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**Unclenick** · August 25, 2012, 01:23 PM

The military uses bullet pull as its measure. The STANAG drawings for 7.62×55 (.308 Win) show 60 lb pull for both brass and steel cases. Unfortunately most folks don't have an easy means to measure this directly. You can try improvising by using a fish scale to operate your press handle while using a collet type bullet puller in the press. I haven't actually tried this, so I don't know what numbers you'll come up with. They should give you some comparative sense of the effect of your crimps.

Dwayne,

A few things come to mind. One is that the Lee seater may be designed for Spitzer bullets and be counting on the pointed tip to help align the seater ram. I don't know. The way the Lee Dead Length seater works is the stem floats a little to self align.

If you continue to have a problem you need to check the runout of the necks themselves after resizing. You can straighten these just by drilling a hole slightly over neck OD into your bench and sticking the neck in and applying light pressure to straighten it. It takes a little practice, but isn't difficult.

The other thing you can do is buy the Lyman 30L M die for 7.62×54R. This adds a step (expanding) to reloading, but causes bullets to start in straight and tend to stay more straight.

My other thought is about your brass shortening. If you are firing loads below about 30,000 psi, cases can actually shrink rather than grow. Growth depends on the pressure being high enough to stick the brass to the chamber walls so the head has to stretch the brass where it meets the case wall in order to get back against the breech face. Resizing sets the shoulder back from that stretched case body shape, which flows the extra shoulder brass into the neck, causing length to increase. When you shoot at pressures too low to make the brass stick to the case walls, the head is moved to the breech face by the whole case just backing up in the chamber. When that happens you can actually blow the bottom of the neck out into the shoulder a little. That shortens the neck, and resizing may not fully restore length afterward.

One solution to the above situation is to go to neck sizing only. If you are firing at low pressure, then the case won't expand as much as it does firing at full pressure anyway, so you should get good function and longer case life by neck sizing. Because the case shoulder isn't being pushed back by the neck sizing die, a neck sized case should stop backing up and shortening the neck at each firing. Also, this is an opportunity to learn to use the Lee Collet Die, which neck-sizes without introducing neck runout (see this video).

August 25, 2012, 01:23 PM	#8
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	The military uses bullet pull as its measure. The STANAG drawings for 7.62×55 (.308 Win) show 60 lb pull for both brass and steel cases. Unfortunately most folks don't have an easy means to measure this directly. You can try improvising by using a fish scale to operate your press handle while using a collet type bullet puller in the press. I haven't actually tried this, so I don't know what numbers you'll come up with. They should give you some comparative sense of the effect of your crimps. Dwayne, A few things come to mind. One is that the Lee seater may be designed for Spitzer bullets and be counting on the pointed tip to help align the seater ram. I don't know. The way the Lee Dead Length seater works is the stem floats a little to self align. If you continue to have a problem you need to check the runout of the necks themselves after resizing. You can straighten these just by drilling a hole slightly over neck OD into your bench and sticking the neck in and applying light pressure to straighten it. It takes a little practice, but isn't difficult. The other thing you can do is buy the Lyman 30L M die for 7.62×54R. This adds a step (expanding) to reloading, but causes bullets to start in straight and tend to stay more straight. My other thought is about your brass shortening. If you are firing loads below about 30,000 psi, cases can actually shrink rather than grow. Growth depends on the pressure being high enough to stick the brass to the chamber walls so the head has to stretch the brass where it meets the case wall in order to get back against the breech face. Resizing sets the shoulder back from that stretched case body shape, which flows the extra shoulder brass into the neck, causing length to increase. When you shoot at pressures too low to make the brass stick to the case walls, the head is moved to the breech face by the whole case just backing up in the chamber. When that happens you can actually blow the bottom of the neck out into the shoulder a little. That shortens the neck, and resizing may not fully restore length afterward. One solution to the above situation is to go to neck sizing only. If you are firing at low pressure, then the case won't expand as much as it does firing at full pressure anyway, so you should get good function and longer case life by neck sizing. Because the case shoulder isn't being pushed back by the neck sizing die, a neck sized case should stop backing up and shortening the neck at each firing. Also, this is an opportunity to learn to use the Lee Collet Die, which neck-sizes without introducing neck runout (see this video). __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle