I receintly aquired a 20+ yr old a 1? of a kind super 14 tc. The problem is the man who was developing the ctg died shortly after getting the gun, so he did not get to do any serious load development. Fireform loads only. The case is a 307 shortened .257, and necked to 7mm. More details are listed in my thread in wildcat cartridges. If anyone has any info it would be helpful. TIA