Gearbox selection
 

I thought I read in a post somewhere to stay away from the zinc alloy gearboxes. Other than a Pro Win gearbox, which is the best quality V2 gearbox ? I had a Guarder reinforced one but it didn't last very long. Yes, it broke in the weak spot in front of the cylinder. FPS is only around 380.

That'll be tough, since almost any die-casted product has some zinc-aluminum alloy used as the mix.

The Guarder shouldn't have broken at 380fps. What was the condition of the breakage? (ie temperature, were you doing lots of dry-firing, etc.)
What's your piston head/cylinder head?

When I was researching gearbox's before I came to the conclusion that the zinc alloy was my best bet. I only shot no more than 5000 shots if that and the temperature was always in the 80's. It's got the standard Hurricane cylinder kit with an airsoft surgeon stage 3 spring. Also a standard half tooth piston. My buddy has the same style hurricane kit in his AK and has never had problems shooting at 400fps.

380fps is pretty low with that spring. I was able to get over 460fps in my test platform.

But that's off-topic.

Hmm... sounds like your setup *should* have been able to handle that weight. Anyways, I haven't heard of any major issues with the King Arms, G&P or Systema gearboxes.

But I HAVE had tons of problems with the Guarder one. I haven't had much luck with them.

When I picked it up at the shop I asked the guy to fire it through the chrony and he said it shot 383 I believe. I knew that didn't sound right either. I'm going with a G&P metal body so I may just go with their gearbox too.

Sounds like a casting defect to me, it's rare but it does happen. Guarder makes good metal gearbox shells but they seem to think powder coating the interior of the gearbox is intelligent...
G&P makes good gearbox shells as well, 7mm holes for bearings too which is really nice. We've got a guy in Mb who's an absolute hose with his 400fps G&P 249(I mean like 4 bags a game!!), he's had it for pretty much the whole season and he hasn't broken his gearbox shell yet.

is that guy you tc? :P