I asked in another post about a leaking shining career iii 300 in 22 cal. I got the nerve to take it apart and found the destroyed o-ring where the pressure gauge is. Now to the bigger problem. I don't know the exact size and the hardware stores don't have one even close. I was thinking of ordering a o-ring assortment kit. But they want to know if its metric or not. I have no idea. Any suggestions would be truly appreciated. It is a small o-ring.
