VFC G3A3 - Increasing gas efficiency to reduce cooldown?

[SmoothboreSten]

I've got a VFC G3 that I'm really very happy with. I've replaced the barrel with a 6.03 and hop-up bucking and it performs really well as DMR aside from one aspect. If I get into a longer engagement, the magazine cool-down becomes an issue towards the end of the magazine. I'm hoping there might be a way to improve the gas efficiency such that I can turn down the NPAS, thus needing less gas to hit to still hit 1.88j with 0.32g bbs.

Here is a video of the kind of thing I mean, using a fresh magazine over the course of about three minutes you can hear the bolts cycle slowing down. I only reloaded because I was worried it would stall.

So what are some options I could try? The barrel is 455mm long, I know that can be an issue with AEGs but there isn't the same barrel volume-to-cylinder volume factor on a GBBR. I could go to a tighter bore? I tend to use Red gas already, perhaps that is exacerbating the cooldown? I'm planning to replace the stock NPAS with a Waldo Dynamics one, more because of the stock being picky about what 1.5mm Allen keys will fit (maybe a burr or fouling in the grub screw).

Any suggestions are welcome, thanks in advance.

 

[Shotround]

check all our orings on the nozzle/bcg (if you pull the nozzle out, cover it with your thumb and push back in it shouldn't go anywhere, or VERY slowly, if it does consider replacing the orings and lubing according (superlube)
could consider doubling the orings on the nozzle plug or replacing with an after market one, or replacing the nozzle Oring with a slightly thicker one (just gotta play around with it)
check hammer isnt causing light strikes or odd strikes
are you filling your mags to the correct amount? over filling will give the hammer a harder time and could lead to less gas per shot
mapp gas (red gas, just make sure no silicone)
crimson npas (waldo and bristol base airsoft) is very good
go to a 6.02
lighter hammer spring
light recoil spring

i wouldn't go lighter bolt carrier, there is a trade off where going light doesn't really work, but if you "Winterise" the gun it should in theory increase your efficiency all year, I just wouldn't use a winter recoil spring & map gas in the summer.

valves are (IMO) very good out of the box these days, but you could try swapping it out to a different valve and see what you get.

i cant say i hear any different, id suggest the G3 section on the HRC discord tbh.