Those are pics of the proofs on the gun that the thread is about. I was going to buy the gun and had Cabelas put it on hold for me until they could send me some pics. 400 Nitro helped me a great deal with what to look for. The gun is in fact marked for Nitro. The information on this thread as well as no proof marks in relationship to the gun being for jacketed bullets as well as the super light weight tell me it is almost certainly a nitro for black powder gun, which I don't want.