Originally Posted by MaciekA
Side note, the G&P stick is small enough that I've managed to cram it into a KAC PDW handguard (albeit after some modifcations). Try to spot the Deans-wired 1000mAh battery!
Holy crap! No need for a PEQ box then eh? I'm totally sold on the PDW now....
As for the buffer tube there are 2 types. "Mil spec" and "Commercial spec". Milspec is smaller in diameter while commercial spec is larger in diameter. Googling it milspec is 1.148" dia. while commercial is 1.168" dia. In your case a firefox 7.4V "Short Stick" will work (tested in my G&P M4 buffer tube which I believe to be milspec):
Either that or you can try a 9.9V LiFePO4 battery like this one:
I honestly believe in the LiFe battery, mainly because it can take a bit more abuse than a standard LiPo (it'll probably still catch fire if you stab it with a knife but is less susceptible to undervolting and balance issues) and it's "easier" on the internals of your gun compared to an 11.1V so no more burnt trigger contacts for you. It hasn't gained much traction in the RC world and they're lightyears ahead of us but I think for most airsofters that LiFe is the way to go especially if you're prone to abusing your batteries.