A gas effiecent GBB pistol

Ok so my dad said that he would buy me a Gas blowback pistol..Im looking for a gas efficent..not a gas hog pistol.I have the KWA Kp8 .45 with the Ns2 thing in it..Or the KJW M1911 tactical..im open to any recommendations for a gbb pistol..My max limit is 140$..

The KJW 1911 would be gas efficient with the Co2 mag and so-so with the green gas mag. If you want an efficient one get a plastic slide. My friend had a KWA M9 with a plastic slide and it would get maybe 3 mags out of a charge of gas.

I would look at the WE 1911 for $105 it comes with the gun and an additional magazine.

http://www.airsoftgi.com/product_info.php?cPath=139_25_130&products_id=1729

Or go with this KJW M9

http://www.airsoftgi.com/product_info.php?cPath=139_25_151&products_id=3134

But in the end its really up to what you like best. Also like Hobobob said if your looking for a really efficient magazine go with a Co2 mag even though the Co2 mag is more expensive in the end its a real money saver. Not to mention Co2 is only .50cents for a little cartrige your probably going to get two full mags out of and Co2 shoots harder than green gas.

whats cheaper than both is propane with an adapter thats what me and my bother use. it's green gas without scent and it's only $3 for a pack of 2 cans(huge cans bigger than the green gas ones about twice the size)

Propane is cool. I need to grab an adapter for my 1911 in my next order from Airsoft G.I.

after i trick out the MP5 i'm gonna et a gas gun maube that 1911(top one)

My friend was thinking about that I believe. I think hes gona get this one instead though...
http://www.airsoftgi.com/product_info.php?cPath=139_25_130&products_id=4254

I am going to get a kwa kp8 45 here soon. unless the new mp7 gas by kwa catches my eye. also on the kp8 45, should i get the compact version or not.

I would go for the full size version just because its massive haha. If you need it to be small go for the compact one.

Well i like the size of the 4.3 hi capa, and i was looking for something around that size. And i love KWA.

The Hi Capa is closer to the compact size I think then the full size USP. You could always try one of their Glock like the 18 is close to that size or this one...
http://www.airsoftgi.com/product_info.php?cPath=139_25_63&products_id=3911
Kinda looks like the Hi Capa

Well i think i am going to go for the compact size then.