Velocity

[Dauntless152]

So I booked my valve , no issues what so ever. Tuned the velocity and it was great
but even with my nylon screw it seems the Main velocity screw keeps backing out. Is the nylon worn ? Or should I get a metal set screw ?
Are there any ways I can do a velocity adjustment that’s not connected to the bolt without adding a reg ?

[RedLeaderSB]

So the nylon screw isn’t supposed to lock adjuster in place by torque/clamp load like I had assumed. You thread it in just enough so the adjuster threads cut into it a tiny bit and give it some friction.
I suggest removing adjuster and turning nylon lock screw a tiny bit until the adjuster has more bite when inserted.

[Jonnydread]

Nylon could be worn, but have you tried putting a drop of loctite on it then letting it air dry and re-installing? Usually it just barely stops the threads.

[coyote]

Loctite is anaerobic. It cures in the absence of oxygen.

[Dauntless152]

That makes sense to have it thread into the plastic and not the other way around . I’m thinking my main spring is old too. I was shooting 270 and then 2 games later it was lose and shooting 160

[Chuck E Ducky]

What springs are you running?

Stock Silver springs 1.5-2 turns in from flush should get you in the ball park. as long as your HPA input is at least 800psi or you run Co2/12g.

Also insure your bolt tip oring is intact and your pump rod is screwed in so that it properly seals on the back of the barrel in the forward stroke of the pump handle. Also make sure the valve body is tight and flush with the marker body when reassembled. Also make sure your cup seal didn’t back off and is tight on the power tube. I like a lil light hold loctite on mine.

If your TPC is turned in to far this will cause all kinds of issues. Because it will move around and bind on the main spring.

That Teflon set screw is just there to creat resistance on the TPC. Remove the TPC set the Teflon grub so it just enters the bolts inner bore and thread the TPC into it.