Friction O ring

Hi from South Africa!

Had the same problem a few days ago.

I used a BS004 (1.78mm Section x 1.78mm Bore) sized O-ring,

works well on my Wildcat MK3 magazine.

Got it at O-ring suppliers locally, but where to find it in the US

I won't know.

The size should make the search much easier.

Thanks for the help and size I’ll start with the size. And go from there