Hello, I've never done it before, never had to, but when I talked to my B-I-L about how the 300WSM shot, he told me alot of them were going in kinda hard, he was thinking it was the 180 Ballistic tips, I told him they were all within spec as far as oal, 2.830", one actually wouldn't allow the bolt to be closed, I'm thinking maybe the shoulder needs to be pushed back, but why, these are new brass, they should be all at factory spec ready to go except for the mouth to be straightened out, which I always do, then do the chamfering, the rifle is a Browning A-bolt, what's been your experience as far as new brass goes, or is it a tight Browning chamber that's at fault? Jay

Beemanbee, I usually shoot 3 shot groups with magnum hunting rifles, the benchrest matches I've shot in were for 10 shots. Obviously a gun that will shoot 1/4" for 10 shots is in another league than one that will do it for 3. Also you might realize that there is a big difference in 1/4 to 1/3 MOA and 1/4 to 1/3". I don't have any hunting rifles that will shoot 1/3" groups at 300 yards but I do have a few that have shot sub .9" (apx 1/3 MOA) 3 shot groups at 300yds...............DJ

Jay--I'm curious--I live a block away from Bob. If they'd like.... have them drop off:

a fired case.
The one that wont got into the chamber
And one that will go into the chamber freely.

I'll measure them with my stoney point head space tool and drop them all back off at Wadale. Kraky

I full length size all new brass. That is probably the only time it will be full length sized. I find the quality of new brass today to be little better than crappy. After the brass has been fired in my rifle I only work with neck sizers, preferrably bushing dies or Wilson knock out dies.
It's a little extra work sizing new brass but usually worth it. Best wishes.

Cal - Montreal

YES! Size em all. I made the mistake of not sizing some new 375 H&H brass. The bullets were actually loose when seated?
Accuracy suffered because I did not size the new brass.

I usually run new brass about .200 of the neck into a die to round up the neck. The expander pushes out the factory tumbling burrs on the case mouth on the way back out. Then I deburr the cases to remove any divots on the edge so the case has little tendency to split.

I never have. I just grab a couple of cases and make sure they'll chamber (they always have) and then I bump the expander ball thru the neck, chamfer the inside of the neck, and load 'em up and shoot 'em. Occasionally, I have to use the shank of a screwdriver to round the mouth of the cases enough to use the expander ball but that's it.
After I've fire formed the brass, I do all the toughy-feely stuff like trimming to a uniform length, etc.

I always resize before I load new brass. Your B.I.L.'s 300 WSW may just have a minimum spec. chamber that is causing the bolt to close hard. Is the brass by chance Norma brass? I a 300 WSM match rifle built on a Remington action that I use for 1000 yard F class competition. This rifle has a S.A.M.M.I. minumum spec chamber and the unsized Norma brass would not chamber. I had to bump the shoulder back and it works just fine now. The Winchester Coyotes that are chambered in 300 WSM tend to have a pretty tight chamber as well, or at least the 3 of them I have been around have had. The next time you load for him have him bring the rifle over and keep bumping the shoulder back slightly till they chamber correctly. If the OAL is at 2.830" I have a hard time believing that the OAL is the problem.

Hope this helps some.

RiverRat

I don't do it any more but when I did it I NEVER had any brass that was large enough to even touch the die anywhere but at the neck. I found it to be a big waste of time and I've never had a new case not chamber in a gun. Certainly the factory ammo isn't full sized either. Most unbelted cases have the shoulders set back .004" from minimum SAAMI specs. Belted mags are set back anywhere from .014" to as much as .030". How is a FL die going to do anything except at the neck?

"Need" to FL size - maybe, maybe not. Nice to know that all of your brass is exactly the same - definitely. I prefer not to waste bullets in cases that haven't been properly prepped. Complete case prep may not be always necessary but I do it anyway since it might. I like to remove all possible negative variables that are in my control to fix.......DJ