[barrel roll]

Summarized - Operating pressure is well above the 190 psi everything says to adjust the HPR to. I also couldn't get any better than about 260 FPS with a .678 barrel and it sounded like a Tippman X-7 when I'd shoot off a string of paint.

The marker is freshly rebuilt (software), dwell is set at 12ms, LPR is flush, brand new schrader valve purchased at Cup (Thanks again to everyone at the MacDev booth).

*I will pull apart the lower tube and relube all o-rings except the bumper on the back of the hammer.

*I read somewhere about someone's solenoid needing a cleaning, and that caused his high operating pressure and low velocity, so I will be pulling that apart.

*I'm going to be checking the bolt pin, to see if it is starting to come out. Give it some light hammer love.

Anything else I should look into?

[Zippin35]

My 2 go two's were the hammer and schrader valve so you've got me stumped. Where is your lpr set to? Flush or turned in a bit, if it sounds like an X7 your lpr may be turned in too much.

[poopresearch]

My RX was super pick about ram switch oring fit. Try replacing that oring.

[ghost271]

Leave the HPR at 190-200 and then adjust the LPR to increase fps. If you are off by 15-20 fps then up your dwell. If you've rebuilt and put in fresh o-rings then things need a bit of time to wear in. Dont go pulling things apart just yet. Most times its the simplest thing that you've overlooked.

[The_Fresh]

i had this problem after i put in my pooty modded bolt. i kept cranking the dwell and hpr and lpr to see if i could get the gun to shoot higher than 270 and nothing worked.
ended up being we had the wrong o rings on the bolt (had to go to smaller size o rings (014's) since the o rings were creating too much drag. now i know this isnt probably what happened but if i was you i would want to is rebuilt the drivetrain with fresh correct size o rings. assuming you have no leaks the rx runs like 180-200psi and a flush lpr. use the hpr to set fps. set dwell to 10. anything higher is a waste. you can tone the dwell down after its all broken back in. go a little higher on bore on the barrel .678 might be creating major drag. try a .685 or a 689

[Zippin35]

^^Well if he knows the HPR is running well above what it should be and the FPS is well below what it should be, tuning the FPS with the HPR will likely result in some over pressurization. Now that you mention it though, I once ran into issues with a poorly sized bolt tip o-ring so OP I would check that, especially as it is one of the few moving o-rings in the gun.

[barrel roll]

Ok, ram switch replaced. The back two orings on the bolt seemed to be 015, so I replaced all 3. The bolt pin got some hammer love. I'm holding of on clean/lube of the solenoid. I'm lowering the dwell back down to 10, even though I swear someone from MacDev said 12 for break in.

Now I need to reset the HPR to 190, then check velocity.

About the under boaring, do you really think that is an issue? My cockers seem to be fine with it.

[The_Fresh]

Originally Posted by Zippin35

^^Well if he knows the HPR is running well above what it should be and the FPS is well below what it should be, tuning the FPS with the HPR will likely result in some over pressurization. Now that you mention it though, I once ran into issues with a poorly sized bolt tip o-ring so OP I would check that, especially as it is one of the few moving o-rings in the gun.

the hpr is high from him. he set it that high to see if the fps would go up.

Originally Posted by barrel roll

Ok, ram switch replaced. The back two orings on the bolt seemed to be 015, so I replaced all 3. The bolt pin got some hammer love. I'm holding of on clean/lube of the solenoid. I'm lowering the dwell back down to 10, even though I swear someone from MacDev said 12 for break in.

Now I need to reset the HPR to 190, then check velocity.

About the under boaring, do you really think that is an issue? My cockers seem to be fine with it.

underboring isnt a problem at all just creates a bit of drag. not to create a problem like what u r experiencing. i wouldnt touch the noid it should be ok. ya set the dwell to 10. re chrono that ***** and see if it fixed it. DUDE replace the back bolt rings to 14's that was my problem with my pooty bolt. do you have a gold bolt or regular? if its gold bolt run a 014

https://www.pbnation.com/showthread.php?t=3045987

[barrel roll]

I love gooooooooooooold

The wife says it is too late to play paint wars in the backyard. Chrono tomorrow,I guess.

[The_Fresh]

well you are the one with the gun, so she must obey

[Zippin35]

Originally Posted by The_Fresh

the hpr is high from him. he set it that high to see if the fps would go up

https://www.pbnation.com/showthread.php?t=3045987

We'll regardless of who put it high, using the hpr to raise the fps will mean more pressure in the gun. If the hpr is high and the fps* is low then using the hpr to raise the fps will over pressurize the gun.

[The_Fresh]

Originally Posted by Zippin35

We'll regardless of who put it high, using the hpr to raise the fps will mean more pressure in the gun. If the hpr is high and the lpr is low then using the hpr to raise the fps will over pressurize the gun.

ok i think i know whats going on. I think im confused by the original poster. i assumed he set the gun to 190psi or higher in an attempt to compensate for low fps.

so barrel roll your exact problem is low fps with spiking or raising pressure? or did you set the pressure that high? can you turn it down and its ok? whats your LPR set to? is it flush?

[barrel roll]

LPR flush

HPR originally set to 190, low velocity when firing.

Raised HPR considerably to increase FPS to a playable speed.

[Zippin35]

You sure the schrader valve is good? I had the exact same issues and it was the schrader. I know you said it was replaced but any chance it was a dud? Do you know how considerably you cranked the hpr by chance? Try to set the hpr to 190, lpr a quarter turn in. You mentioned the back 2 o-rings on the bolt as well, just to clarify is it a pooty?

[barrel roll]

Pooty modded gold bolt. The Schrader valve was from the Macdev tent at cup. I got a second one from them, I'll try throwing that in.

[SHOOTNPOO]

Oh the one you said u lost??

[barrel roll]

Originally Posted by SHOOTNPOO

Oh the one you said u lost??

Yep, that's the one! Thought I lost it for good, but it was hiding in the pocket of my shorts, in my laundry bag.

[The_Fresh]

dude i just had this EXACT problem right after i got my pooty modded bolt. i couldnt get the fps to go up for ****. i raised the hpr so high and thing sounded like a cannon and wouldnt go above 270fps. pooty put 015's on the 2 new o rings on the back of the bolt. i switched to 014's and it solved my problem. which is what he recommended and its fixed.

[ghost271]

The problem is you're trying to raise your velocity with your HPR instead of your LPR. You want the LPR flush INITIALLY to see what your baseline FPS is then you adjust the velocity with the LPR.

I've had this problem when I've been using guns for awhile that adjust the velocity via HPR (cocker, Droid) then when I've gone back to my RX I start adjust the HPR and get velocities all over the place. Once I realized what a moron I was, i set it properly and rock and roll the rest of the day.

[barrel roll]

Looks like the orings were the culprits.

.684 Kaner barrel, flush lpr, hpr set to 190, and old paint got me 165 +-4

[ghost271]

So you figured it out then ?
By turning the LPR another 3/4 turn should get you into the high 280's.