Cocker help please.

[Karizma]

I've just fitted a Nexus ram with QEVs to a nearly stock Cocker. With the original ram I never had a problem, but, since I fitted the Nexus it's done nothing but chop balls. Have I missed something simple, or does it need an adjustable LPR to lower the cocking pressure? Any suggestions please.

[Parksy]

I got this when I added a Nexus ram and qevs to my Evo cocker (non electro). It caused massive ammounts of blowback which caused chopping big stylee :(

Heres how to check if you have the same problem...

With no hopper on the marker drop 2-3 balls into the feed neck.

Fire the marker as you would do normally. Look at what happens to the ball stack. Does the top ball jump up significantly enough to see (slight blowback) or does it even jump out of the feed neck altogether (bad blowback). If you do have blowback it causes half feeds etc into the breech for obvious resons :(


P.S. Had to remove my Qevs to solve the problem on mine :(

[Tom]

Ok,

I would guess that the blowback caused by adding qevs is caused by the bolt opening much sooner after the shot than without the qevs, to the point where the pressure in the barrel hasn't dissipated - thus causing blowback as L1F3 described (Why you would put qevs on a non electro cocker is beyond me though :P). If you have an electro cocker that is chopping after you upgrade the ram / add qevs, it's likely that you just need to turn the dwell up a bit to stop the breech opening too soon.

Or it could be something totally random, but try just upping the dwell a bit first. You should still get an improved overall cycle rate since the bolt will probably move much faster throughout its whole range of movement.

[Karizma]

Cheers guys, looks like dumping the QEVs is the way to go until I E-blade it. Soon as I get chance to shoot the garden fence again, I'll let you know what happens. :)

[Tom]

Just re-read your original post - I think you will need to lower your lpr pressure - which means you do need an adjustable lpr. They aren't too expensive at least!

[Karizma]

Cheers for that Tom, funny you should mention getting an LPR, one arrived on the doorstep this very morning. I'll let you know what happens. :D