Just read this write up below found on Shooting Time Mgazine website. Unless I am reading this wrong it says you should not use new Nosler 280AI brass or rounds in an older 280AI rifle. Are there now two different chamber reamers for this round?
Be aware...! Headspace differs between the new SAAMI spec .280 Ackley Improved and that of all the .280 Ackleys built in the custom shops over the years. When SAAMI specs were set up, they changed headspacing from the junction point of the cartridge neck and shoulder to that of a point on the shoulder where the shoulder diameter measures .375", the common method used on many SAAMI spec cartridges. Now the SAAMI spec brass is too short for safe use in older, custom .280 Ackley chambers.
Now we have two .280 Ackley chamber reamers, one the original Ackley version, the other is the SAAMI spec version. Customers should be careful not to interchange the two. If factory .280 Ackley brass is used in other .280 Ackley chambers, case separation near the head may occur. Therefore, if you load for any .280 Ackley, you should always start with new standard .280 Remington brass and fireform it into the proper dimension for the chamber you are working with
Be aware...! Headspace differs between the new SAAMI spec .280 Ackley Improved and that of all the .280 Ackleys built in the custom shops over the years. When SAAMI specs were set up, they changed headspacing from the junction point of the cartridge neck and shoulder to that of a point on the shoulder where the shoulder diameter measures .375", the common method used on many SAAMI spec cartridges. Now the SAAMI spec brass is too short for safe use in older, custom .280 Ackley chambers.
Now we have two .280 Ackley chamber reamers, one the original Ackley version, the other is the SAAMI spec version. Customers should be careful not to interchange the two. If factory .280 Ackley brass is used in other .280 Ackley chambers, case separation near the head may occur. Therefore, if you load for any .280 Ackley, you should always start with new standard .280 Remington brass and fireform it into the proper dimension for the chamber you are working with
