You do not have to list caliber on the 4473 form. Where it reads TYPE of FIREARM PURCHASED you only have to write handgun or long Gun.
When I had my C&R FFL the only other form I had to fill out NOT for my purchase but for a sale was a state form. Again I only wrote in handgun or long gun.
The SS # is for several reasons but you never give it when you do the NICS telephone check. The resons are:
> Accounting. The SS # of the guns coming in match the guns going out. Used when the BATF&E comes to audit
you
> Trace a gun from manufacture to FFL to owner in a murder type of thing.
The Form 4473 only has to be kept for twenty years. It only needs to be kept on the premises of the FFL business for seven years. After that it can be kept at a secure location.
I know several FFL businesses who keep their 7+ year Form 4473 in a wood shed a safe distance away from their business but close enough to throw a match into.
Stuff happens man.
Now with all that written there is a movement by the BATF&E to have all Form 4473's scanned and sent to them for book keeping purposes. This is not law at the moment however I have heard of some FFL folks doing this already.