Why wont this Muzzle Brake fit this Rifle?

[Gberberian]

On a 1945 Russian Izhevsk M44 Mosin Carbine, Why wont this muzzle break from this website fit on the muzzel.

http://combatoptical.com/catalog/MOSIN-NAGAT-M44-MUZZLE-BRAKE-145.html

NOTE: I have checked other websites also, It looks ultimately the same but it does not include the "Anti-Russian" part.