Velocity Help... out of ideas

[nicmauro]

First and foremost, I will say that I have searched around looking for an answer but have mostly just found the stock/basic info on the topic... timing, springs, input pressure, etc. I have owned and worked on a few autocockers but mostly I have just left them alone if they work well while doing occasional, light uggrades and repairs. That said, I recently picked up an ANS GX3 that was not functional and did a rebuild on internals, degunked a paint crusted trigger frame, etc. I also rebuilt the stock reg with a kit from ANS which didn't match up 1:1 but was able to make it work and it seems to function fine now.

The main problem seemed to be timing and a little fiddling got it cycling and shooting paint. I thought it was all good but then I realized that my velocity was super low. IVG did nothing significant (no chrono at home though so maybe minor changes) and I ran through pressures from about 180 to 400, also testing out IVG/spring tension alond the way. Basically, I could go lower but never really see an increase over what I would guess to be 150 FPS. Tried a couple of springs including lightest valve and heaviest hammer but really no change. I switched out the valve for a Rat I bought for a different project but again, no meaningful change. I tried adjusting the timing again but it seems like the range is pretty narrow on this setup so about a half turn in or a full turn out on the collar causes either misfire or leaking respectively and I am not really getting blowback so it seems right. I switched bolts (I have another GX3) but also nothing.

I have a couple of older, probably heavier, hammers I could try but at this point I feel like I am kind of just shooting in the dark hoping something works. I have also pulled the valve spring out of guns before and may try that here but really, it just seems like something else is up. Could the tming be so far off that it's working but not really?

Ideas? Am I missing something obvious? Thanks!

[boomersruckus]

Id verify the tank regulator output pressure and increase the input regulator on the gun. If you have covered all of the other bases with springs for the hammer and valve, I would try to run a higher pressure going into the inline reg and increase that vs the ivg. Not saying that this is a great idea but its one step in the troubleshooting world that will help rule out or rule in some problems. My evo cocker runs like a dream at a lower pressure than my stock 02 vert feed. As for the timing of the cocker being so far out.... other than the trigger dropping the sear towards the front portion of the trigger travel and the 3 way sending pressure to the ram after the sear drops and towards the end of the trigger travel, what else is there to adjust to time it? Maybe the position of the stem in the 3 way closer to one of the ram actuation holes, how far the trigger has to move to drop the sear and how tall the sear is in the hammer.... Just not thinking that the velocity is timing related. Maybe the regulator on the marker is janky.

[nicmauro]

Yeah,.I should switch out regs just to eliminate that but I have a gauge on both the reg and the front block (for now) and they both read ok. Lug is just catching plus about a turn but maybe that is throwing it off a tiny bit. I didn't check the sear but I didn't notice anything crazy off when I had it apart but I guess I should. Thanks!

[autococker04]

I had a weird situation once where the hammer was rubbing on something and it wouldn’t go fast enough to open the valve enough for a full velocity shot. I want to say it was the trigger plate but I might be making that up.

try to unscrew the trigger frame just a tiny bit and see if that fixes it. Not as a permanent fix but as a diagnostic. Also make sure the hammer is oiled.

[nicmauro]

Worth a shot, thanks!

[Grendel]

Hammer have a dimpled end or not. Some valves do not work well with a dimpled hammer preventing valve from owning correctly.
Hate to bring this up but is the bolt right side up? We would F**k with teammates all the time and turn their bolts upside down and this is what you get everything is fine but low velocity and IVG will do nothing.
In general if IVG is having little or no affect on velocity that means there is something restricting volume of air getting to the ball

[nicmauro]

I believe it is dimpled but I'm also pretty sure both the valve and hammer were stock. I will try a different hammer though for sure. Bolt is stock ANS which I believe works either way as it has venturi inlets in a full circle. Thanks!

[Toestr]

Do you have a good underbore or are you using a stock (probably overbored) barrel? Otherwise are the valve and bolt aligned correctly (I've heard this being a phantom issue before). That's all I can really think of to suggest.

It seems like you think the hammer is maybe not getting a full strike at the valve because the ram is activating too early? Have you tried firing without cycling the pneus?

[autococker04]

I like this idea, disconnect the ram and see if the hammer is doing enough to shoot

[nicmauro]

I will try this next, thanks. Yeah, that is basically my thought but I do have it setup to fire as early as I can before cycling, a little sooner than I probably would otherwise so I wouldn't think the 3 way is kicking in before hitting the valve.

Re valve and barrel, it's has one of those Rats with a huge open port so flow shouldn't be an issue there but I had the stock valve in previously and it was basically the same. Barrel is a freak, bored tight enough to prevent rollouts. Thanks!

[Daltech]

Timing is mostly done without air pressure. Is the marker timed correctly prior to pressurization? I know that everyone that owns a cocker is an expert, so, just sayin.

https://www.angelfire.com/bc/bnbgeckoranch/autotime.html

I read the article above and it explained allot of stuff that I got wrong when I was 14 and had no clue what I was doing, but I still had every single part of my 99’ cocker exchanged with KAPP, ANS and DYE parts.

Sounds like a sweet spotting symptom to me. You have another GX-3, have you gutted both and made side by side comparison????


Ah, shaaat. Now I want a GX-3.

[nicmauro]

First of all, thanks, I totally forgot about the Ravi site but I loved it back in the early 2000s!

Re the sweet spotting, I don't have a Chrono at the house but I went through most.of a tank running it from about 180 to 400 psi out of the reg (in medium increments... 30 to 50 psi at a go) and running through the IVG at each adjustment and never got near full pressure. I did most of it without paint because I could feel the pressure with my hand and it was always super low.

And yeah, they are pretty nice on my opinion but that is a somewhat biased opinion since it was my dream gun when I was 20 and broke 😂

[docfire]

If its has all stock valve and springs the input psi out of a ANS reg should be between 225 and 275. Do not trust the ANS gauge on the reg for setting

[nicmauro]

It was stock but I switched it for a Rat valve and lighter valve spring but the issue remains. I tested the reg in a roundabout way as I went out to play today and had the seal on another reg blow so I put the ANS one on that gun and it ran pretty good. Obviously, that doesn't totally answer whether it was set correctly on the GX-3 but it is operating.

Suggestions on a better gauge?

I appreciate the input!

[docfire]

just ditch the gauge on the reg and plug the hole. Get an old ASA on/off and a 3" dial dry gauge 0-1500 psi

[nicmauro]

Ok, good deal. I actually just saw someone with that as a setup the other day (maybe you?) and meant to do so. Thanks!