Well, I got the Rolling Block custom brush gun and I have fired it some. I've used 23.0grs Re7 and 25.0grs 3031, both under 517gr Lyman 457125 bullets cast at 9.5bnh and 22.0bnh, and with oals of 2.55 and 2.880. The gun is on cruise
control with these loads, they are well below trapdoor levels.
The gun is definitely a Remington 1902 No. 1 action. It appears in great shape. the block is very tight, as is the hammer. The main spring is VERY robust, and the trigger return spring is ridiculously strong and makes the trigger pull unbearable. I am going to have to replace it before doing much more shooting.
My hope is that the gun easily handle loads in the 35.0grs of 3031, or 32.0grs of Re7 range. It will be used with cartridges loaded to 2.880 oal using the 517gr bullets.
Is anyone else playing with one of these guns? I would love to compare notes.