G&G Scar L/Mad bull Hopup issue

[hickupper]

Hi,

I am trying to upgrade my hopup on my Scar with a new Mad bull hopup, but it does not fit into the barrel very well. I can shave this down to fit, but only if I can get my other issues to work.

The stock HU unit has a cup cut into the nozzle side of it and the mad bull is a solid cylinder, so I cannot drop my mechbox back in when I have it all installed. I tried to compress the nozzle into the mech, but it only goes 1/4 of the way in. Is there something I am missing or is it not compatible?

Thanks.

[hickupper]

FYI to anyone who may try this.. the Madbull hop up unit is not compatible with this model.