Tac One issue

[chappy350]

[Billz804]

Do you know whether your tank is outputting 850psi?

[chappy350]

[chappy350]

[Sandman]

If the gun is not gassing up and trigger is not coming forward.

You have no air or air supply not reaching gun properly.
Gun is not turned up enough to get the valve working - happens more often than you think....people don't realize how far to turn velocity adjuster in after a rebuild.
You have assembled part of the gun incorrectly.
trigger rod is not properly in the frame - rod sometimes gets misaligned when you put rail and frame together.
On/off assembly is not assembled or installed properly missing parts or orings.
Basically something is not rebuilt and installed properly.

If the trigger feels pressure but you can't shoot, it may be in your powertube. Too tight of a carrier. Too heavy of a spring. Improper trigger rod length.
Bent shim.

That's a small laundry list to help diagnose....

Sandman

[chappy350]

Adjusting the regulator seems to have fixed the trigger issue, it now gets stiff and seems like it wants to fire, but pulling the trigger does nothing

[athomas]

Have you turned up the velocity to a higher value? If it won't fire, even at the highest setting, then you haven't got enough pressure to overcome the force holding the bolt back. That is usually caused by bolt stick. Have you tuned the level 10? You will need the proper tension bolt stem by the carrier oring. If its too tight, it won't release the bolt. You want it adjusted so that it is using the largest carrier size that does not leak. Don't use any shims.

[luke]

(I'm assuming you're running an RT on/off, if not this may not pertain to you)

My guess is you haven't broke in your on/off yet. In the last year I've found 7 or 8 markers with either new on/offs (or freshly rebuilt) with this exact problem. All of these seemed to have excessively tight o-rings that squeezed the on/off pin so tight it prevented that initial 'pin set' you need when airing up your marker.

On the new on/offs I've been doing a quick polish on the large end of the on/off pin with a wire wheel on a bench grinder. I've noticed the new pins coming from AGD have a discolored tip, it looks like some type of surface treatment (I have no idea what it is, just a guess) so I've been doing a quick polish on them when I encounter them. I think it may be adding a little drag on the initial break in. I also believe the new o-rings may be just a smidgen tighter. All just a guess based on the issues I've seen recently.

Along with polishing the pins, I also pull the on/off and heavily oil the o-ring in the bottom of the bore.
Then increase the velocity pressure as high as you can without venting out the back.
Once the pin sets on gassing up, cycle the marker 50 to 100 times, then chrono the marker.
Another trick is to install an Emag on/off pin (0.712" long) break in the o-rings then reinstall the pin you intend to use.
One other issue you may or may not in counter, is excessively long on/off pins that will cause the same type of problem, if the pin is too long it wont set properly when the marker is aired up.
I run .740" pins in every build I do (Not Emags) and have never ran into a marker that didn't operate properly with them. In fact I grind all the pins to this length when I build or repair customer markers.
That said I have found 2 or 3 markers that would only run with pins around .725" or shorter.
Dont forget that a trigger rod that is adjusted to long will cause similar problems.

Over all, none of this is a big issue if you know up front how to deal with it.

[chappy350]

[luke]

Just start with oiling the piss out of that o-ring and turn up the velocity, see if you can get the on/off to set properly.

[chappy350]