MuddinPede_98C

Does anyone know how big the o-ring is on the rear bolt? I was wondering if anything would fit it, like a tank o-ring or a barrel o-ring or something?

Thanks

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Corey Nichols

Orange to Black Alias Timmy | Infamous Board | Dye Ultralight | CP Roller Trigger | Black Unimount | Halo B | Pure Energy 68/4500