Vlad, I go over 2 or 3 times a year for the past 20 years with live ammo both ways. Have never had a serious problem. Once the German airport police at 0600hrs on a Sunday morning demanded that I have a US permit to own the ammo that I was taking home, and did not think my US import permit was enough. They couldn’t comprehend that there were no ammunition ownership permits in the US. I go on the internet and get a 24 hour police phone number for the European locations where I fly in and out. I also keep the phone numbers of the show organizers since they have close relations with the police to organize the meeting. Eventually I told the police to call a senior inspector or I would call one, and they decided that it wasn’t worth the trouble and I got on the plane.
My other issue was 10 years ago in Holland when I arrived about a week earlier than everyone else on my way to the Czech meeting before the ECRA meeting. The Dutch permit is a special one for the ECRA and the Dutch Customs officer didn’t recognize it. Took about 2 hours for him to contact the right person who told him that they had not send down the instructions and notice on the ECRA permit because they didn’t expect anyone to use one for about 4 more days.
For over a hundred trips, that is pretty good.
Some simple rules.
Pack your ammo in plastic ammo boxes or other partitioned boxes designed for ammo so it is not loose. This applies to both inert/fired items and live ammo since some inspectors cannot tell the difference between live ammo and dummies (particularly true when leaving the US). And, tape a label on each box of inert/fired rounds clearly stating that it the items are inert and do not contain powder and that the primer is inert. Live ammo should also be labelled as such. I always put a copy of all my permits in the bag with the ammo, inert or live.
Get a letter or something written from your local Sheriff or Chief of Police stating that you do not require a permit to own ammunition. I have gotten a concealed carry permit which works well. About every second or third visit I am asked for my authorization to carry ammunition. On my ATF Form 6, in block 10, I clearly state that the ammo I am importing is for my personal use and explain that I am a collector and ammunition researcher and write articles and books. That satisfies the ATF, TSA and other European authorities.
Never violate the weight restrictions of 5Kg per person.
Always declare your live ammo when you go through customs. In the US, Customs has told me that with an approved form 6 for import (not a form 6 (nia) for non citizens) there is no requirement to declare the ammo, but I tell them anyway.
Keep some phone numbers as I mentioned above just in case something gets messed up. I have never had to actually use mine.
Check the rules in the countries you pass through. Fired cartridge cases are probably OK, Dummy rounds are generally OK, but if they have tracer or AP or other fancy bullets they could be a problem in some countries.
All the European countries require permits for live ammo, even if you are just passing through. If you fly to the UK and take the ferry to Holland and then drive to the meeting in Germany, you will require permit from all three countries. In most cases the consulate in the US can issue a transportation permit, but I have avoided that by flying form the US directly to the country with the meeting.
I have never tried to mail or UPS/DHL ammo back to the US, primarily because of US rules and US Customs which seems to have different rules at different locations. Ammo in most places in Europe is defined as having a case, primer, powder and bullet or equivalents to be ammo. Otherwise it is not generally regulated with some exceptions. The ATF does not make the same distinction. The last time I checked their material could be interpreted that ammo includes the separate components, fired or not. I have been told unofficially that this is intentional and that convicted felons have been arrested for having a fired cartridge case. Flying with ammo is so easy that I don’t try to ship.
Hope you get over to Germany for the meeting.