I made up a little system that works well for me and I've been using it for years....
My system consists of the following:
1. An appropriate length cleaning rod
2. A brass jag with a flat tip
3. Washers (2) that are the same thickness that slide over the rod and can be fixed in position using nylon tipped set screws..
This image is hidden for guests.
Please log in or register to see it.
Remember - Every bullet style will result in a different over all cartridge length. When developing a load for a particular rifle your initial measurements must be used using this tip to determine the chambers
Maximum Overall Cartridge Length. The tip of each bullet is not the same therefore if you're measuring the cartridge overall length it will be different with each cartridge and you'll be chasing your tail trying to figure out what's wrong. The Ogive on the other had is pretty consistent within a given lot of tips therefore can be used as a repeatable datum with adjusting the seating die.
Maximum Overall Cartridge Length = Distance from the bolt face closed to the tip of the bullet just touching the rifles lands.
Instructions:
1. Slide the first washer on the cleaning rod.
2. Screw the brass jag into the cleaning rod tip
3. Slide the cleaning rod assembly into the muzzle end of the barrel until it comes in contact with the bolt face
4. Slide the washer against the muzzle and tighten the set screw
5. Remove the cleaning rod assembly and add the second washer
6. Remove the bolt
7. Insert the bullet tip into the chamber until it touches the lands.
8. Hold the bullet against the lands with a wooden dowel so it won't move
9. Slide the cleaning rod assembly into the barrel until it comes in contact with the bullet tip.
10. Slide the second washer up against the muzzle and tighten its set screw.
11. With a vernier, measure the distance from the outside of each washer
12. Subtract one washer thickness...
Result =
Maximum Overall Cartridge Length
Generally speaking, I like to have about 0.010" gap between the Ogive and the lands. This allows "some" bullet movement so that chamber pressure drops as soon as the cartridge is fired. "Jamming" the Ogive into the lands can cause a dangerous pressure spike if you're working with a maximum load.
Using the bullet above, adjust your seating die until the tip of "this" bullet in a loaded case equals the determined cartridge maximum length minus 0.010. The relative distance from the head of the cartridge to the bullets Ogive
should remain constant within 0.002, all else being equal....
In general, the
Maximum Overall Cartridge Length will exceed the magazines allowable length and will need to be loaded individually.
Topic Author
