I already had a Gen 1 (SPA Varmint) version of this gun but the recent price was too good to pass up so I bought one along with the regulator and tube cap/pressure gauge. A bit of information on the gun and installation-
The trigger adjustment screws weren't appropriate for the application. The first stage screw was just barely long enough but the second stage screw was too short to adjust trigger correctly. I got some long allen head set screws that fit and shaped/polished them for the purpose. As changed, the trigger is really excellent-nice short first stage and crisp break on second stage with the adjustment heads just below trigger surface. Probably an hour spent fitting the screws and it still could use some dampening material to prevent screw walking but the trigger feels great. I will use polymorph plastic to fill the area around the threads for dampening and there is room in the trigger body for that. The Gen 1 trigger was worked and it is a very good single stage trigger now but the two stage trigger makes the rifle better IMO. Not necessary, just an individual preference.
Installation of the regulator was a bit of a problem. I lubed the o-ring, body of the regulator, and threads in the air cylinder adequately but the threads still shredded the o-ring. I had to remove it and it took quite a while to clean all the o-ring bits out of the air cylinder and threads using a shotgun mop and compressed air. Thankfully they do supply a spare o-ring. Heavy hand tight was not enough on the cylinder end cap gauge as it had a slow leak at that o-ring. I used some cushioned jaw pliers to tighten and that fixed the leak. It has been pressurized for 4 days now with no air loss. The end cap/gauge setup shows cylinder pressure and the stock pressure gauge then reads regulated pressure.
Someone else posted this idea but I can't remember who it was-the installation rod can be ground down on the unthreaded end and shaped to use as a long screwdriver to be able to adjust the regulator without removing it from the tube. Excellent idea from whomever first noted that and it works very well.
It has been too cold to shoot here so no test of accuracy but if it is anything like the Gen 1 I already had then that should be no problem. I've been very happy with the Gen 1 for all mechanical function and it has been very accurate. I wish I had owned something like this as a young man when I hunted. It would make a fine squirrel gun-light, easy to carry, plenty of power, and accurate (at least the Gen 1 has been and I bet this one will be also).
The trigger adjustment screws weren't appropriate for the application. The first stage screw was just barely long enough but the second stage screw was too short to adjust trigger correctly. I got some long allen head set screws that fit and shaped/polished them for the purpose. As changed, the trigger is really excellent-nice short first stage and crisp break on second stage with the adjustment heads just below trigger surface. Probably an hour spent fitting the screws and it still could use some dampening material to prevent screw walking but the trigger feels great. I will use polymorph plastic to fill the area around the threads for dampening and there is room in the trigger body for that. The Gen 1 trigger was worked and it is a very good single stage trigger now but the two stage trigger makes the rifle better IMO. Not necessary, just an individual preference.
Installation of the regulator was a bit of a problem. I lubed the o-ring, body of the regulator, and threads in the air cylinder adequately but the threads still shredded the o-ring. I had to remove it and it took quite a while to clean all the o-ring bits out of the air cylinder and threads using a shotgun mop and compressed air. Thankfully they do supply a spare o-ring. Heavy hand tight was not enough on the cylinder end cap gauge as it had a slow leak at that o-ring. I used some cushioned jaw pliers to tighten and that fixed the leak. It has been pressurized for 4 days now with no air loss. The end cap/gauge setup shows cylinder pressure and the stock pressure gauge then reads regulated pressure.
Someone else posted this idea but I can't remember who it was-the installation rod can be ground down on the unthreaded end and shaped to use as a long screwdriver to be able to adjust the regulator without removing it from the tube. Excellent idea from whomever first noted that and it works very well.
It has been too cold to shoot here so no test of accuracy but if it is anything like the Gen 1 I already had then that should be no problem. I've been very happy with the Gen 1 for all mechanical function and it has been very accurate. I wish I had owned something like this as a young man when I hunted. It would make a fine squirrel gun-light, easy to carry, plenty of power, and accurate (at least the Gen 1 has been and I bet this one will be also).