bb weight and hop up adjustment
 

I have a Socom Gemtech Oasis pistol for indoor target practice.

After sighting in for 20 feet,I have some questions:
1.I am using .25 BB Bastards , getting 2 inch groups- good weight for distance?
2. I understand that for this distance, little or no hop up is best-I have inserted a few allen keys into the top opening but hard to know if I am using correct size
and if I am making any change. Clockwise to increase and counter clockwise to reduce. No info in manual and I don't want to have this adjustment head come out entirely- any suggestions?
3. Is it ok to leave propane/green gas in magazine until next session?
Thank You!

My pistol is with shelledpants getting a pimped out kydex holster made so here we go from memory.

1. For that pistol, you could go heavier as the fps can make .25's a bit erratic. BUT, if you're happy with 2" at 20', why change it?

2. Correct. At that range hopup doesn't have a chance to kick in. If you break the pistol down and remove the inner barrel and hopup assembly, you can view the hopup nub as you turn the grub screw

3. Yes. Keep it full.