Mine is also a #1. 1B.
It is a shooter..... Never shoots over 1.5"
Will shoot 3/4" with WBY factory 150SP or 130AB.

I am thinking it took almost 74grs of R22 in it and a 700 I built to get to 3400 but can't remember for sure.

Dave

But as for me and my house we will serve the Lord. Joshua 24:15
I can do all things through Christ who strengthens me. Phil. 4:13

I DON'T NEED A WSM AS I HAVE A WEATHERBY!