This is something I have wanted to build for a loooong time... I think the goal is within reach.
Before I start making parts I want to run the idea by the group for input.
Probably easiest to start with an existing PCP and slap a bigger barrel on it. That got me wondering which one would be a good choice? I don't want it to be weak nor should it be lethal... so I started doing some calculations.
My best guess at a target muzzle velocity is 100mph. Being able to adjust this waaay down will be important, but more power on tap probably isn't a bad thing. More on that later. 100mph is about 150fps and with a tennis ball weighing about 58 grams that puts it in the 45fpe range. Seems very doable with a typical 25, 30 or 35cal pcp.
Next question is controlling the power level. Regulated air is always nice but I don't know if that will make any sense in this context... I'll leave that for later. Assuming an unregulated air supply, hammer spring is probably the next best way to control power. I'll definitely need something with a spring adjuster.
For the barrel and loading mechanism I'm not being too picky at this point... maybe start with muzzle loading and if it works well I can design a pump action single shot mechanism. Another though was to have a hop-up in the barrel to keep the ball from rolling out. Also, hoping for a short barrel... I don't want something so large that it is cumbersome.
My first though was to use my 357 HP SS Max and slap the most basic tennis ball sized barrel I can make... seems to be the path of least resistance. Hammer spring adjustment sucks but it can be done externally.
This definitely isn't a new idea and there is some prior art to learn from. I remember seeing a propane powered pump action some 10 years ago. If you know any previous designs that can provide insight please share them here.
All of that said... am I barking up the wrong tree here? I'm concerned that high pressure air may be too much for a tennis ball. Is a short burst of high pressure similarly effective to a long burst of low pressure?
Before I start making parts I want to run the idea by the group for input.
Probably easiest to start with an existing PCP and slap a bigger barrel on it. That got me wondering which one would be a good choice? I don't want it to be weak nor should it be lethal... so I started doing some calculations.
My best guess at a target muzzle velocity is 100mph. Being able to adjust this waaay down will be important, but more power on tap probably isn't a bad thing. More on that later. 100mph is about 150fps and with a tennis ball weighing about 58 grams that puts it in the 45fpe range. Seems very doable with a typical 25, 30 or 35cal pcp.
Next question is controlling the power level. Regulated air is always nice but I don't know if that will make any sense in this context... I'll leave that for later. Assuming an unregulated air supply, hammer spring is probably the next best way to control power. I'll definitely need something with a spring adjuster.
For the barrel and loading mechanism I'm not being too picky at this point... maybe start with muzzle loading and if it works well I can design a pump action single shot mechanism. Another though was to have a hop-up in the barrel to keep the ball from rolling out. Also, hoping for a short barrel... I don't want something so large that it is cumbersome.
My first though was to use my 357 HP SS Max and slap the most basic tennis ball sized barrel I can make... seems to be the path of least resistance. Hammer spring adjustment sucks but it can be done externally.
This definitely isn't a new idea and there is some prior art to learn from. I remember seeing a propane powered pump action some 10 years ago. If you know any previous designs that can provide insight please share them here.
All of that said... am I barking up the wrong tree here? I'm concerned that high pressure air may be too much for a tennis ball. Is a short burst of high pressure similarly effective to a long burst of low pressure?
