GHK M4 V2 RIS Full Metal Airsoft Gas Blowback GBB Rifle (Length: 12.5")

"One of the best gas blowback rifles ever made! I bought the 10.5 inch version, I am very impressed with the quality both internally and externally. May pick up another one, the Colt M4 one.
Pros:
-All steel internals
-Steel outer barrel
-Very gas efficient
-Solid receiver
-Green gas magazines are very light
-Great recoil (even better with C02)
-Shoots great
-CO2 and green gas compatible
-Externals are mostly real steel compatible (stock, grip, selector, not sure about the rail)
-Decent range

Cons:
-Rail Wobbles slightly if you take it off (which you have to)
-Mags are very expensive
-Gun is expensive (but worth it)
-C02 Mags are very heavy
-Hopup could be better

Conclusion:
Highly recommend this GBBR for anyone who wants a high end GBBR. Everything is solid and needs very little upgrades, besides the hopup, nothing internal needs upgrading.

"Have to be completely honest, as much as I wanted to be totally satisfied with the GHK out of the box I definitely wasn't. I had a major issue of the bolt not locking back out of the box, but this was fixed (i think) by clipping some coils off of the bolt catch lever spring and unscrewing the buffer tube 1 turn.

OTHER than this issue the replica quality and finish was amazing. Feels like an excellent replica, very sturdy and has a great recoil impulse using CO2 magazines. Havn't had a chance to skirmish with it yet, but have done alot of plinking. Pretty accurate and great range out of the box. Would recommend a stiffer buffer spring.

Next issue I'm running into is that I'm going to have to re-thread the upper receiver to accept AEG spec rails. I'm going to do this using the madbull upper receiver modification tool which is on the way from evike.

So to be completely honest... after spending $520 I expected this gun to be perfection out of the box and me having to put no work into it whatsoever.... but not the case... Hopefully after getting these kinks worked out everything will be running smoothly. I'm sure my first skirmish with it will put a big ol' smile on my face.