I spoke with the man who I purchased this pistol from recently. He said that this pistol ,which he had J.D Jones build for him, will chamber and fire a full length. 375 H&H magnum round although it will not extract the full length case 72.5mm without removing the bolt. The trimmed down 69.5mm length cases will extract properly. J.D. said that he can and would put a relief cut on the receiver to allow for extraction of full length cases if someone so desired. A question arose about the unique chambering of this firearm. This is the answer. Best Regards.