Author: Goosic
Subject: Case Neck Concentricity
Posted: June 27 2023 at 8:02am
(After the initial case prep has been done.) I have been taking once fired 7.62 Lake City brass and using a Lyman .243W full length resizing die to neck the LC cases down. Each case takes 4 short strokes of the ram to get the desired case formation with the case being rotated 1/4 turn with every throw of the ram arm. After the cases are full length resized I will use a 6mm bronze bore brush on an electric drill and score the inside of the neck. After that has been completed I will run each case through the .243W Lee Collet Neck sizer with a .002" undersized mandrel twice, rotating the case 180°. The brass then gets a 1 hour run through dry media. The final step after being polished has me running the case through the neck sizer one last time. The cases are then primed and loaded with 2.46g/37.9gr of VihtaVuori N540 using a Lyman 2.2g dipper and then scaled out with a trickle charger. The bullet of choice is the HPBT Lapua 6mm 90grn OTM Scenar-L. The case neck concentricity shows zero runout. The bullet seating tension expands the case neck outwards by .003" and allows me to seat the bullets out to 2.710" with zero to .0001" bullet runout.
Subject: Case Neck Concentricity
Posted: June 27 2023 at 8:02am
(After the initial case prep has been done.) I have been taking once fired 7.62 Lake City brass and using a Lyman .243W full length resizing die to neck the LC cases down. Each case takes 4 short strokes of the ram to get the desired case formation with the case being rotated 1/4 turn with every throw of the ram arm. After the cases are full length resized I will use a 6mm bronze bore brush on an electric drill and score the inside of the neck. After that has been completed I will run each case through the .243W Lee Collet Neck sizer with a .002" undersized mandrel twice, rotating the case 180°. The brass then gets a 1 hour run through dry media. The final step after being polished has me running the case through the neck sizer one last time. The cases are then primed and loaded with 2.46g/37.9gr of VihtaVuori N540 using a Lyman 2.2g dipper and then scaled out with a trickle charger. The bullet of choice is the HPBT Lapua 6mm 90grn OTM Scenar-L. The case neck concentricity shows zero runout. The bullet seating tension expands the case neck outwards by .003" and allows me to seat the bullets out to 2.710" with zero to .0001" bullet runout.
My oldest daughter asked me why it takes me so long to reload 50 to 100 cases. My response was to purposely try to make a question mark after I shot the cartridge case at a distance of 100 yards. The extra time involved with case prep and weighing out each charge is definitely worth the time and effort. The Jap made Weatherby has been taken to Bergers 1000 yard range and produces sub-moa groups consistently and I truly believe that it is due largely in part to the bullet selection, weighing out of each charge and what some would call unnecessary case prep work with me being the redundant component.![]()
After the fire formed cases are set to be reloaded, it is then that I use the Lee-Loader "Whack-A-Mole" from that point forward. ![]()
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My daughters targets they shot at a distance of 200 yards for reference...![]()
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After the fire formed cases are set to be reloaded, it is then that I use the Lee-Loader "Whack-A-Mole" from that point forward. 
My daughters targets they shot at a distance of 200 yards for reference...
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