Bit of a problem

[n1ckh]

So...my first outing with my newly tapped masada today (thanks to the guys who've helped me) 

Got to chrono & it's pants. On .25 it was to hot. Lowest I could go was 40psi on the regulator & wouldn't cycle after 1st shot, increase PSI & increased the FPS. 

48ci proto bottle, 8mm hose & HPR800C regulator going to tapped magazines. 

To get within limits now, do I go with an SLP reg or fit an NPAS ?? 

Nick 

Edit....at time of chrono, I was using a 6mm macro line so not to remove the 8mm line from my plate carrier. 

Could the 6mm line make a difference ?? 

 

[Duff]

As I understand it from a bit of Google-Fu, the smaller the line the smaller the PSI variable.

1/4" Macroline is made to operate 500-700 psi with a burst pressure 3-4 times higher.

5/32" Microline can operate from 800-1100 psi with a burst pressure 3-4 times higher.

Most 1/8" Polyurethane tubing operates at about 150-250 psi with a burst pressure only slightly over.

Hope that's a little helpful.

 

[proffrink]

You'll likely need an NPAS if it's shooting hot but not cycling reliably on lower pressures. That said, most tapped setups run at about 60psi with no issues. Going above ~90psi begins to get dangerous for HPA taps as that's when gaskets can wear much more quickly.

SLP regulators work on the input, not the output (i.e. they accept SLP tank regulators that output under ~300psi from the tank). An SLP regulator still aims to output ~40-120psi to the gun. In short, an SLP regulator won't solve your problem.

I know it's stating the obvious but be absolutely sure your cronograph is working correctly. What are you actually getting on a .25g BB?

Also ignore Duff - he's talking about line pressures (that have little to do with this unfortunately). Your line bore will make little difference to actual pressure but will affect flow rate/refresh rate. This could do stop cycling but the easiest way to check is just to fire a shot on semi, then another 3 seconds later (after it's had a chance to 'refresh'). If it cycles correctly then the issue is indeed a flow one, and this is solved typically by increasing your output pressure as most regulators just can't refresh quickly enough at lower pressures (indeed it comes an issue of fluid dynamics at this point). Wider bores can matter on some systems but really it shouldn't be affecting you too much. The only gun I know of that needs wider bore attention is something like the Daytona M249 or M240.

 

[n1ckh]

Thanks for the input as usual prof. 

Using .25 during a game is rated at 312 & the rifle was around 315 or a bit higher. It wouldn't even pass as a dmr. 

I trust the sites chrono to be accurate as they use there own mags & bb's

At home, I upped the pressure to 50psi & it cycled properly so minimum I can go to is 50psi. 

So an NPAS it is then 

 

[Duff]

Also ignore Duff - he's talking about line pressures (that have little to do with this unfortunately). Your line bore will make little difference to actual pressure but will affect flow rate/refresh rate. This could do stop cycling but the easiest way to check is just to fire a shot on semi, then another 3 seconds later (after it's had a chance to 'refresh'). If it cycles correctly then the issue is indeed a flow one, and this is solved typically by increasing your output pressure as most regulators just can't refresh quickly enough at lower pressures (indeed it comes an issue of fluid dynamics at this point). Wider bores can matter on some systems but really it shouldn't be affecting you too much. The only gun I know of that needs wider bore attention is something like the Daytona M249 or M240.

Sorry was just trying to be helpful. His thread had gone unnoticed for almost 18hours so I thought I'd try and help by at least bumping it. I wasn't sure if it was due to the line differences, hence why I didn't post with any certainty.

 

[proffrink]

Noted but remember that bad info is sometimes worse than none at all.

Thanks for the input as usual prof. 

Using .25 during a game is rated at 312 & the rifle was around 315 or a bit higher. It wouldn't even pass as a dmr. 

I trust the sites chrono to be accurate as they use there own mags & bb's

At home, I upped the pressure to 50psi & it cycled properly so minimum I can go to is 50psi. 

So an NPAS it is then 

Not a problem I've heard of before but hopefully you can get it sorted with the NPAS. Should allow you to direct more of that air back towards the blow-back mechanism.

Of course with most GBBRs in theory they're supposed to be using a gas that's still expanding as it hits the nozzle so they can act very differently with HPA (which doesn't go liquid at the pressures we're using it).

 

[sjhirst]

Would the FG Airsoft LFS discs be compatible with the masada?

They are worth a look at if you don't want to use a npas.

 

[n1ckh]

Would the FG Airsoft LFS discs be compatible with the masada?

They are worth a look at if you don't want to use a npas.

I did look at them but they look a bit flimsy & not very secure. It's a good idea & thankyou for your reply. 

I went & ordered an NPAS last night so should arrive the next few days