First of all, thanks again to Kap!
Here are some shots of the little mortar in action.
Projectile is a standard paintball, no patch.
The powder charge in the first photo is a chamber level full of FFFg, roughly three grains. In the other photos, the mortar was loaded using the .3cc dipper from my Lee kit, approximately 4 grains of FFFg. This charge slightly overfills the chamber, but not by much. This was done mainly for convenience, since I don't yet have a measure that throws the exact volume of the chamber.
I've found that the .3cc charge gives a little more smoke/fire but about the same downrange effect as the level full chamber, while any more powder gives very erratic results. I believe that this is becuase the soft paintball will give enough to fully seat over a slight hump in the powder charge. I need to make the correct measure.
I also tried FFFFg powder and was not impressed. The FFFFg gave very poor report and only threw the paintball about half as far as an equal amount of FFFg.
I was using the premium 1/16" fuse, which is a little fatter than the cheap stuff, and it's a VERY tight fit in the vent. The vent must be cleaned thoroughly after each shot. Not a big issue, and I definitely do
NOT want to drill the vent larger.
The paintballs will only break if they hit a certain way on hard pavement. The best shot I could confirm point-of-impact was 45 paces with the .3cc charge. Most of the shots were just for fun and lobbed onto the roof of the empty duplex next door.
It's not easy to see, but there is a small block of wood sitting behind the barrel. This was to keep the sparks from the fuse off the base. I plan to mount a brass plate to the base in the future.
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