Guys, I have just built an airsoft barrel recoil into my HL M26 using a clark board and a servo with an attached pull rod to the outer barrel sleeve. It works great and I will post a video soon.

The problem with the King Tiger,panther,Pz3/4.challenger,leopard and others is the barrel is used as the main airsoft rifling with no outer sleeve to pull back. With the 6mm BB and at this scale, I dont think these models lend themselves well to having a recoiling barrel other wise you would see more on the market. You would need to recoil the whole airsoft installation in the turret which would be really problematic and space may prohibit this. I'm really keen to do as many models with a recoiling airsoft barrel as I can but I think this factor will limit the choice.

Good luck

Cheers

CaptB