inconsistant fps

[magman313]

i got out to the field for the first time this season yesterday and my fps at the chrono was all over the place + - 20fps, this wasnt during rapid firing either. im running an old aa apocalypse reg on my tank at 1100psi, i recently read with a higher input you can get less consistency but i wouldnt think it would be so high, so my question for you guys is how is your fps at a high input? is it time for a new reg? ive been looking for the parts to rebuild mine with no luck. also i did test my fps with my buddys tank running 850 psi and it was perfectly fine.

ps i fell threw a whole in one of the towers at the field and broke my gun before i could try turning the pressure down on my tank to see if it made a difference

[Cyco-Dude]

hmm...well, assuming you were using the same paint for both tests, it would seem that the culprit is the apoc reg...it may be time for a rebuild. i have an rt pro with an apoc 2k reg on it, as well as a ninja tank with a shp regulator on it...i can test using some valken graffiti paint and see what i get using ~1000 psi vs ~800 psi.

i need to order some o-rings so i can service all of my old aa regs. the regulator seat is the same size as the ones for the automag classic valves, but it's a harder plastic material rather than urethane. the apoc regulator piston (and likely all air america reg pistons) uses the same reg piston o-ring that you'll find in automag rebuild kits. i would be hesitant to crack the thing open though unless it was leaking as you would probably have to replace the reg seat, and i don't know if the automag reg seats would work as a substitute.

also, i get +/-10 fps normally (260-280 range).

[magman313]

that would be awesome. and 10fps would be fine but 20 gives me quite a noticeable difference in accuracy. and a question for you, do you get the 10fps difference during rapid fire or while slowly shooting?

[Boltaction]

some Apoc parts for sale on MCB I noticed last week.

http://www.mcarterbrown.com/forums/m...mag-stuff.html

[Cyco-Dude]

that would be awesome. and 10fps would be fine but 20 gives me quite a noticeable difference in accuracy. and a question for you, do you get the 10fps difference during rapid fire or while slowly shooting?

slowly shooting over the chrono, but i'm sure i'd get the same range rapid fire as well.

[Cyco-Dude]

some Apoc parts for sale on MCB I noticed last week.

http://www.mcarterbrown.com/forums/m...mag-stuff.html

some of that is gone (automag valve parts that had two aa reg adjust nuts); that piston with the spring packs is for an agd reactive valve. anyways, that's not really stuff that goes bad in the first place.

[Spider-TW]

You can test the variations from the valve recharge by being consistent with the timing of your trigger release and the following pull.

Also, if paint rolls down the barrel even 1/8", you'll get large variations in velocity. (Detents too loose for the paint.)

[athomas]

The only fps diffence a higher tank pressure will cause, is if you are rapid firing, or at least quickly firing the gun immediately after a trigger release. In rapid fire conditions, a higher input pressure will cause your valve temperature to rise more than it will for a lower input pressure, causing higher velocity shots. When you let the valve sit a few seconds between shots, the temperature will cool and the velocity will go back down. Its a thing that retro valves are known for, so you need to be aware of it. Consistency when operating the trigger should yield consistent results.

If the tank regulator doesn't have a good flow rate or is inconsistent, it can cause velocity issues because the mag valve won't charge fast enough to reach full velocity on some shots and will reach velocity on others. The same thing can happen if the mag valve itself has oring issues or is sticking somewhere. Since you indicated the valve worked fine on another tank, then the original AA Appocolypse tank seems like it might be the culprit.

[Levi]

I've been meaning to post a thread about this for a while, just haven't had the time to mess with my gear. Since we are having this discussion I will post here.

The one X valve I own has a similar issue, I'll get a few shots that are +/- 5fps, then a couple that are 20-25fps low, an occasional hot one too. Not rapid fire either, single shot over the chrono with at least two or three seconds wait time between shots. I'm thinking that I may have a chunk of crud causing the regulator piston to stick. I will be stripping the valve down this week to look. The classic valves I own are all very consistent, +/- 3 to 6 fps is not uncommon using good paint and barrel.

What other areas would be liable to cause an inconsistency issue?

What is the best consistency that can be expected out of an X valve?

[magman313]

I also noticed that my gauge will drop from 1100 to 1000psi too, i thought it was just during rapid fire but it was also shooting slowly, think its time to put my apocalypse on the shelf

[athomas]

I also noticed that my gauge will drop from 1100 to 1000psi too, i thought it was just during rapid fire but it was also shooting slowly, think its time to put my apocalypse on the shelf

It sounds like your apocalypse regulator needs a cleaning. If you like the apocolypse regulator, give it a good cleaning rather than put it away. Regulators need to be cleaned and maintained just like a mag valve. Actually, a mag valve is just a regulator anyway.

What is the best consistency that can be expected out of an X valve?

An X-valve will be really consistent when used with a consistent trigger pull. If it isn't getting consistent operation and the paint is good, then there is something else causing it. Its usually something causing an oring to stick. Even the level 10 can cause this issue if it isn't tuned properly.

[magman313]

Ill give it a shot, just hope it doesnt need a reg seat as i dont know where to get that

[athomas]

I think the regulator seat is the same one that the classic mag uses.

[magman313]

So basically every o ring i need is in a classic mag kit?

[Cyco-Dude]

I think the regulator seat is the same one that the classic mag uses.

same dimensions, but not the same material. i do not know if it would work or not, but i'll test the next time a service an aa apoc reg.

So basically every o ring i need is in a classic mag kit?

no, there are some o-rings (such as the on/off knob and regulator body o-rings) that are unique to the air america apocalypse regulator. the regulator piston o-ring is the same as the agd regulator piston o-ring, and the o-ring that seals off the tank from the regulator (smaller one of the three on the on/off knob) is the same as a regulator seat / lvl 10 o-ring.

if you do take it apart to clean it, do not remove the regulator seat. hopefully everything lines back up once re-assembled. you'll want to tighten the bolts sequentially, in several passes until they are fully tightened:

1   4

3   2

that way it tightens evenly.