Well, I wasn't military in Afghanistan - I was a civilian contractor with base privileges. But my point is that if it's made before 1898, you don't need anything. I couldn't bring those Martini Henry's back in the plane because it was a military contracted plane. However, theoretically, on a civilian flight, I could just check it and customs wouldn't have anything to say about it. I did this once with a gun I bought in Quetta, Pakistan. And I discussed this once with an ATF guy in Martinsburg itself via Tie line with the requirement for ATF paperwork for center-fire weapons first was instituted.
So out of Afghanistan, in lieu of carrying them back, I mailed them from the APO.. The drill was 1) take the gun to the Provost Marshall with ATF clearance (after 2011). Show him/her the gun - they made out paperwork in 4 copies. 2) take the gun and paperwork to the APO - show it to the post master and then wrap it at the APO so they see that say an RPG or MG-42 isn't being substituted for the gun on the paperwork; They'd then stamp every crevice where the tape was with dozens of stamps. A few weeks later it arrived at the house...dozens of those guns were sent back with no limit.
As I said the re-enactor crowd really got into the Pashtun Enfields and as a result the price in Kabul for a muzzle loader went up from about $95 to near $500 in one year. I've seen at least one Pashtun muzzle loading Enfield in a Civil War antique shop in Fredericksburg with Confederate stamps on it but a sub-continent serial number being advertised as an authentic Confederate Enfield.
Now I last mailed guns back in 2012. But my feeling is the process is still the same. If you buy a pre-1898 gun abroad and can get it out of Europe...you can check it as luggage and bring it back yourself. Call ATF...I may still have a name and number and talk to the guy, I still have copies of the paperwork and can post it if anyone thinks it helpful.
1) Generic ATF Form with approval (ATF approval for pre 1898 centerfire weapons required after 2011 in Afghanistan).
Along with photos including SN's of the gun(s):
3) This was the form issued by the Provost Marshall to send it back via APO. Again, this is needed only for the APO:
