Got a question...

I'm just about finished with my build (I know man-law states I must post pics...coming soon). Sporting a McGowan 7mm Rem Mag bull contour on 111 action. My bro is going to reload some for me but he's in another state. Critical info he needs is the OAL of where to start on the reloads. I plan on trying the 175gr Accubond LR. Unfortunately he doesn't have access to my rifle as I have it with me. Anyway I can accurately come up with a good OAL for him to start reloading for me? I don't have access to a reloading press where I'm at to fit a test round to the lands. Thought maybe someone would have the same barrel and could share their info or someone in the know could tell me a way to measure. Thanks.