I haven't received a reply back from them for a challenge I sent last February. I sent it to:
NICS Program Office
Post Office Box 4278
Clarksburg, WV 26302-4278
However, I sent it without a NICS Transaction Number (NTN), and according to two different people I later talked to with the BATF on the phone, they simply refuse to handle appeals without that number. Did you include that #? Because they don't deny me, there isn't a number issued, so I can't include it. However, I don't get an approval. So if the dealer I'm buying from isn't paranoid, then I get the firearm after a three day delay. If they are paranoid, I'm denied the purchase because of the dealers fear of the BATF. Either way, it means I can't buy a firearm at a gun show.
According to one stat I read on the BATF's web site, less than 1% of the denials they issue are successfully challenged. So, you can either take that to mean that 99% of the denials are because the person can't legally buy a firearm. Or, the BATF is illegally denying many of the 99% from buying a firearm, and they are not processing the appeals or the buyers are bothering to challenge it.z