Technically not a poll tax, but I think your line of reasoning is correct, taxing a federally protected right (like voting--the true poll tax) is dangerous territory. Of course the counter argument will be "you can still have your muskets"
Also to think about--since they want to shove it through via reconciliation, it could be repealed via reconciliation. Remember the (D)s exercised the "Nuclear" Option and then Yertle the Turtle nuked them back for 3 Supreme Court Justices? Always be careful of your ideas, lest they be used against you. Let's nuke your tax rate to a Flat Tax at 15% bitches. Oh an remove all import taxes on guns an ammo.
In a bit of irony--Dissension in the colonies was started.
Over taxes....