I have finally spent sometime at the range and was able to compile some data. I have preliminary results for 2 powder/bullet combos. The first being the 300 otm with N570. All data was based on a 63 to 65k psi as max. I could certainly load it much harder with the stiffness of the Mark V action, but there was really not need to. Jerry and I are after barrel and brass life, hence the max pressures.
At the range, shooting a 100 yards the 300 otm shined. With a 102 grains of N570 the velocity was very close to 3100 fps with no pressure signs and a .25 cc group. As I stretched her to 200, the target looked like a shotgun hit it. I checked the usual suspects, action screws, bedding, loose scope. None of the above. Baffled I called Jerry and we thought maybe, just maybe the Texan doesn't like the 300 otm. Hoping that wasn't the reality, I loaded up some 280 Barnes LRX bullets and I put a clover together at 200 with the same 102 grains of N570. At the same time I loaded 3 test loads of Reloader 33. They were 104.5, 105.5, and 106.5 respectively. 104.5 and 105.5 were underachievers with a velocity of mid 2900's and 106.5 being the most accurate of them all with the 280 LRX with a top velocity of 3000ish. 106 is very compressed. All charges are loaded with a drop tube.
I really think the 300 SMK will be a hero for the Texan. The SD's with the N570 are under 5. I have a feeling that the magical potion for the Texan will be the SMK and N570. The Texan seems to burn all of the powder you can jam into the case. It loves velocity and shows very little signs of pressure. I look forward to heading to the range this week with the 300 SMK and see how it stacks up. I have no doubt it will show velocities very close to 3100 with a psi of 65 to 66k.......and no pressure signs.