brakes pull to left

[beast_3]

My car has started pulling to the left when I first step on the brakes. If I let up and re-apply them, there's no pulling at all, car brakes smoothly and well.
I've got older cast iron spoked drums on the front and cast reproductions on the rear.
Other than the pull to the left, everything works by the book.
Any thoughts?
Bob

 

[J Franklin]

Clean the linings of any debris or oils and inspect for proper operation and lubrication. Readjust brake operation, and retest on the road. That's how I would go about it.