Here's the complete rifle. I'm using the built-like-a-tank SWFA fixed mag scope (I've bashed these things around for many years as utility scopes and they just keep going) for testing; without it on top the rifle weighs in at 6.5 lbs. One thing I've learned the hard way is to beware of intermediate length gas systems--different manufacturers have different ideas what length that is so I buy exclusively Wilson's for their barrels.
I'm a bit mystified by the published numbers I'm seeing for the 300 Ham'r--for example loads at Hodgdon's resources throw way out of bounds maximum pressures in quickload. Quickload itself has in it's cartridge database for the Ham'r 32.20 H2O max fill--but I'm not seeing anything near that in my measurements or what I've seen in other published data for case capacity (my max fill comes close to the useable case capacity). Wilson's ammo is reportedly getting 2,400 to 2,500 fps in 125 to 140 gr bullet weights; I haven't the slightest idea how they are getting that with the powder options I've seen.