That would be a new item here on Specialized Gear.
The Tank Talk section here is the most likely place to get ideas and such as that is where all the tank, cannon, RPG, Mortar guys hang..
Mortars do not seem too popular just in terms of how often we see them in play. Mortars/cannons tend to break about half the paintballs in the barrel from the acceleration. They spread out like sawed off shotguns. Wide area effect in a mortar. The terminal velocity of a paintball is so low, it has to hit something hard to get a break. Many just bounce.
I am not that familiar with Rap 4 gear. Cerntainly never laid hands on one. but I recall comments about their limited range compared to a Nerf Round out of a RPG or tank cannon that can reach out past 50 yards. If correct, it would be well within infantry range of paintballs and vunerable.
I am your basic air cannon guy. If I was going to build a paint mortar, I would be looking for a way to launch a large number of paintballs out of a paintball barrel and keep them all intact. So far that project has successfully fired 5 balls out of one modified barrel all intact, one right behind the other going 250 fps. Trying to put 4 of those modified barrels in a sabot configuration so I can launch 20 balls at a time. My goal has been an 50+ to 100 yard anti tank round in a RPG configuration but it would also lend iteself to a mortar config as well. Right now, I have difficulty imagining a drop in sabot like a mortar shell would. the barrels would be part of the projectiles. Maybe OK if it only goes 10 feet but I have my doubts. I would have to ponder that a bit. Hasn't occured to me until I read your post.
Using a Nerf round as a mortar round, I would use the over sized ID diameter of schedule 20 thin wall PVC and trim the fins on the Nerf to match the Bulb diameter. USe the pretty standared cannon hardware with a sprinkler valve with electronic solenoid. Just rig a light and photo sensor in the base of the mortar so it would trigger the cannon/mortar when the fins broke the beam. I had a muzzle loader using that thin wall. 30 inch barrel and I would just hold the muzzle up and drop in a Nerf. It would take about 2 seconds for the air behind the nerf to pass to the front of it as it fell. I would hear it slide down and go thunk when it hit the bottom about 2 second later. Just about a perfect time interval for a mortar and to get your hands and head out of the way. So cruise over to Tank Talk section.
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