Doesn't the fact that they're
SOLD through the mail make the answer obvious?
Assuming the pistol is a REPLICA of a pre-1899 gun (i.e., an 1851 or 1860 Colt, 1858 Remington or a LeMat), does not take fixed ammo currently in production, etc., the gun is EXEMPT from the regular Federal prohibitions against interstate transfers. This is why Cabela's Dixie Gunworks, etc. can sell them.
You might have bothered to do the minimal effort of checking the BATFE website before posting your inquiry. It took me all of 30 seconds on GOOGLE to find it.
http://www.atf.treas.gov/firearms/faq/
Do antique firearms come within the purview of the GCA? [Top]
No. "Antique firearms" are defined in the following:
TITLE 18 U.S.C. CHAPTER 44 SECTION 921(a) (16)
(16) The term "antique firearm" means-
(A) any firearm (including any firearm with a matchlock, flintlock, percussion cap, Or similar type of ignition system) manufactured in or before 1898; or
(B)
any replica of any firearm described in subparagraph (A) if such replica- -
(i) is not designed or redesigned for using rimfire or conventional centerfire fixed ammunition, or
(ii) uses rimfire or conventional centerfire fixed ammunition which is no longer manufactured in the United States and which is not readily available in the ordinary channels of commercial trade; or
C) any muzzle loading rifle muzzle loading shotgun, or muzzle loading pistol, which is designed to use black powder, or a black powder substitute, and which cannot use fixed ammunition. For purposes of this subparagraph, the term "antique firearm" shall not include any weapon which incorporates a firearm frame or receiver, any firearm which is converted into a muzzle loading weapon, or any muzzle loading weapon which can be readily converted to fire fixed ammunition by replacing the barrel, bolt, breech-block, or any combination thereof.
27 CFR 478.11
Antique firearm. (a) Any firearm (including any firearm with a matchlock, flintlock, percussion cap, or similar type of ignition system)
manufactured in or before 1898; and (b)
any replica of any firearm described in paragraph (a) of this definition if such replica (1) is not designated or redesignated for using rimfire or conventional centerfire fixed ammunition, or (2) uses rimfire or conventional centerfire fixed ammunition which is no longer manufactured in the United States and which is not readily available in the ordinary channels of commercial trade.