I am looking at buying a used GS that is inletted for a T3. The fella also has it inletted for the Atlasworx BM in a LA....he was using it on a 6.5x55 Swede. So my question is, is the inletting the same for the BM from McM regardless of the caliber? Can I simply swap the bottom metal to a SA and run a .243 out of this?