Wires and Walls.

[GoldGolfBallGun]

Hello Fellas, GGBG here.
I have done my own research to no avail and was curious how others (if at all possible, neatly and safely) feed wire through a curved surface (chamber) and have it sealed. I know there are cable grommets but they aren't curved and to my guessing they won't seal unless screwed to a flat surface.
Also my chambers are steel.

[Moonbogg]

I've drilled holes and fed wire through an aluminum chamber and used epoxy to seal it. It's been 12 years and it still works. Another more recent cannon I made uses a spark plug. Drill and tap a hole and stick a spark plug in there. Well, the spark plug went through an end plate, not the chamber. But a spark plug might still work depending on the thickness.

[GoldGolfBallGun]

Thank you for the suggestion, I'll definitely go with the metal epoxy.
And I will be upgrading the cannon over time but for now it'll just be a base model that operates and build onto that. Spark plugs will come in due coarse.
I did not occur to me I could tap into a cylindrical wall.