44/40 instant gun blue

[Old Scribe]

I'm having a problem touching up some rust spots on a friend's 24V Savage. I've done bluing work before and wanted to try 44/40 gun blue.
I preppped the rust spots as I always have and applied the bluing. New bluing looks great, problem is the edges of the rebluing is mottled, having different shades of blue.
What's going on and how do I get rid of this?

[drmjf]

I use 44/40. I never have had your problem. Did you leave it on too long? I have found it only takes a couple of minutes. Did you clean after preparing the surface or before?
Hope this helps.

[Old Scribe]

Rodger all your suggestions. After leaving it unoiled over night, it looks much better the next morning. Put some Barricade on and bingo! Thanks for the advice.