I think all the G2 XM-24 have the new blade stop. There were 10 G1's.
No, Gen 2 XM-24 has the traditional blade stop unlike the Gen 4 XM-18 3.5" which has the new blade stop location.
Mike is right, this is covered frequently, it isn't that hard to figure out.
- Gen 1 and Gen 2 of XM-18 in 3"
- Gen 1 through Gen 4 of XM in 3.5"
- Gen 1 and Gen 2 of XM-24 (as noted, there were only ten of the Gen 1 XM-24 in all Ti with the Maltese Cross).