I use a dark gray for dark plugs for the only reason to keep a white primer showing on a black plug after it gets cut up. I have been using a darker color primer for dark painted plugs. White for lighter paint plug. What does everyone else do for primer colors?

white, never really gave it much thought

Mines all white.
Some yellow paints won't cover dark primers.
I once put a gallon of yellow paint on an MBTA truck and couldn't cover a 3 inch stripe!

gray Rusto, about 1/2 full, white BIN, ooo-almost empty,....

Gray it is!

I use whatever my hand lands on first.:)

Besides Billy, beat up plugs with contrasting colors always catch best!:uhuh:

White... if they make it to bare wood, I consider the plug a sucess...

The color wont matter,,,, Like Jon said the more beat up the plug the better it seams to catch,,,,,

My primer colors have varied over the years,white, grey, black,,,, None of the colors seem to make a difference.

I did find the coverage of grain is better w/ gray. 2 coats of white does the trick. 1 coat of gray. I did the gray for the dark color plugs. This dipping method is a piece of cake. Set up a drip box and 50 plugs done < an hour.