Tip to extend the life of black smith tubes

[jonk]

I have found consistently that before my flash holes burn out, or the tube otherwise becomes unusable, the mouth starts to roll over toward the outside, creating a ring that makes chambering hard. NOT a situation you want to face on a timed event!

For some time I considered what to do with these. It was a burr. A razor knife would cut into the hard plastic, but not easily, and not evenly. If you have a lathe, that would work. But I don't.

Voila.

Bench grinder. Spin up the grinder, spin the case in your fingers at a 45 degree angle, mouth to stone... and you have a perfectly beveled case, ready to rock and roll again.

I admit, this is being cheap. I'd probably not use these cases as a front line choice. But they seem to shoot just fine. Just thought I would share.

[Jim Brady Knap's Battery]

Just a caution. In all my years of rotary wing aviation maintenance one thing that would land you in deep stuff was to place anything against a grinder stone that did not produce sparks. Soft metals, phenolic, wood, anything that was non ferrous was forbidden. The concept is that soft material can/will imbed in the surface of the grinding wheel causing it to go out of balance and have a sudden and rapid disassembly with fragments tossed about at very high speed causing injury to the user. Maybe not the offending user but perhaps the next unsuspecting person. I'm not sure the plastic of the Smith tubes would be exempt from this.

[B Buck]

Use a fairly coarse grinding wheel and if you start to notice it loading up with plastic use a wheel dresser to clean it up. Also don't force the plastic into the wheel. Take small amounts off at a time. If the plastic gets hot it will load up quicker. Also consider something like a belt sander with a coarse belt, again remove a little at a time to avoid heat. There are compounds available that you can use to keep the belt clean too. One thing you might want to consider with grinding plastics is to wear one of those cheap throw away paper respirators.