You shouldn’t be charged any tax by your FFL as he didn’t sell you anything. Likely the out of state business you purchased from isn’t going to tax you either.
But, the state of Colorado does ask that you report all of your untaxed online purchases when you file your taxes so that you can pay the taxes then.
Clear as mud?
What Ray said.
Since 1937, CO law requires all residents to pay "use tax" on any goods purchased on which CO sales tax was not already paid. There is a special form (DR0252) for it and everything.
"The only real difference between the men and the boys, is the number and size, and cost of their toys."
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