Hey DF
Since you bought a recoil unit I assume that the JP was originally a BB version yes?
The BB barrel will not go into the recoil unit without serious modification. It is a big job and Gra can certainly help with how you are going to have to deal with the plastic parts of the barrel.
Coincidently I've been working on recoils this week and you are going to hate me but striping down and using the old bb motor caseings as the recoil unit is just as easy as using the recoil unit itself.
bb_case_servo.jpg
One of the easy parts is attaching the aluminium tube for the bb onto the recoiling breech. A 32mm length of shrink tube is perfect. The shrink tube not only allows an easy quick join but it is also cheap
and provides a bit of flex.
bb_case_barreljoin.jpg
Just a thought - after all if you have an old BB unit lying around you have nothing to loose giving it a go.
Cheers
Kevin G
