Redding Bushing Sizing

grndslam

Active Member
Joined
Sep 7, 2010
Messages
29
Location
Santa Fe, NM
Ok guys totally new to reloading. Thought I would learn/start with my Rem 700 30-06. I have some once fired Hornady Brass whose outside neck diameter is .341 My factory ammo's outside neck diameter is .333 I'm using a Redding FL Type S die. I have a .332 bushing. From reading various forums it seems that to go from .341 to .332 in one step is a little much and I should get a .336 bushing as a first sizing then to .332 for the final sizing. Is this correct and is it common.

Thanks

Darrin
 




I subtract .003 (.002 neck tension + .001 spring back) from the loaded round diameter and order that size plus .001 smaller and .001 larger. Since you already have a .332 bushing, I would give it a try and see if it works for you before ordering others.
 
Is your factory loads that you measured to be .333 and your brass the same brand and lot?
If not then you can't measure the factory round and use that dimension to find a bushing for your once fired brass. Was the once fired brass fired in your gun or was it acquired from another source?
If it were me I would size one piece with the bushing you have and seat a bullet with no primer or powder and measure it and then do as just_jon suggested.
 




I subtract .003 (.002 neck tension + .001 spring back) from the loaded round diameter and order that size plus .001 smaller and .001 larger. Since you already have a .332 bushing, I would give it a try and see if it works for you before ordering others.

I go with .003 smaller and then run through a mandrel at .002, so pretty similar, both between .002 and .003 with springback. I anneal after every firing.
 
When I was using bushings, I would go 001", .002", .003" & .004" under measured brass necks. 9/10 the .002" was the sweet spot.
Only one of my barrels likes .004" IF.
None of these measurements I am quoting take into consideration spring back.

Cheers.
 
To answer your question - yes, that's correct. It's best not to reduce the diameter more than 0.004" per step.
 
Ive necked down hundredsof 223 brass for my 20 practical in one step with zero problems and I know alot of other people do the same thing, I dont it will hurt a thing. If your worried about it anneal your brass, I would anyway no matter if you do it in 1 or 2 steps your gonna be working the brass alot everytime you size the brass.
 
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