Automag problem (first shot hot?)

[nak81783]

Had a 9+ hour drive from MI to MO to visit my brother. Just getting back to this.

All AGD valves are very robust regulators. Theoretically, all other things being equal (e.g., paint to bore match or lack thereof), any given setting on the velocity adjuster should result in the same velocity, regardless of input pressure. There may be some small nuances to this, but the point of a regulator is to control the input into something consistent and usable. Looking at the other end of the spectrum, say when your tank falls below 900 psi, the velocity won’t drop until you’re below the dump chamber pressure required to achieve that velocity. You’ll lose trigger reset force and have to shoot slowly (lack or recharge), but velocity should hold until about 550-600psi, if I recall correctly. So even though input pressure is below 900psi, velocity doesn’t drop.

Obviously, it’s best to fix the tank, but I’m not sure that was your issue.

Going back to the barrel (sorry, I’m fixated on that still), given the fix you implemented, it shouldn’t be hard to recreate the issue. The o-ring should only be there to keep the halves from coming loose, not for alignment. If you take the o-ring and Teflon tape off, is the barrel misaligned? If so, is there a lip/dam when looking down the barrel from breech end to tip end? If so, I’d shoot some paint through that in a different marker with a good tank.

Let us know results. Thanks.

Edit: Forgot to comment on the heat affecting velocity. This is from the valve’s extremely fast recharge rate. When the air first enters the dump chamber, reaches regulated pressure, and seals the reg seat, the air in the dump
chamber is at its hottest. The air cools, losing pressure, but only to a certain point until the shot is taken. I forget the exact numbers, but for example, shots taken at 15bps might be at 300fps, 10bps at 280, and 8bps and slower at 250fps.

This is why there is a chrono procedure for RT/X-Valves. Shoot and hold trigger back, position marker over chrono, release and pull trigger as quickly as possible. This simulates the velocity during rapid fire. If you chrono with normal single trigger pulls, you’ll likely see a 20-30fps drop compared to the rapid fire simulation chrono procedure.

[nak81783]

Found it! See pages 6-9 as pages are numbered, 8-11 of as PDF is numbered.

https://www.orings-online.net/docume...One.Manual.pdf

My numbers were off, but general idea was correct. I also left out that after enough time of the air cooling, the reg will open back up to stabilize the reg close to peak pressure/highest, rapid fire velocity. Apparently that is around ten seconds.

[rawbutter]

Found it! See pages 6-9 as pages are numbered, 8-11 of as PDF is numbered.

https://www.orings-online.net/docume...One.Manual.pdf

My numbers were off, but general idea was correct. I also left out that after enough time of the air cooling, the reg will open back up to stabilize the reg close to peak pressure/highest, rapid fire velocity. Apparently that is around ten seconds.

Thanks for looking that up. I've been using a stick feed for the last year or two, so I don't generally shoot fast. But I do often shoot quick two-round bursts. I guess that would mean that if I'm shooting fast enough for that little burst, the first shot will be cooler than the second, and I'll have a big variation in FPS. Interesting. I'm also pretty sure that when I chronoed, I wasn't doing it the "right" way. I guess I was so focused on all the other things that might have been wrong that I didn't pay attention to how I was pulling the trigger.

I'm busy the next few days, but I can recheck my chrono speeds later this week. I can un-fix the Ultralite barrel and do some more test shooting then.

[rawbutter]

Okay. Update time.

"Unfixing" the Ultralite barrel made me break paint again, even in a different marker. So that was definitely part of the problem before.

However, and I also double-checked my velocity the right way---shoot, hold the trigger, then release and quickly shoot again. Doing that, my fps was much higher. There were plenty of shots over 300. Then when tested my fps the "wrong" way by releasing the trigger and waiting a few seconds between each shot, my fps was much less consistent and much lower in the 260-280 range. That's like a 30 or 40 fps swing. In the past, I've tried to chrono this Automag at 275ish, but since I was doing it the wrong way, that means my actual fps could have been up to 315. Add in the crooked barrel, and that's not a good environment for paintballs.

Now my Automag is chrono'd the right way at 290ish. That does mean that occasionally I'm getting a shot coming out at 250, but that's fine. I'm overboring and shooting mid-range paint, so I don't know if I can really expect much more. Besides, most of my shots are in the 270-280 range, so we'll just have to call it good enough.

[Brokeass_baller]

I admire the engineering of the RT valves, but that FPS swing is exactly why I prefer Classics.

[Jordan]

Same... every time I read a "what's wrong" thread on AO, Facebook, or here, it involves an Xvalve and/or ULT.

[rawbutter]

Well, crap. I've got a ULT in there too. Lol. Don't know why. It's a pneumag, after all. Doesn't make any difference. I just never bothered to take it out.

[nak81783]

Glad you got it working. I’ve posted elsewhere something to the effect that average paint these days is about a 30fps swing. I’ve had crappy paint be as high as 80fps swing. I know the markers are fine, because they hold less than 8fps spread with a single nylon .6875 ball out of a .685 barrel with the same ball recovered and reshot every time.

Add to that the 25 or 30fps spread of the X-Valve, and you’re right in the ball park.

Renewed calls for aluminum Classic valves? I know it’ll never happen. But I’m also considering dumping the X-Valve and just keeping my Classic.

[Jordan]

If it's weight you worry about, capping a Classic valve and running an external reg doesn't necessarily reduce heft but does relocate it so it feels lighter... my Micromag feels great set up with a female Stab and capped valve.

[rawbutter]

Glad you got it working. I’ve posted elsewhere something to the effect that average paint these days is about a 30fps swing. I’ve had crappy paint be as high as 80fps swing. I know the markers are fine, because they hold less than 8fps spread with a single nylon .6875 ball out of a .685 barrel with the same ball recovered and reshot every time.

Add to that the 25 or 30fps spread of the X-Valve, and you’re right in the ball park.

Renewed calls for aluminum Classic valves? I know it’ll never happen. But I’m also considering dumping the X-Valve and just keeping my Classic.

Yeah. I'm not sure what I'm going to do either. I've always told myself that this is my forever marker. I love the way it looks, the way it feels, the way it shoots. Well, the smoothness and crispness of the shot, anyway. But if the fps on the x-valve keeps oscillating between 250-300....honestly I don't know if I want to keep using it. I might start using my back-up Gmek as my primary and only keep the mag as a backup.

The only reason I might keep using it is because of the "challenge" factor. I'm already handicapping myself with limited paint and 10-round tubes to keep things more interesting. Maybe if I think of this as just another kind of handicap, I can trick my brain into not getting pissed every time I get a slow shot.

The tinkering inside of me also is also wondering what can be done to fix this. Expansion chamber? Low pressure mods? What is it about the classic valve that makes it more consistent than an x-valve, and can I mod the x-valve without ruining it? Hmmm....

[Siress]

The issue I remember is that the reg springs wear on the inside of the cap - so much so that I've seen them deep enough to feel without looking and without using your fingernail. That sort of issue can lead to wild swings in velocity. I'd cap it and put a more reliable regulator on there.

[nak81783]

Capping an X-Valve would turn it into a Classic Valve, the air being regulated before getting to the on/off pin. The side vent hole mentioned earlier would also be an issue. Plug it or the cap would have to hold open the reg seat but leave the two orings on either side of the vent hole in position.

[rawbutter]

Capping an X-Valve would turn it into a Classic Valve, the air being regulated before getting to the on/off pin. The side vent hole mentioned earlier would also be an issue. Plug it or the cap would have to hold open the reg seat but leave the two orings on either side of the vent hole in position.

Sigh....That would kind of ruin the aesthetics I've got going on. Half the reason I love this gun is because of how pretty it is. Plus I'd have to replace my custom foregrip with a reg. I don't wanna do that either.

The issue I remember is that the reg springs wear on the inside of the cap - so much so that I've seen them deep enough to feel without looking and without using your fingernail. That sort of issue can lead to wild swings in velocity. I'd cap it and put a more reliable regulator on there.

Interesting. This I can work with. I'm pretty sure there's enough room between the springs and the inside of the cap for a Delrin or brass bushing. That would be easy to make on my lathe. I could try that out and see if that helps with the rubbing.

Or....OR....what about replacing the coil springs with a Belleville washer spring pack? That's what the classic valve uses, and Belleville washers are more reliable and consistent than springs.

[Siress]

I like the idea of belleville washers instead of the spring. Let us know how it goes!

[nak81783]

You should replicate my nylon ball chrono test to see if your marker is actually inconsistent before modifying or adding parts to your marker.

I worked on a different marker last night with the chrono, so I decided to repeat and add to my previous chrono test of the Automag.

Slow fire velocity (about as fast as I could recover the ball and shoot it again): 5 shots, 263-268, let’s call it 265 fps

Rapid fire simulation method: 5 shots, 293-299, let’s call it 295 fps

So a definite increase with rapid fire. I then did 3 shots each with 10, 20, 30, and 60 second intervals to see if it would get up to 295 (rapid fire fps) like the manual states. It never did. It only increased to a max of 271 fps.

Slow rate of fire shots being 30fps slower than rapid fire may be an issue during play, but the marker is in line with my others in terms of consistency.

[rawbutter]

You should replicate my nylon ball chrono test to see if your marker is actually inconsistent before modifying or adding parts to your marker.

Yeah, you're probably right. I can afford $20 for some nylon balls. I'll try that out first before doing anything else.

[rawbutter]

Next chapter to this story is kinda poetic.

I got to play yesterday. It was really cold. Like, 34 degrees when we started, and it only got up to 45 by the time we were done.

I brought a whole bunch of different guns. My Emeks. A Gtek. Two Minis. A new-to-me M170R that I just bought to perhaps replace the Automag. And the Automag, of course, though I didn't plan to use it.

We were playing with Valken 'Merica. It did NOT like the cold. You could throw the balls at a tree and get them to break.

We started playing anyway. The M170R broke paint in the barrel within the first ten shots. Most of my loaner Emeks broke paint. The Mini broke paint. Another friend brought an Autococker, and he broke paint.

Oddly, the only other guy there with an Automag didn't break paint that first game. And I was so busy helping other people clean their guns that I didn't have time to clean the M170R before starting again, so I grabbed my Automag.

And it worked. Sweet baby Jesus, it worked all day. I spent all my free time between games helping other guys clean out Emeks and Minis and Autocockers and the M170R. But the Automags just kept on working.

I did eventually get a bad break right at the end of the very last game. I didn't have a paintball gun after that. It was a blunderbuss. And the guy with the one other Automag had one break during the day. But overall they faired better than anything else out there yesterday.

Maybe I'll keep the Automag after all. I did spend all that time straightening the barrel and rebuilding the tank regulator, and I just replaced the foregrip. Can't sell it too soon, I guess.

[nak81783]

That’s been my experience. The Mags can shoot outside later into the cold season than all my other stuff. I get hung up on numbers once in a while. Truth is, I’ve been shooting Mags for over two decades mostly without issues.