Old mag User-Returning after 10 yrs away

[MFM-70]

All,
I have been away from paintball for about 10 years and now we are coming back with a vengence.

Trying to upgrade my 68 Automag and need some help from those who are up on the tech.

QUESTION #1:
Can I drop in an R/T on/off valve into my A.I.R. valved marker and still shoot Co2?


Looking to lighten my trigger pull by 1/2 as some other posts have stated.
I do not care about R/T-ing, as we play fun woodsball.
I am a MoldMaker by trade, so modifying the on/off does not scare me.

QUESTION #2:
If the answer to question #1 is yes, what mods do I have to do to get it to work if any?

Thanks in Advance

[BigEvil]

Welcome back, glad to see you fell off the wagon!

The retro valve is meant for HPA air ONLY. (as are the Emag valve and Xvalve). Is converting to air completely out of the question? It is a vast improvement over c02even on your classic valve.

If you cannot switch, there are two things you can do to lighten that trigger up.

First, and easiest, would be to switch to a RT on/off assembly. You may have to tinker with the size of the pin to get it to workk (I have found .750 seems to do the trick) but it will reduce your trigger pull weight.

The second option would be to look into Pneumagging the gun. There is a lot on that topic around here so just look around a bit for some info.In a nutshell, it is using pnuematics to actuate the sear of the gun, which reduces the trigger pull to near an electro. It can be expensive to do and requires a little savy on the topic to build it the best way.

Look up threads by Loguzzzzzz and Cyberave68. They do a lot of pneumag conversions.

[MFM-70]

Thanks for the quick response.

The assembly I bought is an Rt on/off.
The pin measures .750 on the nose.
It seems as though the gun is coughing when the trigger is pulled instead of the "popping" sound it makes with the origininal onn/off installed.
Also, after 3 quick shots the pressure drops significantly. (by ear)
I have tried turning up the velocity and it seems to improve but still get severe pressure drop.

I would like to stay with Co2 as that is what our entire gang shoots and I have a 15 lb fill tank for this.

This is exactly what I bought:

http://store.airgundesignsusa.com/index.cfm?fuseaction=catalog.prodInfo&productID=399&categoryID=23

Did I get the wrong one?
If so, please send me the link to the correct part.
Thanks

[BigEvil]

Hmmmm interesting. I run one of my mag pumps on co2 with a RT on/off and dont get this issue. Check to make sure that the gap between the trigger rod and the back of the trigger is about thethickness of a matchbook cover when it is aired up.

[MFM-70]

Hmmmm interesting. I run one of my mag pumps on co2 with a RT on/off and dont get this issue. Check to make sure that the gap between the trigger rod and the back of the trigger is about thethickness of a matchbook cover when it is aired up.

I will do this, will be a few days though for other reasons.

Thanks

[fhawkeye]

Thanks for the quick response.

The assembly I bought is an Rt on/off.
The pin measures .750 on the nose.
It seems as though the gun is coughing when the trigger is pulled instead of the "popping" sound it makes with the origininal onn/off installed.
Also, after 3 quick shots the pressure drops significantly. (by ear)
I have tried turning up the velocity and it seems to improve but still get severe pressure drop.

I would like to stay with Co2 as that is what our entire gang shoots and I have a 15 lb fill tank for this.

This is exactly what I bought:

http://store.airgundesignsusa.com/index.cfm?fuseaction=catalog.prodInfo&productID=399&categoryID=23

Did I get the wrong one?
If so, please send me the link to the correct part.
Thanks

I'm assuming that you upgraded to the r/t on/off but not to the r/t rail? If you haven't I have found that when using the am/mm rail with the r/t on/off you will experience severe down-shoot unless your tanks output is above 850psi.

Don't know if this would help in your case. I've got a ULE mag x-valve with the ule on/off that was having downshooting complications on the am/mm rail, that it didnt have on the r/t rail. the problem went away when i turned my tank up to about 900.

[athomas]

Any problem that could be caused by pin length and assembly placement due to rail differences can be fixed by adding a level 1 shim between the two halves of the on-off assembly. It will effectively shorten the pin by .01" allowing for better air flow. If the pin length is determined to be the problem, you can file the small end of the pin so that the pin is shorter.

[MFM-70]

Any problem that could be caused by pin length and assembly placement due to rail differences can be fixed by adding a level 1 shim between the two halves of the on-off assembly. It will effectively shorten the pin by .01" allowing for better air flow. If the pin length is determined to be the problem, you can file the small end of the pin so that the pin is shorter.

I have re aired the marker and found that the gap between the rod and back of the trigger is about .030" Should I adjust this and if so, which way?

I can grind .010" off the pin no problem, but which end?
I assume we are talking about the new R/T pin.

I will be bringing the marker and air to work tomorrow so I can cut and test the shim theory.

Thanks all.

[athomas]

The 0.03" is pretty small and it isn't touching the back of the trigger so the trigger rod should be fine.

Check on-off by shimming it first using the level 10 shims. If that makes a difference, then grind the small end of the retro on-off pin to make it shorter. If it doesn't make a difference, then your problem is elsewhere, so don't touch the pin.

[MFM-70]

The 0.03" is pretty small and it isn't touching the back of the trigger so the trigger rod should be fine.

Check on-off by shimming it first using the level 10 shims. If that makes a difference, then grind the small end of the retro on-off pin to make it shorter. If it doesn't make a difference, then your problem is elsewhere, so don't touch the pin.

I do not have a lev 10 bolt.
How thick are the lev 10 shims?

[athomas]

The level 10 shims are .01"

[MFM-70]

The level 10 shims are .01"

Ground .010 off the small dia. end of the pin and it seems to rip now. AWESOME!
I will try it to night on the chrony to see if I get ant shootdown that I cannot detect by ear.

I dry fored it about 20 in a row and it seemed good. trigger pull is about 1/2 as promised.

Should I take another .005" or so off the pin to give it a bigger window or leave it be?

Thanks all for the help!!

[MFM-70]

OK I got the marker home and test fired a bunch of shots in a row (20+)
Very consistant velocity but got a leak when i let go of the trigger.
Leak stops when I hold the trigger.

Is this something specific to the RT on off, or should I just consult the Tom Kaye vids and follow that path for the fix?

Thanks.

[fhawkeye]

OK I got the marker home and test fired a bunch of shots in a row (20+)
Very consistant velocity but got a leak when i let go of the trigger.
Leak stops when I hold the trigger.

Is this something specific to the RT on off, or should I just consult the Tom Kaye vids and follow that path for the fix?

Thanks.

When you hold the trigger down you are cutting off air-flow to the front half of the valve. If the leak stops when you hold the trigger this typically points to the seal in the power-tube. I would start by checking and replacing the power-tube o-ring and see if that helps.

edit: this is something universal with all valves so yes, you could consult the Tom Kaye videos to find this information.

[athomas]

Very consistant velocity but got a leak when i let go of the trigger.
Leak stops when I hold the trigger.

This is an indication that the problem is in the powertube. Most likely, your powertube oring needs replacing, or you need a shorter powertube spacer. Try a new oring first.