It's on top of the city flag closest to the German main base. Its on Eastern Blitz, not Counterattack. There is also a HE111/LOs bomber kit inside, at the very end of teh longest tunnel.
There's also one in Road to Ramelle, in the rail yards' SE corner. I don't think there's anything in there, though.
Man,I looked at the shotgun in the bunkers at that flag near the beach,but,no shotgun. Is it still on 0.67a?Or is at another place?
Yes, today when I looked for it I couldn't find it. I don't think it spawns unless the Americans hold the flag.