MQ2 Valve horrible efficiency

[Trbo323]

. I'm not sure why all the old threads don't talk more about the horrible efficiency at SON=4ms and why the PBX instructions tell users to raise their HPR to max venting pressure and then back off only slightly.

That advise is pretty dumb as you will no longer have any velocity control. In my experience you do need to run them pretty close to venting pressure but that small area is your velocity control

Also, got a photo of what you are running this on?

[Schroeder]

That advise is pretty dumb as you will no longer have any velocity control. In my experience you do need to run them pretty close to venting pressure but that small area is your velocity control

Also, got a photo of what you are running this on?

See karni porn below. Lol. I said I was going to leave it all stock but I don't think I'm going to be able to resist the urge to throw a different feedneck on it. I've always hated the stock karni neck. I want a freeflow pump arm with wrench flats, a better LPR in the AKA SCM III, a better reg in an AKA sidewinder or 2 liter (open to suggestions here), and I already have a delrin wave trigger. The stock trigger with a more narrow bottom is also something I've always hated on the stock karnivor. A nexus/besales/inception/empire ram with eclipse QEVs is on the list. I want a hybrid iron cross or naughty dogs eye cover, but they're super rare it seems. CCM macro fittings will be coming too. If and when this happens I'm paying the money to have the parts anno'ed to match. It's not going to be one of those cheapo hillbilly jobs where the stock color scheme is molested.

[Trbo323]

Ok, I just wanted to make sure you were not trying to run like a mini front end. I came across a cocker with mq2 that would only shoot 260 because of that

Sent from my motorola edge 5G UW (2021) using Tapatalk

[grd]

Thanks. Vantrepes on pbnation suggested what you have here. I'm not sure why all the old threads don't talk more about the horrible efficiency at SON=4ms and why the PBX instructions tell users to raise their HPR to max venting pressure and then back off only slightly.

A SON of 4 is standard for mQs and should work fine. The PBX instructions do not say that. Velocity is set with the HPR.

[Schroeder]

I had to report back, so others could learn. I removed my MQ to lube the poppet since vantrepes suspected it may be sticking based on my description of some of the issues. I polished the inside of the brass valve body with a polishing wheel on a dremel. It did a fantastic job. The main cause of the issue was that I did NOT have my poppet spring in place. Pretty embarrassing to have made such a dumb mistake. The balanced valve design will close the poppet and the gun will behave as normal- for the most part. The air filling up behind the poppet and closing it must take much longer without the poppet spring though. During this prolonged period air is venting out down the barrel. I would think I would have been able to lower my dwell to nothing because the lack of a spring was effectively doing this (I think). I'd think my HPR could have been set very low, and I'd still be shooting super hot. This wasn't the case though. I still have tuning to do, but it's really, really close. I used this for an entire day of play. Issues I had with ball breaks may have been due to crap paint because I also had hopper issues that were 100% due to crappy paint. Here's where I am at. I do not have the white spacer installed. I do have the poppet spring installed. lol. Also worth noting; I went one size down on both o-rings on the valve body. I really tightened up the back IVG screw to hold the solenoid housing against the valve body and it still barely aligned the valve body hole with the hole in the top chamber and bolt.

SON= 3.5ms
CDEL= 5.6ms
CON= 28ms
COFF= 26.5ms
tickler LPR is turned up pretty high. I fiddled with that off and on through the day. I have an inception designs LPR I'll be replacing the tickler with.

Thanks for the help, Vantrepes. I hope me documenting this mistakes prevents others from making it.

[grd]

Lol you were talking about the poppet spring on FB so I assumed you had it in there, though the thought did cross my mind.