Velocity problems with AKA Tornado Valve.

[PlawB]

I can't get my cocker to shoot above 220 fps. I mean, I can get it up to 270 if I have the HPR pressure at 500 or 600 with the IVG cranked all the way in, but of course it's highly erratic at that range. From 100-300 PSI, best I can get is 220 FPS.

I followed the steps I found in some ancient threads. I put the HPR at 100 and the IVG at 1.5 turns in. I have a heavy hammer spring and a light valve spring. I turned the HPR up bit by bit but could only get to 220. I also tried it with a heavy hammer spring and a medium valve spring, but same issues.

It's a system X cocker, PE ram, Sledgehammer LPR, Bomb 3 way, Custom Products HPR, and of course an AKA Tornado Valve.

With a stock valve I had no problems with my FPS.

[jk88]

G!!! I'll give you a call. I can come by a little later today and we can take a look at it.

[maggot]

Check that the valve is oriented correctly: that when cranking down the jam nut that it didn't accidently turn the valve to the point the holes don't line up well.
Confirm you really have a light valve spring. On a couple of kits I bought years ago the "light" valve spring wasn't light at all.

[PlawB]

Hmmm valve might be a little off center. I always tighten the valve lug before I tighten the jam nut. But it might be a little off.

Valve spring is from a maddman kit and is definitely the lightest of the three. I'll dig out a stock spring and confirm it is lighter than that. But I've got the right springs, right? Heavy hammer, light valve?

[maggot]

Yes, heavy hammer light valve is the right place to be when trying to get velocity up. I had a knockoff maddman kit once, paint was shinier color, where all springs were virtually the same strength and the green were not light at all. If you have a postal scale you can place the spring on it and push down until the spring is compressed to get an idea of spring rate.

[BrendanB]

bolt upside down?

For starts with your lower tube with medium valve spring 300psi on the HPR and make sure ur hammer is not abnormally light and use a med/heavy hammer spring.
Make sure ur paint is bore matched to a barrel and your bolt is not upside down and fitted with proper orings if it has slots for orings.

[PlawB]

What maggot said about a knockoff maddman kit may be what I'm dealing with here. I bought the kit so many years ago on ebay, I have no idea if it's real or not.

I noticed that the valve spring did not actually sit tight on the cupseal. So I had to put the valve spring into the gun loose with the valve following behind it. I was worried that if the spring didn't seat on the cupseal then it wouldn't act right.

Anyways, I replaced the tornado valve with a stock valve. I couldn't find the stock valve spring so I used the maddman blue spring. Still didn't sit tight on the cupseal. I had the same velocity problems.

I took a valve and spring out of an old 2k3 body I have, put it into my gun with a stiff ID hammer spring. I am now shooting 290-300. Sure, the pressure on the HPR is about 500 or more. And the IVG is cranked in a lot. But it's shooting and it's consistent. At some point I may try putting the AKA back in but I'll wait until I get a full and true spring kit for that.

[maggot]

To solve for making sure the valve seats on the spring, hold your cocker tool vertically and put the jam nut, valve, and then balance the spring on the valve stem. Hold the body vertically too and carefully slide them all up into the gun together.