Post deleted by Caprivi

Very nice rifle Rick.
I have had 2 Apex's as well as a .244, along with being associated with another Apex. All of them said "Holland's" on the chamber as yours does. That said a 300 and a 375 of former ownership where marked the same way.
See the picture in Igorrocks post.

As to the .242 bore, I would assume you mean groove size, as alluding to the thought of a .243" barrel. My .244 had a for real .245" groove diameter, but both Apex's plus 1 other where all .242"ish to .243". Another .244 I know of (built 4 days and 2 serial numbers from mine has a .244" groove diameter. One would assume that in 1959, exacting tolerances of the rifled tube where a bit of a variable.

All said and wrapped up, all of these rifle shot wonderfully with the Nosler Partition bullet as well as the "softer" standard cup/core bullets as produced by Sierra, ICI, Hornady and the like.
As an aside I have used 50grs H4831sc (your AR2213sc) with the 95/100gr Nosler for 3000fps