Most folks that like the idea of doing this should realize that once they factor in all the costs they're probably a little in the hole when it's all said and done. If you consider that the cost of of the fun of trading and you can afford it there's not anything illegal as long as you follow the ATF and state rules.
If it gets to be more than just an occasional thing, look into whether your state requires some sort of licensing (matter of fact, make sure of what level of hobby business your state tolerates before getting into it) and or permitting. It may simply be a small fee permit or it may be a real license.
OTOH, if you actually find that you're good enough that you're actually making money above expenses you have to follow the income tax rules as well (Fed and/or state). If you think you're ahead on the money side look at all the expenses you've incurred doing this instead of sitting surfing the net engaging in "fantasy gun trading" and report your actual profits on your taxes (remember that Capone was busted on tax evasion instead of his other "business" activities).
If it gets to be more than just an occasional thing, look into whether your state requires some sort of licensing (matter of fact, make sure of what level of hobby business your state tolerates before getting into it) and or permitting. It may simply be a small fee permit or it may be a real license.
OTOH, if you actually find that you're good enough that you're actually making money above expenses you have to follow the income tax rules as well (Fed and/or state). If you think you're ahead on the money side look at all the expenses you've incurred doing this instead of sitting surfing the net engaging in "fantasy gun trading" and report your actual profits on your taxes (remember that Capone was busted on tax evasion instead of his other "business" activities).