Being the same age as you, I understand your worry. I paid for my firearms through my parents this year. That could be a problem for you, however, if your parents are not the pro-firearm type.
Your best bet is to convince them of the reasoning behind owning a firearm rather than trying to get them to allow you a firearm outright. Explain why owning a firearm or two is a good idea. Explain that bad guys will always be able to get firearms, that firearms are no more the problem of killing than pencils are the problem of misspelled words and it is within you and your parents rights to defend themselves against violent assault, something that will become difficult to impossible if you do not have firearms of your own. Don't just repeat what I said! Do some extensive research! Create a reasonable argument and try to present it carefully and little by little. Honestly, this is the only choice you have at this point being underage. Research and a mature foolproof argument(s) is the key. Christmas present is a good idea.
Its entirely up to you, but you might be better off starting with something more um... how can I say it... politically correct. Something like an SKS or another semi-auto rifle that is less stereotyped than an evil black rifle might be a better place for you to start out. Again, entirely up to you. Sometimes looks can kill.
Good luck!
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