Need help in resolving spiking issue.

SkinWalk3r · #1 (**permalink**) 06-26-2008, 10:16 AM

I’ve been trying to resolve this issue for a while and have been methodical about it so far. Now I am at a dead end and need help.

My marker fires within acceptable fps limits for the first few shot and then there is +/- 10 fps spike, then back to normal and then again a spike.

The setup is :

- Pure Energy 69/4500
- Palmer Inline Stab apprx set 700 psi. Connected to bottle then remote.
- FVA mod done. RVA pretty much all the way in.
- Red Maddman springs.
- Smooth internals. Not polished to glass like quality. But removed paint and finely sanded to smoothness.
- Newer X7 type valve (came stock)

What I have done so far.

- Tried shooting with above setup and got spikes.
- Removed the Stab and remote and connected bottle directly to ASA. Got higher FPS but still same spiking deviations.
- Used a Freak setup on above both tests. Changed barrels entirely and still spikes.
- Took the bottle and put it on my Epiphany and it works just fine.
- Same paint in Epiphany and it works fine.
- Used stock springs and still spiking.

So at this point I am lead to believe that the problem is one of two things :

Paint ( maybe higher psi is causing problems not seen in Epiphany setup)
Marker itself.

Assuming it is not paint. What else inside the marker could cause these deviations. I have checked and rechecked everything. All O-rings are intact and lubed to the gills. Everything is smooth as far as I can tell. The whole marker is bolted tight only to finger tightness so I can get free bolt movement.

The Spiritus Raptor · #2 (**permalink**) 06-26-2008, 01:32 PM

haha oh god, you and odin should hang out on the weekends... he's in almost the same range as you, and has almost the same setup...... I wish I could help, but he's been chasing ghosts for months now.

thebowtwo · #3 (**permalink**) 06-26-2008, 01:56 PM

To me +- 10fps is good,remember it is a tippmann blowback marker.I would just set the fps a little lower than the field requires and live with it.but thats just me, good luck.

SkinWalk3r · #4 (**permalink**) 06-26-2008, 01:58 PM

Quote:

Originally Posted by thebowtwo

To me +- 10fps is good,remember it is a tippmann blowback marker.I would just set the fps a littel lower than the field requires and live with it.but thats just me, good luck.

true but how are the rest of you getting much more accurate fps. what is different ?

VVulfe · #5 (**permalink**) 06-26-2008, 02:00 PM

thebowtwo's right, that's not bad given what the A-5 is.

How's your paint-to-barrel match? This will affect velocity consistency.

The Spiritus Raptor · #6 (**permalink**) 06-26-2008, 02:05 PM

mine's only +/- 8 and that's with each paintball used hand inspected, using top of the line nelson paint that's only a week out of the factory... in the end, it is a blowback marker it is the least consistant of any design.... it has its limits, that of which you are right on the edge of... which is also what I told Odin.

thebowtwo · #7 (**permalink**) 06-26-2008, 02:08 PM

I reread your post and now I'm wondering if you are not getting some shoot down? try not to turn your remote on as much.just turn it until you get air in the line and go 1 full turn more. also how many shots have you taken with this set up? Is th stabe broken in yet? As VVulfe said your bore match will affect your velocity.

The Spiritus Raptor · #8 (**permalink**) 06-26-2008, 02:20 PM

well, typically when you chrono to get a fps spread, you cannot shoot fast... aka 1 shot and read, one shot and read, etc. Shootdown wouldnt be an issue in measuring spread, but I have seen that too much tension on the rear spring is not good for consistency. You should make your rva as soft as possible actually, as this has an effect on the bolt, and bolt motion (it's attached to the hammer), resistance to the air resetting the hammer, and probably more that I'm not thinking of right now. Excessive pressure on the hammer causes the valve to be open too long, leaving more time for air based inconsistencies, and contrary to belief, the fva matching the powertube really doesn't make a difference. I get a +/- 8 spread, and I have that sucker almost all the way in (about a turn and a quarter from being bottomed out). Also, if you drop your input pressure to right around 700, it makes it a bit more consistent... anything more or less and it seems to make the spread larger.... hope this helps you dude, this is how I got mine to where it is... and its with a CMI inline reg (~40 bucks, but the only other one other than palmers that can handle liquid co2 properly).

thebowtwo · #9 (**permalink**) 06-26-2008, 02:24 PM

Quote:

Originally Posted by The Spiritus Raptor

well, typically when you chrono to get a fps spread, you cannot shoot fast... aka 1 shot and read, one shot and read, etc. Shootdown wouldnt be an issue in measuring spread, but I have seen that too much tension on the rear spring is not good for consistency. You should make your rva as soft as possible actually, as this has an effect on the bolt, and bolt motion (it's attached to the hammer).

Thats a good point,I was thinking more of maybe the remote was turned in to far and chocking the air supply.I had it happen to me.I had my son turn on my remote and he cranked it on all the way and it would not shoot worth a darn, even shooting slowly.

The Spiritus Raptor · #10 (**permalink**) 06-26-2008, 02:28 PM

That's true, some remote lines have that prob.... it has to do with an increase in turbulence leading to the line itself. ASA's are notorious for doing the same thing, that's why i always recommend spending the loot and getting the best ones out there... cuz they will come back and bite you in the butt as far as your markers performance goes... but hey, they do degas the marker!

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode