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Matt Anthony
05-05-2014, 03:48
Yesterday I decided to clean up the yard instead of my usual trek to the range for Sunday morning pill shooting. I knew the yard needed it and it turned out to be a perfect morning for that. You can't start the mower and vac until at least 9AM so I had 4 hours to kill. I decided to load up some 185 gr. Hoch nose pour bullets for one of my 30/06's. Using 14 gr's of Green Dot I loaded 50 rounds and then seated the bullets using an RCBS seating die. I would normally on Jacketed use the Wilson straight line die, but cast won't work in the Wilson, so the RCBS would have to be used. When seating these types of bullets I like to be right at the lands or just below, no more than .010 from the lands, so seating is determined with a dummy round. Taking a cast bullet after using the Lyman M die and seat it long. Now take the round and load it, seating the bullet against the lands with your bolt. Now take the round out of the chamber, install it in your press and seating die and adjust it to touch the bullet. Now take a loaded round, seat a bullet.
Loading a live round in a rifle at home can be tricky, so if you have the type of bolt where you can put the safety on and still load and eject a cartridge, like the M70 Winchester, then your in luck. I normally take my firing pin assy's out of my M700's just to be safe.
Now that you have the round seated, set up the Hornady Concentricity tool to ride on the band next to the neck. You will be surprized how far off your rounds are, even when using the M die. I have tried different brand seating dies, competition to regular branded dies and they all fall short on the concentricity issue. Follow directions provided with the tool and by all means use dummy rounds to practice on before using your completed ammo. Once you get the knack of straightening, you will be able to adjust it under .001 to perfect on one try. Since all of your components are the same, you will see that most if not all are out of round the same spec. The one's I did yesterday were .002 to .003 off. I was able to put them all under .001.
So what does this labor operation do for you? Well, a straight round going into a chamber will fly true when fired as the round is concentrict with the bore. This is why I can group cast bullets just as good as jacketed. Once I started using this tool on both jacketed and cast, it produced a significant reduction in group size, so much that now I can brag that cast bullets can group just as good as jacketed. This tool changed my reloading world.......I would not be without it.
Matt