I would say a big fat NOT on that one , your not 18 , you wont be 18 till your B-Day , so it wouldn't be legal for the DEALER to do that , you would still be a minor 10 days prior .
JMHO there , but it is probably fact too
Slight difference in your 870 and Mini-14 costs , like double for the Mini-14 , hope you knew that
You must be planning to be part of the ZOMBIE APOCALYPSE ASSAULT TEAM
I am surprised you have not called your Gun Shop and asked them about the 10 day thing ?