 12:56:58 PM »
This mortar does not have a sub-chamber, so there is no airspace by design.  The ball rests on the charge.

Loading a loose charge without a subchamber would cause some issues with placement.

And then there is Massachusetts (the state I live in) which actually mandates plastic bag inside of foil.

I have plenty of windage. The ramrod is more of a safety check than rammer. The 2# ball falling on the powder bag should pretty much flatten things out inderneath it. Yes, I have a bore gauge and all, but nothing wrong with double checking.