Geez...there is so much wrong in this thread...
First off Cheytac and Thor are 2 different companies so you couldnt have called and talked to manager of Cheytac/Thor.
Second off Cheytac is financially restructing for the half dozenth time and really not expected to come out of this one.
Third off the Thor 408 is produced by EDM Arms exclusively for Knesek Guns and hence named Thor.
Forth off the 408CT cartridge itself has been surpassed for about 5 years now lol. The 375/408 (commonly known as the 375 Cheytac BUT in reality Cheytac had nothing to do with its conception--its just something else they put their name on..sorta like the M200 being it was designed and built by EDM Arms that Cheytac took for their own).
Fifth..The 375/408 has been surpassed for about 13 months now and that is by cartridge I been working on for about 3 years
There are LOTS of differences between the XM and the Cheytac M200 produced by Becker or the original batch produced by EDM Arms....ALL DIFFERENT ever so slightly..biggest difference that cannot be seen is the barrels. All barrels for either 408 or 375 or any cartridge shooting solid projectiles are not the same. It actually depends on what projectile you intend to shoot and make sure the barrel you have can obtain best results from that projectile.
Thanks
Plinky.......is that you?