neck resizing

[psteinmayer]

Neck sizing .303 is not a problem as the .303 headspaces on the rim, same as the 30-40 or any other rimed cartridge. Please remember that 30-06 headspaces on the neck taper. If you only neck size, you will not reform the taper, which is crucial for the cartridge to seal in the chamber. Lose that seal, and you could experience leakage of dangerous hot gases past the bolt! 30-06 should always be full-length sized and trimmed... each and every loading. To ensure your cases have longevity, you should anneal the neck and taper. Most military 30-06 (ball) cases will be annealed already, and should be annealed every so often to keep them in good condition. Civilian 30-06 cases may, or may not be annealed. Look for discoloration of the neck and taper - to around 1/4 inch below the taper.

[13Echo]

For my bolt and single shot rifles I prefer neck sizing. However I do have to keep the cases separate for the individual rifles as the cases won't interchange for the same cartridge. The chamber in the Mod 70 7x57 is larger than in my custom Mauser 7x57. Case life is better with neck sizing, especially with the Lee collet sizers. For the Garand it's full length resize. The less the brass is worked in sizing and in expanding to fit the chamber when firing the longer it will last and the better the potential accuracy.

Jerry Liles

[joem]

I don't get neck splits on .303 but case head seperations. I have two .303 rifles. I retired the 1942 English made one to a wall hanger because the brass streached tooo much. The one made in India in 1966 seems to be better with case life.