Slight drop off issues

[factoid]

So I played my first games of paintballs in a few years today. My classic mag worked beautifully for the most part but I was having some real issues with velocity consistency. I'd go up to the chrono and pop a shot, get 295. Then the second shot would be 271. And these were not rapid fire shots. It was a good second or so between each.

A few things about this Mag's setup that I think might be part of the problem:

It uses microline instead of macroline. I'm getting this fixed, but the local shop didn't have any 90 degree elbows in stock

It's a cheap steel N2 tank. I didn't want to invest tons of cash in a new 68/4500 just yet, so I got a cheap guerilla tank for about 25 bucks. I don't think this is the problem because even if it has recharge problems it should be able to more than keep up with 1 ball per second.

It's got an expansion chamber as a foregrip. I needed a foregrip but didn't have a standard gas-thru. I'm told there's really very little difference between the two in practice.



The obvious stuff I'm going to try: Switching to macroline. Bypassing the x-chamber and going straight from ASA to valve with one piece.

any other suggestions? Something internal to the valve maybe? I just replaced every o-ring and seal in the gun with the exception of the powertube tip o-ring, which I don't think actually does anything except keep the threads tight...there wasn't even one in my parts kit.

This is a level 7 mag with a power tube spring rather than spacers if that makes any difference.

It was playable and I had a great time, I just could tell my velocity was a little all over the place.

[athomas]

How was the paint size for consistency? In consistent paint can cause velocity fluctuations.

[factoid]

It was rec grade paint which isn't terrifically consistent in size, but the guys that were chronoing before and after with Model 98 rentals weren't having too much trouble

I was fairly overbored on my barrel though. If I took the barrel out and stuck paint in it they would roll right out.

[athomas]

If you are overboring, it shouldn't be a big issue barrel wise unless the paint is really bad for consistency such that it is changing size from tight to really loose. That could cause fluctuations.

[Spider-TW]

Perhaps your first shot is actually hot. You might have a touch of reg creep. Is your reg seat fresh (and clean)?

[factoid]

Perhaps your first shot is actually hot. You might have a touch of reg creep. Is your reg seat fresh (and clean)?

I was thinking the same thing. It's brand new reg seat, but I do have a couple others I could put on if it might help.

Are there any other things I should check? When I did a tear down of the marker a couple weeks ago I replaced all the O-Rings and the reg seat from the parts kit. I tore it down as far as it goes and even pulled out the spring pack and reg piston to clean off the piston face, which was actually pretty clean, but I just gave it a thumb polish and greased it a bit with autolube.

Could there be a problem with the velocity adjuster itself? What sort of grease is that nut supposed to have on it?

[athomas]

I never thought of regulator creep. I assumed every other shot was different. What happens when you shoot at 1 second increments? What are the velocity values for each shot when you do that? If they are consistent and lower after the first shot, then regulator creep is probably your problem.

Grease for your spring pack in the back is only to prevent it from rusting. Any good grease will do.

The velocity adjuster can be an issue, but it is usually not the adjuster itself. It is usually a piece of dirt causing it to stick. If it doesn't slide back and forth smoothly, it won't regulate consistently.

Make sure you put the regulator seat oring in properly. It has a front and back. The large side snaps into the back section. Make sure it is a genuine AGD regulator seat. I have seen lots of others on the market that don't work.

Did you replace the bolt spring when you changed the orings?

[factoid]

I never thought of regulator creep. I assumed every other shot was different. What happens when you shoot at 1 second increments? What are the velocity values for each shot when you do that? If they are consistent and lower after the first shot, then regulator creep is probably your problem.

Grease for your spring pack in the back is only to prevent it from rusting. Any good grease will do.

The velocity adjuster can be an issue, but it is usually not the adjuster itself. It is usually a piece of dirt causing it to stick. If it doesn't slide back and forth smoothly, it won't regulate consistently.

Make sure you put the regulator seat oring in properly. It has a front and back. The large side snaps into the back section. Make sure it is a genuine AGD regulator seat. I have seen lots of others on the market that don't work.

Did you replace the bolt spring when you changed the orings?

It needs to be grease, right? Not oil? I should go to the hardware store and get something that is specifically labeled as GREASE? Like lithium grease or axel grease or something?

Should I clean the threads off the adjuster with alcohol before I reapply?


The velocity went something like this when I was at the chrono shooting slowly (1bps or less)

292
271
272
274

It's hard to say how many shots in a row I'd get consistent because after I saw the drop off I was making an upward adjustment on the knob. Eventually I got it to where it was like 293 and then stayed around 285 for subsequent shots which is where the field wants it.

The reg seat is AGD genuine and it's snapped in the right way. It came out of a brand new AGD parts kit I ordered from Action Village. I replaced all the o-rings, seals, etc... throughout the whole marker because they'd been sitting in a closet for 4 years. A lot of them had gone brown over time, presumably because I didn't know you shouldn't use firearm oil in a paintball marker. I've now switched to Autolube and have shot it through the gun on three separate occassions since installing the new o-rings and seals.

Bolt spring is also brand new.

I will try re-greasing the velocity adjuster. Is there any other type of maintenance I should try in the regulator? All I did last time was remove the spring pack (leaving all the black grease on it) and the reg piston. I cleaned the face of the piston off with my thumb and reapplied a bit of autolube to it. Should I try grease on that surface as well?

I am also going to put on the macroline this week, so we'll see if that helps at all.

[Spider-TW]

The reg seat doesn't need a lot of grease or oil, just a film. Rub it between a pair of clean fingers to be sure it doesn't have any dirt, nicks, or hair on it (I have found a couple hairs in regs). Check the reg body where the seat sits and be sure it is clean as well.

Besides the seat leaking a bit, the reg piston can be sticky and just taking a while to get over a spot. Whenever you clean seals and seats, check and clean the metal surface they sit on. The inside wall of the reg gets neglected often and it can build up old lube and o-ring material, depending on the o-ring, lube and usage. After you oil the o-ring, you can use a little hex wrench or toothpick with your finger and slide the reg piston back and forth in the body. That way you can be sure the reg doesn't have a sticky spot, which naturally occurs in the area of normal operation.

Reg deposits are particular to old and well used markers, so mags can get there easily.

[Ando]

I removed that grease crud off of all my classic valves, that crap is nothing but a dirt magnet and stinks like sin. I replaced it with Tri-Flow, which I use for everything now.

[factoid]

Is it unusual what my reg piston took a bit of force to remove from the housing? It didn't just tip out, I had to grab it with a pick. Not difficult to remove or anything, but a little nudging was required.

I will try cleaning it off and re-lubing.

Now that I think about it I did have one O-ring that I didn't replace...the reg piston. I had one size o-ring in the parts kit that I wasn't sure where it went. I thought it was the power tube tip o-ring, but it was too big. That was probably the piston o-ring. I'll change that out, clean up my reg piston and see if I get an improvement.

Should the piston be greased or oiled? I know there's a difference and using the wrong one could cause premature wear.

[Spider-TW]

Is it unusual what my reg piston took a bit of force to remove from the housing? It didn't just tip out, I had to grab it with a pick. Not difficult to remove or anything, but a little nudging was required.

I will try cleaning it off and re-lubing.

Now that I think about it I did have one O-ring that I didn't replace...the reg piston. I had one size o-ring in the parts kit that I wasn't sure where it went. I thought it was the power tube tip o-ring, but it was too big. That was probably the piston o-ring. I'll change that out, clean up my reg piston and see if I get an improvement.

Should the piston be greased or oiled? I know there's a difference and using the wrong one could cause premature wear.

You usually have to push or pull the piston out, not a problem. You do want it to be smooth though (except where it comes across the threads of course).

I usually use oil on the reg piston. I used to use synthetic grease on classics all the time, but I ended up with a big bottle of superlube multipurpose oil for everything else, so I use that. If you end up putting oil in your asa during a game day, it will probably clear the grease off the seal anyway. Grease doesn't cause wear as much as it slows the piston down, which isn't much of a problem on a regular classic. If you keep it lubed at all, you have time to figure out which lube you like. No lube makes one of those cheap used gun deals from an unhappy owner.

[athomas]

Should the piston be greased or oiled? I know there's a difference and using the wrong one could cause premature wear.

It should be oiled. The oil is very light and provides a very thin smooth lubrication on the surface of the oring. The oil also has less of a chance of holding dirt. Grease is only used to coat the metal on the springs to prevent rust. Grease is better for that because it is thicker and less prone to getting blown off by air movement.

Looking at the velocity numbers posted, it looks like a regulator seat issue. I'd check for debris or a faulty seat. As mentioned, it could be something as simple as a hair or a tiny strand of teflon tape.

[factoid]

It should be oiled. The oil is very light and provides a very thin smooth lubrication on the surface of the oring. The oil also has less of a chance of holding dirt. Grease is only used to coat the metal on the springs to prevent rust. Grease is better for that because it is thicker and less prone to getting blown off by air movement.

Looking at the velocity numbers posted, it looks like a regulator seat issue. I'd check for debris or a faulty seat. As mentioned, it could be something as simple as a hair or a tiny strand of teflon tape.

Thanks for the info.

I'll do a full cleaning of the regulator assembly, and I'll switch out the reg seat again. I've got one more brand new one and two that are older but should be in good shape still.

I'll also clean off the piston, change the o-ring and re-grease the velocity nut with tri-flow (pretty sure I have some in the garage)

Is there any reason to ever clean and re-grease the spring pack?

[Ando]

Use Tri-flow on everything bro. All your orings. The oil that came with the mag will gum up if left sitting for a long while (turns a green sticky color). Tri-Flow w/Teflon is money, a little goes a long way and no worries about it turning into jelly. I been using it for a good 5-6 years now with ZERO issues, best stuff ever.

There's always good reason to re-grease the spring pack. By using oil on the pack all that's required is a drop down the Reg vent hole to keep it in tip top performance. I lube it every time I lube the marker before a day of play.

I don't get to play too often anymore unfortunately