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neal
03-15-2008, 08:54 AM
When loading for .308 with 168 gn. Serria's is it best to chamfer with the old .45 degree tool or with one of the new ones such as 14 degrees?

cdupuy
03-15-2008, 11:20 AM
neil:
I would use the 45 degree as I have seen additional TIR when using the VLD tool, the difference is .0005 TIR with the 45 and .002 for the VLD tool.
Remember if (Sierra 168) stay undert 800 with it.

Clarence

neal
03-16-2008, 10:01 AM
Ok I may learn something new here. What is TIR am not sure that I have heard the term before.

Ted Winterman
03-16-2008, 10:22 AM
To my understanding, TIR is TOTAL INDICATED RUNOUT. I have been
using a LYMAN 22 degree inside mouth chamfering tool. It is a great tool
for splitting the difference between other tools. For outside chamfer I use
the standard 45 degree tool.

Tbear:)

John Kielly
03-16-2008, 06:23 PM
After reading a number of threads on various forums, I've concluded that it is far easier to cut roughly with the 45 degree tool, leaving shavings which can damage the projectile when seating it. In an extreme case, the sloppy chamfering was so rough in a .223 that the user tore lumps off the projectile & severely marked the ogive with the seating plunger, such was then necessary seating force.

I guess you could remedy that shortcoming by polishing the neck inside after chamfering, but that would seem to be a tad tedious & imprecise to me. I'm happy to take my chances with my K & M & a minimum cut enough to just break the 90 degree shoulder. After all, the boattails I use don't take much encouragement to get past the case mouth.

neal
03-16-2008, 08:01 PM
Thanks for the info guys. I have both the old 45 degree as well as one of the new ones from Sinclair.