The Firing Line Forums - View Single Post - Lee 4 Die set for 9 mm

Lost Sheep · October 9, 2011, 02:18 AM

As Sevens (and others) have said, the "springback" phenomenon is real. Not usually significant, but it can be.

There is an easy cure. Don't post-size.

There are two ways to accomplish this. Knock the post-sizing ring out of the FCD or use a separate seat/crimp die with the seating post adjusted out (or removed).

Most of the time combining the operations in the seat/crimp die creates no problems. But if it does cause problems with your ammunition (or you just want to simplify your die adjustment process), handloading with four operations instead of three will cure them.

For me, adjusting the seat die and crimp die separately is not that much easier than making the adjustments in a single die. But the biggest advantage is that I can apply whatever degree of crimp you want without concern over the bullet moving as you crimp, which ALWAYS happens when you combine the seat/crimp operations (though, as I said earlier, not always causing problems).

Thanks for reading,
Lost Sheep

October 9, 2011, 02:18 AM	#12
Lost Sheep Senior Member Join Date: January 24, 2009 Location: Anchorage Alaska Posts: 3,341	Three steps or four? As Sevens (and others) have said, the "springback" phenomenon is real. Not usually significant, but it can be. There is an easy cure. Don't post-size. There are two ways to accomplish this. Knock the post-sizing ring out of the FCD or use a separate seat/crimp die with the seating post adjusted out (or removed). Most of the time combining the operations in the seat/crimp die creates no problems. But if it does cause problems with your ammunition (or you just want to simplify your die adjustment process), handloading with four operations instead of three will cure them. For me, adjusting the seat die and crimp die separately is not that much easier than making the adjustments in a single die. But the biggest advantage is that I can apply whatever degree of crimp you want without concern over the bullet moving as you crimp, which ALWAYS happens when you combine the seat/crimp operations (though, as I said earlier, not always causing problems). Thanks for reading, Lost Sheep