Originally Posted by Skibbo
This reminds me so much of an old hand cannon. It's pretty awesome. This might not be possible with the set up you have, but would it be possible to leave the remote connected w/the slide check pushed forward? If the reg is set to the pressure you want to achieve in the marker, I would think that it would equal out. Might be wrong though.
When the spool pops back, there is nothing to hold the air in. It's just a can of air held by the spool and the check in the fill fitting. You could leave the remote attached and move the slide check back and forth, which would be the safe thing to do with the muzzle loading bit anyway.
You could push the spool back into place while gas is flowing though, since it is balanced. I was thinking a flow restriction might help the repeatability of the regulator anyway.
A separate fill mechanism is where the matched pair idea came in, using the same setup to fill both markers. I was disappointed in the dueling capability of goblins, so I'm building a hobgoblin.
A note on the fill nipple. There's a little shoulder left in the body to keep the check pin from coming out. It was a bit of a pain to get fit, with multiple tap runs and a few runs of a better cut brass fitting to get the threads to pick up the fat fill nipple threads. Since it was some old fill nipple anyway, I put a buna oring in it to seal at low pressures better.
I'm thinking a piece of brass or steel plate would be easier to dress up for the sear. I wanted to have some room for changing the engagement on it, but it doesn't need much in this arrangement.