NPAS, Hi-flows or both? Better gas?

Gaz2010

Just wondering has anybody put the NPAS valve into a KWA or KSC pistol?

Will it do the same job as a hi-flow valve and increase 'recoil' and cyclic speed? Or just fps? Reason i ask is got a steel USP slide and need to up gas flow by a lot!....an awful lot!

Anywhere in Ireland selling red or higher power gases than the crap brands or green we get here?


cheers


EDIT: Wrong section! Mods please move, thanks

c28omzk7ihsxv0

Gaz2010 wrote: »

Just wondering has anybody put the NPAS valve into a KWA or KSC pistol?

Will it do the same job as a hi-flow valve and increase 'recoil' and cyclic speed? Or just fps? Reason i ask is got a steel USP slide and need to up gas flow by a lot!....an awful lot!

Anywhere in Ireland selling red or higher power gases than the crap brands or green we get here?


cheers


EDIT: Wrong section! Mods please move, thanks

I have an N-pas kit in my ksc usp, it doesn't affect the cycle of the slide one bit, just the fps. I can get my BB's from just coming out the barrel (like 70 fps or something) to a very illegal and not used number. I think on the Ra-tech site they put up a video showing it go over 500fps, but of course no one in their right mind would use that. I keep mine at 280 FPS.

Gaz2010

Yeah i watched the vid. At the low setting it looks like the slide moves slower than the high setting. May just be wishful thinking on my behalf. The vid with the steel slide on a usp match yea?

c28omzk7ihsxv0

Gaz2010 wrote: »

Yeah i watched the vid. At the low setting it looks like the slide moves slower than the high setting. May just be wishful thinking on my behalf. The vid with the steel slide on a usp match yea?

I'm not sure I remember. I think it was. Check the description.

Inari

Best thing to do is to add small shims to your magazine gas casket (that piece of rubber at the top of the magazine) so that it creates a better seal with the BBU, and install an NPAS kit.

When you get a better seal on the USP's you need to use an NPAS as you'll likely be pushing the legal limit as it stands. The guns are not rated for higher pressured gases, so personally I wouldn't go there. Green Gas should be suitable, but rather just not very efficient.

High flow valves will just increase the amount of gas used per shot, and lower gas efficiency even further due to increased cool down effects (more rapid changes in pressure due to increased loss of gas). It is my understanding (which could very well be wrong) that high flow valves merely increase the volume and pressure of gas inside the BBU, as it fills quicker, and more gas follows/pushes the BB on the way out, and then the rest rocks the slide back for the blowback portion.

c28omzk7ihsxv0

Yeah, never bother with a high flow valve IMO. It's especially redundant if you have an N-PAS kit in it anyway.

Gaz2010

Inari wrote: »

Best thing to do is to add small shims to your magazine gas casket (that piece of rubber at the top of the magazine) so that it creates a better seal with the BBU, and install an NPAS kit.

When you get a better seal on the USP's you need to use an NPAS as you'll likely be pushing the legal limit as it stands. The guns are not rated for higher pressured gases, so personally I wouldn't go there. Green Gas should be suitable, but rather just not very efficient.

High flow valves will just increase the amount of gas used per shot, and lower gas efficiency even further due to increased cool down effects (more rapid changes in pressure due to increased loss of gas). It is my understanding (which could very well be wrong) that high flow valves merely increase the volume and pressure of gas inside the BBU, as it fills quicker, and more gas follows/pushes the BB on the way out, and then the rest rocks the slide back for the blowback portion.

Is any of this from actual experience or what? Those gas router shims look like a pure gimmick to me. If anything you can just replace the routers with different ones. Plus moving the router up will just cause it to wear a lot faster.

I need MORE GAS FLOW (way more ) or higher pressure gas to cycle a slide much heavier than the stock one! I wanted to know will fitting an NPAS valve effect flow through the bbu or just the amount of gas used to shoot the bb.
Hi flows have bigger ports letting more gas out of the mag every time the striker hits the valve. Dont care about how many shots i get out of a mag, i dont need 20 odd shots per fill.

This is not a stock gun, i've ordered some red gas so time will tell if its any better than green. Failing that i'll file out the ports in the standard valve and see if it does anything noticeable.

c28omzk7ihsxv0

Red gas is a gimmick. It adds very little FPS. It wouldnbe the same as using bottles propane over green gas.

Gaz2010

Got 2000ml bottles for a tenner each so its all good either way! I'll chrono a few pistols and see what if any difference it makes when the bottles get delivered.

A gain is still a gain, the nearer i can get my pistols to 328fps the better!

My ksc is 310 ish so if npas does nothing for the kick its pointless for me at the min.

Inari

Everything I've said IS from experience, as an owner of KWA/KSC NS2 USP Tactical, KWA/KSC NS2 MK23.

By adding shims you're reducing the distance between gasket and BBU, creating a better seal (as mentioned), which results in reduced gas expenditure. It also increases blowback due to the increased pressure inside of the BBU. I made my shims out of pieces of plastic cut with a trusty Swiss Army knife (not everything requires a specific part). You need to use an NPAS kit as it will be pushing the legal limit (my USP Tactical was firing stock at 328fps - literally).

Adding shims is not always an option - sometimes the magazine's gasket will already be at the desired height, however I have found it helpful for some brands, and not on others. It all depends on the magazine itself and how much clearance there actually is.

Gaz2010

I wouldn't bother shimming it as it will wear the router faster. If your going down that route i think its better to get higher quality ones instead.

I'll see if the red gas makes a difference when it gets here

hightower1

Have a USP compac metal slide and I installed a 150% recoil spring - that certainly decreased the slide cycle time while also making the action a LOT cripser and harder. That coupled with the shims and hi output valve for the mags would make a noticible increase in fps but maintain eficiency as best possible.

I have a tight bore insalled too and that massivly increases accuracy , while you have it open I would also recomend that seeing as your there