Poll:
Who is getting 3240 fps out of their 24" gun with 65 gr of IMR4831 and a 150 Nosler Accubond or Partiton? Historically Nosler velocities are higher than any other source.
Again, who is getting the Nosler published velocity of 3240 fps with one of the 150 gr Nosler bullets using a 65.0 gr powder charge of IMR4831 and 24" barrel length? Doesn't count if the charge weight is higher. Let's stick with published data.
When you run more than published charge weight, and get more than published velocity, it's not a close held secret the load has higher pressure all else equal. To each his own but it's folly to think the rules of pressure don't apply.
Hodgdon shows 65.0 as max for IMR4831 and the 150 TTSX, at 3075 fps. They are using the 150 TTSX, the same 65.0 gr charge weight as Nosler shows for their bullets, but getting 165 fps less.
Hodgdon also shows a max of 62.5 gr IMR4831 with the 150 gr Partition for 2925 fps vs 3240 fps from Nosler data for the same bullet using 65.0 gr IMR4831. 315 fps difference from 2.5 gr variance in charge weight with the same bullet.
The reason for load data difference between manufacturers could be any single one or any number of these... Different bullets, different cases, different lots of powder, slightly different OAL, different chambers, different barrels even if they are the same length, different primers, probably some other things called "variables" I didn't think of.
