GHK AKM GBBR - Propane vs CO2

[Greyhame888]

Ok, so I've spent pretty much the last three days searching multiple forums trying to get an answer to a question. Let me start with a small preamble. I plan on picking up a GHK AKMS in the next week or so, but I have a problem. Living in Canada, especially Alberta, weather can be a bitch. Temperature fluctuations on more than 10 degrees in a game are common. Because of this, GBBRs can easily jump or drop FPS. I'm looking for consistency. I plan to use these GHK AKM CO2 magazines.

Because CO2 is generally considered to be more stable and less dependant on ambient temperatures, am I better off to go with CO2? I know CO2 will give me higher FPS, but I also need to regulate that as I want to use this gun both indoor (about 350 fps with 0.2g) and outdoor (about 400-410 fps with 0.2g, absolute max of 425). The only parts I have found so far that seem that they will work are the Ra-TECH NPAS and the FG-Airsoft adjustable nozzle. Now apparently both of these systems should allow me to regulate the pressure, and thus change the FPS, of my AKM.

So I guess I have a few questions. First off, am I even in the right ballpark with assuming either of these choices will work? Secondly, does anyone have any experience with either of these items and C02? If not, is there a better option that will work?

Thanks in advance for any assistance.

*edit* I'll also be installing the Samoon Enhanced Recoil system to the gun that seems to work better with CO2, and possibly the Samoon steel outer barrel.

[GBBR]

I recommend you try out propylene gas, it's also marketed as mapp gas. Its cheaaper than using co2 and it also helps in the cold

[Bois Brule]

Greyhame... I've installed the enhanced blowback kit, am installing a steel outer barrel, and have my CO2 mags on the way.
I'll share my experience with you when I get it.

I also have a steel fire control parts on the way, looking for a steel sear and hammer, and plan on upgrading to a CNC nozzle and hop-up, as well as installing a wide bore barrel to get the velocity back down.

As I understand it, the RA Tech NPAS won't work on the new gen. of GHK, and the FG nozzle won't handle the pressure of CO2. If the wide bore barrel won't bring my FPS back down to playable levels, ill be handing my aluminum nozzle over to my buddy to make my own version of the FG adjustable nozzle.

Hoping to have it all done before the end of summer.

[pum]

Bois, did you end up installing the steel barrel?
I replaced the blowback unit with ease, but having a real hard time with the outer barrel. Some of the pins are just tough to get out.

Also, do you really need to disassemble the hop up unit to replace the barrel?

-H