This guy had a similar problem. http://thefiringline.com/forums/showthread.php?t=512304
It is pretty common problem.
It is a good idea to have a copy on you. I carry a full sized copy in my range bag and a pocket sized one in my wallet.
I dont believe it is required any where that you have the paper work on you but it can save you a huge hassle. AFAIK the only people you are required to show it to is ATF agents but I have shown mine a few times.
Shot placement is everything! I would rather take a round of 50BMG to the foot than a 22short to the base of the skull.
all 25 of my guns are 45/70 govt, 357 mag, 22 or 12 ga... I believe in keeping it simple