223 cases developing a slight shoulder bulge
Quote from Agent376 on May 10, 2025, 9:59 pmI started loading 223 for my AR on the 550C. I am getting an occasional case with a mild bulge at the case shoulder. I have adjusted the sizing die up and down; powder die up and down; seating die up ( so it does not crimp the bullet) and have a Lee Factory Crimp die in station 4. I am using a Dillon Carbide sizing die and RCBS seating die along with the Lee FCD. Also adjusted the shell plate bolt to make sure there was no play in the shellplate. The case bulge does not happen on every case just about 20% of the time. I use a Lyman cartridge gauge to check the loaded shells after processing. The loaded ammo looks right, but you can sometimes feel a slight bulge at the shoulder. It is just enough to make the AR bolt fail to fully close; when I check the round in my bolt action, the bolt has some resistance before closing. I have not been able to find a similar issue in the forum. Wondering what I am doing wrong and if anyone has suggestions for a solution.
I started loading 223 for my AR on the 550C. I am getting an occasional case with a mild bulge at the case shoulder. I have adjusted the sizing die up and down; powder die up and down; seating die up ( so it does not crimp the bullet) and have a Lee Factory Crimp die in station 4. I am using a Dillon Carbide sizing die and RCBS seating die along with the Lee FCD. Also adjusted the shell plate bolt to make sure there was no play in the shellplate. The case bulge does not happen on every case just about 20% of the time. I use a Lyman cartridge gauge to check the loaded shells after processing. The loaded ammo looks right, but you can sometimes feel a slight bulge at the shoulder. It is just enough to make the AR bolt fail to fully close; when I check the round in my bolt action, the bolt has some resistance before closing. I have not been able to find a similar issue in the forum. Wondering what I am doing wrong and if anyone has suggestions for a solution.
Quote from The Human Manual on May 12, 2025, 3:55 pmThe bulging is probably occurring at the crimping station. Use a headspace case gage to adjust the size die for minimum headspace. you probably need to back the factory crimp die up 1/4 turn or more.
The bulging is probably occurring at the crimping station. Use a headspace case gage to adjust the size die for minimum headspace. you probably need to back the factory crimp die up 1/4 turn or more.