You're supposed to have the reg papers with the gun when you take it to the range, but i'v done it before without and just had the transfer notice. If you get caught you can play the newb card "I thought this transfer notice was the reg?". I'm not recommending doing that, i'm just impatient when it comes to dealing with the CFO.
I knew a guy who did that and the cop said it happened all the time, they both had a laugh and joked about the system a bit then he went on his merry way, no fine, kept his gun. Of course it depends on the cop... I think he lucked out.