I built my 23" 35 Whelen AI back in the early 90's and copied G. Sitton's loads also (AA2520), just like Jim. I was chasing 2600+ with 250's and ended up blowing the only primer I have ever done in 40 years of handloading pursuing that goal. I have no doubt I was flirting with the kind of pressures Jim referenced above. Nowadays, with the new powders, I can shoot the 250 NPT at 2650'/sec with very mild pressure (Speer's max is 2700', but I quit over a grain below their max.) Can load those cases many many times. We've had great progress with powders for the Whelen. For some reason, their is a contingent of folks who seem really bothered that the Whelen is now capable of 150'/sec or more than it used to be. They imply that's not the performance its creators "intended." I never met Messrs. Howe or Whelen, but I'd bet a box of 250 Partitions they'd have been thrilled with an extra 150'/sec in their baby. Now I'm just rambling...
