Remington No 1 Creedmoor

[Caprock]

If you're trying to buy a Creedmoor then you need Marcots book on Sporting Rifles as a reference guide. Caliber markings vary but in general a 44 denotes 44-77. Sometimes a 44 S denotes 44-77 but designed to shoot the special 90 grain load in the same case or it could be the 44-90 2 7/16 BN. If someone tells you 44S stands for 44 Straight then he likely doesn't know what the hell he is talking about. The 44-100 straight and bottleneck versions can be marked in a variety of ways and sometimes the same way. This is all in the section on Number One Sporting calibers that has a table of stampings.

The bottom line here is that unless you do a chamber cast the caliber is anyones guess unless you buy from someone who is very knowledgable about the rifle he owns.. Remington caliber markings weren't exact plus people changed barrels and had reamers back then you know.