Testing hand loads seated mag depth with Lee Factory crimp die .308

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DG Photography

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Here are my targets from testing the Lee Factory Crimp die all seated to mag depth. Brass was trimmed within .002" of each other, primer pockets not uniformed but cleaned, cases SS tumbled and annealed, necks sorted by inside neck guage as brass is on 6th firing and some necks are getting a little thick so I try and sort them. Rifle is Sako TRG 22 26" barrel groups shot off LRA bipod rear sock off bench.

 
Wow DG! Great groups and I notice that the POI does not shift meaningfully between your groups. I bet you could get a 10-20 round 1/2 MOA group. Any tweaks to your TRG?

Also, do you find the factory crimp improves your loads? I abandoned crimping myself having found no evidence of accuracy improvements.
 
I only crimp when seating mag depth for mag feeding. When hanging closer to the lands I use no crimp and .0015-.0025" neck tension. Here is my playing with different crimp tensions and two different projectiles (175gr SMKs and 167gr Scenars also different neck tensions. Some groups were shot with different crimp tensions mixed in notice the 200y lowe left group two fliers opened the group up the two fliers were heavy crimps the group size recorded was for the 5 shots of same crimp tension.



 
I'm not surprised, I fully expect crimped rounds to shoot worse, and bullets that are crimped without a crimping groove to shoot worse than that. I don't know how Lee dreamed up the idea that squashing a bullet was a good idea.

Good shooting BTW.
 
The medium crimps work well when seated mag depth and you are mag feeding fast. The best groups were crimped! Now if you are going to hang the projectile near the lands IME no worky so good. Heavy crimps were no good you could see it well at 200y the heavy crimp fliers of the lower left group and the .6 group in the middle were medium/heavy. When I was at a good accuracy node the Lab Radar was falling to 10fps spread with crimped rounds this is good for no neck turned and slight neck thickness variance did not sort real anal and did not toss lobsided thickness in necks.
 
Dogleg said:
I'm not surprised, I fully expect crimped rounds to shoot worse, and bullets that are crimped without a crimping groove to shoot worse than that. I don't know how Lee dreamed up the idea that squashing a bullet was a good idea.

Good shooting BTW.
Click to expand...

Thanks!

Only time I would crimp is seating mag depth while mag feeding light-med crimp and especially when testing gas guns.
 
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