I'm a little confused by Reddings bushing range chart for their S type dies in 300WSM and using these dies. The website says .335-.343 bushings for this load. I'm using Winchester brass that measures .342 when shot. Brass thickness is .014 and my reloads are coming in at .334 using standard dies so I assumed I needed a bushing .001 to .002 smaller. Something doesn't seem to jive (.014+.014+.308) = .336. Where am I going wrong?
Redding bushing range chart
- Thread starter boomhand
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Mikecr
Well-Known Member
Well it never never really matters what charts and manuals imply, when you measure otherwise..
Pay em no mind
You're right about going a ~2thou under loaded neck ODs.
The reason for the discrepancy in math, sounds like brass thickness measurement while necks are under-cal in size. When necks are then expanded by bullet seating, the necks thin to 13thou thickness -> (0.334-0.308)/2
This, provided your bullets actually measure .308(there are .307 bullets).
Pay em no mind
You're right about going a ~2thou under loaded neck ODs.
The reason for the discrepancy in math, sounds like brass thickness measurement while necks are under-cal in size. When necks are then expanded by bullet seating, the necks thin to 13thou thickness -> (0.334-0.308)/2
This, provided your bullets actually measure .308(there are .307 bullets).
Mikecr
Well-Known Member
Yes, 14thou is normal.
You do have excess neck clearance though(from .334 neck OD to ~.343 chamber neck(springing back to .342). So with a .332 bushing for 2thou under loaded necks, you'll be sizing down 10thou(.342-.332). This is a lot for bushings to do in one step.
It'll work, the S-Type will expand the necks back out some.
But it might not work out so well, and there ain't much you can do about it.
In other words, you might be forced to FL size the necks(at least partially).
You do have excess neck clearance though(from .334 neck OD to ~.343 chamber neck(springing back to .342). So with a .332 bushing for 2thou under loaded necks, you'll be sizing down 10thou(.342-.332). This is a lot for bushings to do in one step.
It'll work, the S-Type will expand the necks back out some.
But it might not work out so well, and there ain't much you can do about it.
In other words, you might be forced to FL size the necks(at least partially).
