So, I think I understand it now: Call them 99A and 99B, both starting in 1920/21ish, with 26" barrels. Then, in 1926/27 both changed from 26" to 24" barrels (and that 99A 24" barrel that Murrayy talks about would be the same 24" rifle).

Last edited by KeithNyst; 06/28/16.