How much chamfer with a Giraud??

[DngBat7]

I guess this may apply to any sort of trimmer, But how much of a chamfer to you want when using the Giraud power trimmer. Since the triangle blade can be moved, You can have anything from a mild chamfer or a pretty dramatic chamfer to where the case mouth is a sharp edge. Is either wrong? Or right for that matter?

thank you

 

[D-4297]

The main purpose of the chamfer ; on the inside , is to act as a "ramp" to guide the bullet into the neck , and hopefully avoid any damage to the bullet jacket / plating . The chamfer also removes any burr that may be in the neck from tumbling . Anywhere from .010 to .015 in height is workable for the purpose , and it doesn't need to be taken to the sharp edge extreme . That will only add to the problem on the next prepping cycle . Outside chamfer should be no more than to remove any burrs for the purpose of protecting your Dies . From the FWIW Dept. ; I always chamfer both inside and out on case-mouths before re-sizing , so as to eliminate damaging my Dies from burrs or brass build - up .

 

[ronemus]

Since the cutter geometry is fixed, reducing the inside chamfer will increase the outside chamfer. I choose to use a minimal outside chamfer, just enough to remove any bur. That gives me an inside chamfer ~0.015" tall which I don't consider to be excessive; it certainly makes it easy to seat moly-coated BTHPs without removing the coating. The width of the flat on the case mouth is fixed unless you set it far enough out that you no longer debur the outside, which I would not consider desirable.

 

[Ned Ludd]

The bottom of the v-blade is radiused, so it does not cut a "knife edge" around the case mouth no matter how you have it set. I set mine so the there is a healthy chamfer on the inside, and the outer corner is just slightly knocked off on the outside.

 

[Straightshooter1]

I set mine so the there is a healthy chamfer on the inside, and the outer corner is just slightly knocked off on the outside.

Ditto with my Giraud