here is a mod on how to make a double springed night finder with better o-rings.
a 4-6kg load spring or one out of a buzz bee twin tek
Vaseline or other lubricant(wd-40 etc.)
Step 1: SPRINGS
now go ahead an take apart the gun.
you will need a screw that is the same length a the night finders, but preferably with less width. i used the one out of a buzz bee twin tek (you buy it in a two pack) i did this because it was broken.
place the BB spring (or whatever spring you have inside the NF and place to the side
Step 2: O-Rings
Now to replace the o-rings
just follow the pictures.
you dont have to put 3 o-rings on it just worked well for me.
now lubricate the barrel
Step 3: Re-assemble
now go ahead and re assemble. this mod should have at least doubled your range. it now shoots between 50-70ft(16-20meters flat. possibly more.