T/C will be .224 with a 1:12" twist. Should stabilize 50 grain bullets. A 10" barrel may not get enough velocity to stabilize them, but I only know 1 way to find out. Load some up and shoot them. Also, you can shoot the .223 bullets in your barrel, but accuracy will not necessarily be phenominal, again the only way to know is to shoot a few and find out.