grind the gear or grind the piston?

Vents

Right, here's the story.

I stripped the bevel gear in my Dboys M4. So I'm taking the opportunity to replace a few other bit while the case is open.

piston (to a light nylon full steal tooth)
piston head (silent head)
cylinder head (silent head)
Gears (Speed set)

Now, here's the problem. The piston seems to be a little longer than the original piston (2/3 mm). the teeth are the same length as the original and the sector gear has the same number and spaced teeth but when I dry fit it all together the gear teeth do not release the piston before the piston reaches the back of the box (spring guide)

So, Do I;

a) grind the last piston tooth down so the piston releases
b grind the last gear tooth down so the piston releases

I think both would do the trick, but which one is preferable?

Dread-Lock

I'd take the tooth off the piston.

Private Snafu

Definitly the piston (cheaper to replace if something goes catastrophically wrong :P)

Vents

Thanks for the replies.

thinking about it a little more, The piston would be the way to go as the gear would be weighted to spin of it's axes.

Masada

It sounds a little odd to be having such a problem, Is there a bearing spring guide in there aswell? anything preventing the piston from traveling all the way back?

Vents

Masada wrote: »

It sounds a little odd to be having such a problem, Is there a bearing spring guide in there aswell? anything preventing the piston from traveling all the way back?

not at the moment. (was hoping to get one in) Just a bog standard guide.

the pistons position on the back stroke is flush with the correctly seated spring guide. at the moment the two sets of teeth are still connecting.