If you heat the barrel up with a torch, then apply the browning solution you get a match almost instantly. cool the barrel and wash off the residue( whitish-yellow ) Then oil the gun barrel and let it sit over night. Sometimes you have to clean off the barrel of all grease and oil again, and redo the browning, but usually one time gets it done.
If you use any of these solutions at room temperature, it will take many applications to fill in the scratch or nick in the finish. Be patient.