edwardware
Member
- Joined
- Feb 23, 2010
- Messages
- 4,421
I'm reloading for a Rem 700 .223 bull barrel, and my latest rabbit trail is concentricity. It's always seemed that I had an uncontrolled variable somewhere causing good recipes (0.4-0.7" @ 100) to start throwing fliers. Over the course of a year, ~1000 reloads, 5 bullets, 2 powders, etc, I haven't found a recipe that's reliably under 1".
So I built a concentricity gauge, and lo and behold, my expander ball was pulling necks 0.004-0.008 off centerline, with seated bullet runout varying up to 0.010 at the leading edge of the bearing band. I bought a neck turning setup, polished the expander ball, and bought a Redding Competition Seater (ouch!). I've just finished the first batch: LC-13 brass, FL sized, outside neck turned necks to 0.011", annealed, FL resized to 0.002" tension, checked neck concentricity, and culled any over 0.001".
Now I've seated a couple bullets (in the Redding Comp Seat), and the eccentricity is back!
Is it really normal that seating (in a Redding Comp Seater, no less) should double runout on the neck, and triple it on the bullet? What am I missing here? This was a lot of work for on a ~30% reduction in runout.
So I built a concentricity gauge, and lo and behold, my expander ball was pulling necks 0.004-0.008 off centerline, with seated bullet runout varying up to 0.010 at the leading edge of the bearing band. I bought a neck turning setup, polished the expander ball, and bought a Redding Competition Seater (ouch!). I've just finished the first batch: LC-13 brass, FL sized, outside neck turned necks to 0.011", annealed, FL resized to 0.002" tension, checked neck concentricity, and culled any over 0.001".
Now I've seated a couple bullets (in the Redding Comp Seat), and the eccentricity is back!
Is it really normal that seating (in a Redding Comp Seater, no less) should double runout on the neck, and triple it on the bullet? What am I missing here? This was a lot of work for on a ~30% reduction in runout.