Ric,
I suppose it all depends on what the max range a person intends to take a shot at as to what round would be the best.
That said, the 156 gr ULD RBBT will exceed or match any commerical bullet on the market as far as ballistics is concerned, drop and winddrift. Compared to the 300 gr Sierra Mk in 338, it produces nearly identical drop values over 800 yards when driven to the same velocity.
The only reason I know this is because I have tested this bullet in my 257 Allen Mag at 3100 fps head to head with the 300 gr SMK in 338 out of my 338 Kahn loaded to nearly the same velocity(3075 fps).
Drop and drift testing were so nearly identical that the data did not produce a winner ballistically.
That said, this is a fireforming level load in the 257 AM. In the 338 Kahn, this is a full tilt load.
When the throttle is put down a bit we can drive the same BC bullet to 350 to 400 fps more velocity then the Kahn.
It was for this reason that I felt the 257 AM was the only chambering for my Ultimate pronghorn project rifle.
I have been breaking the barrel in today as I do other projects in the shop. It amazes me how the rifle simply quivers as it is fired, NO recoil at all!! I really like those Hollands on light barreled rifles, especially with a big case.
As far as throat and bore life, I admit they will be limited to some degree in this chambering, no way around that. STill this is a big game rifle, designed solely for this purpose and in this role, it will offer plenty of accurate barrel and throat life for most hunters to use if for well over ten seasons.
SO for their design application, I feel throat life is a non issue in a dedicated big game rifle, simply because they will not be used for high volume shooting.
Anyway, look forward to your two project rifles and seeing what they are!!!
Good Shooting!!
Kirby Allen
