Grand Regulation

[Dpshans@AOL.COM]

List,

Here's a fairly basic question from a somewhat newbie: I've noticed on a few 
grands (new and used, various makes) that a few hammers do a lot of 
double-striking on a soft blow.  Seems this is a situation of perhaps too 
strong a repetition spring, or perhaps improper checking, but I've not read a 
proper diagnosis or regulation sequence in any of the literature.  Please 
help further my knowledge of "Regulation 101," and thanks in advance.

Dan Dannenfelser
Sacramento, CA