Pistol Questions (KJW M229)

[Snarf]

I recently bought a KJW M229 with two extra magazines. I first played with all the functions and levers on the gun (my first GBB), then filled all of the magazines with 0.23 g BBs and Firepower brand green gas. Went out to my backyard to do some test shooting and joyfully blasted out all of my ammo very quickly. The first two mags fired all of the bullets out. The last one had four or so left when the gas ran out. My friend has an M93r that has a bigger mag, but it can fire several rounds of bullets through it without running out of gas. I can't really tell if the mags are leaking. There isn't any noise, but when I filled up the first mag green gas sprayed all over. I think I wan't pushing the needle in hard enough. So is there something wrong, or is the gun just a gas hog? I don't even know if the mags were filled all the way up. I just put the needle in until I didn't here any more hissing. Another minor issue I had was the range. I was using .23s and was seriously only getting about 50 ft range before the bullets dropped horribly. I don't even know if the gun has hop up. If it does, it's not in an obvious place. The accuracy was also atrocious, but then again I was spamming the trigger with one hand and not using the iron sights. If I used the sights the bullet would hit several inches under. Any help here?

EDIT: The weather was clear, sunny, and ~75 F with high humidity and no wind.

[Crapshoot]

Are you using KJW mags?

[Da Vinci - Да Винчи]

I will attempt to answer questions in a problem:answer format

Ran out of gas before magazine was empty:Possibly a cool-down effect on the internals, or magazine if you were just trigger spamming

Only gassing until hissing stops:Try to gas magazines in 5 bursts 3 seconds each.

Possible gas capacity:Commonly used technique is to completely fill with gas, fire until the magazine is cold, fill with gas while cold, and let the magazine warm up. Gas expands in warmth.

Range issue:Probably amount of gas in magazine, see above fixes

Hop up:Remove the slide and look on the bottom of the barrel for a wheel or possibly a small hole for an allen key. I'm not familiar with 229 style hops, but those'd be my guesses.

Again, those are attempted fixes, nothing can be guaranteed to work, and I may not have listed all solutions. Feel free to add anything.

[Snarf]

Yes, I'm using KJW mags and thank you Da Vinci for your input. I'll try those tomorrow.