[Brian Pfleuger]

Peak pressure has a big influence on barrel life. Look for loads that produce less that 59,000psi. The SAAMI max psi for 243 is 60191, so you're going to be near max on those loads anyway. Typically, the last several thousand PSI is a lot of pressure and not much velocity.

For example, using default settings, QuickLoad predicts that Reloader-17 can produce 3610fps from a 65gr V-Max in a 24" barrel and the pressure is 58500psi. If you go to max SAAMI pressure of 60191, you gain only 30fps. Step it back to just 57,000psi and you lose just 27fps.

So, you're getting just 7/10th of one percent more speed for a 5.5% increase in pressure.