chambers in Shilen .223 barrels

[max]

I notice that Shilen offers three diffferent chambers for the .223 Remington: .223, .223(.246), and .223(.252). Are they referring to the different throat lengths and if so, what is the standard length? Are all of these available in Savage prefits?

[kslefty]

Actually it is different neck diameters, the tighter ones are for precision shooters but will require neck turning your brass.

[helotaxi]

The tight chambers require neck turning but can really help with brass life and keep everything in-line.