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WYcoyote
12-14-2010, 08:12 PM
I need some switch barrel veterans to tell me if this will work to set my headspace to match my Forster FL benchrest dies to minimize brass fatigue and maximize case life. Caliber will be 6.5-.284 Norma.
I plan to set the barrel using a Forster go guage and tighten the nut. I have some ss shim stock, I will cut a piece and place between the bolt face and go guage to use it for a no-go.
Then I plan on shooting one round, and full length size the fired case. (new Lapua brass)
I will then reset the headspace using this piece of brass, and use a shim again to check no-go.
A few questions:
This proceedure GTG?
How thick of shim to use? ( I have all .001" increments available)
Will I realize any advantage? Should I just skip the headspacing to the brass and just use the guage?

Blue Avenger
12-14-2010, 08:38 PM
you will have the best "fit" with that plan. only drawback is a slim chance factory ammo will not work. Not much chance of you shooting that though. You do have to watch that the bolt head dose not hit the barrel and give a false reading. I had that happen last night when I put on a .25-06 barrel I just got. Have not gotten around to measuring where I have to make a change. Never had it happen before, but noticed I had the same drag with an empty chamber. Remembered some one saying something about checking for contact.

bigedp51
12-14-2010, 08:51 PM
I would use the GO gage as a reference and measure the brand cases you plan to use and see how much shorter new unfired cases are compared to the go gauge. In my last batch of .243 cases some of the cases were .007 shorter than minimum headspace or the GO gage. On average a new case will be approximately .002 under minimum headspace so I would just set the headspace with the GO gauge "OR" tighter if you want to lap your shell holder for a custom chamber fit.

If you are going to use the rifle for hunting I would keep the rifle within headspace standards and not go more than .003 over GO or minimum headspace.

Food for thought, once you fireform your cases the actual headspace setting becomes a moot point.

Below, you can shim your dies or "shim" the bottom end and use custom shell holders to keep from overworking your brass.

http://i122.photobucket.com/albums/o254/bigedp51/7-17-201054719PM.jpg

http://i122.photobucket.com/albums/o254/bigedp51/7-17-201054345PM.jpg

Cover Dog
12-14-2010, 10:48 PM
This is an excellent article by an excellent shooter. He knows what he is talking about.

http://riflemansjournal.blogspot.com/2009/08/reloading-headspace.html

BobT
12-20-2010, 12:28 PM
Sorry for the late response, I'm not on everyday any more. That is how I set up all my Savage bolt actions. I set my sizing die to just cam over in the press and resize a fired case at that setting. Fill the fired case with epoxy and let that set up and you have your new "go" gauge. I use .002 shim stock for the no go. Factory ammo usually won't chamber but I load all my own anyway so it's not a problem. I get maximum case life this way and don't need to spend a bunch of time setting up dies, just screw them down and go.

Bob