Have a small Russ Hamm lock bought back in 70's. Son has used it to build .32 cal rifle. Not getting enough spark only going off 50 percent of the time. Hammer doesn't seem to be dropping very fast. Thinks maybe the main spring is to weak? The spring at one time was ground a bit to snug up to barrel my fault not his :: . I am guessing need new main spring . Any ideas or where to go to have spring made would be grateful. Or if anyone would know of a spring that would fit small Russ Hamm lock. Thanks