How much case length growth measured base to shoulder should one expect with first firing?

[tnek13]

I have ended up with multiple sizing dies for a couple of calibers I load for. To avoid that expense - Do you have a friend that shoots the same caliber? if so see what die he uses and see if you can give it a try on your brass. If not, the Redding full-length sizing S dies seem to work best for me with the appropriate bushing and with the expander removed.

 

[30BR]

Depending on the reamer used, it's not unusual to have headspace shrink upon initial fireforming. Especially if you use a subdued powder charge. The case gets blown out before it grows. Usually after the 2nd firing, the brass is happy, but I've seen some require 3 firings to settle down. Now maybe that's just me, because I don't like to shock my expensive brass that I've prepped for hours on it's first firing. I like to sort of sneak up on it.

 

[oneeyejohn]

I have had this problem when changing from a long sloppy factory chamber to a shorter tight match grade chamber. I ground of the bottom of the die to allow me to screw it down enough to bump the shoulder back to fit my chamber. You can adjust the die to fit different makes of brass if needed. I have never had a case problem using this method of adjusting the die.

 

[Reloader222]

That shell holder set seems to be a good idea. My 30-06 also grow cases to 0.004". I have adjusted my sizer die to bump the shoulders only 0.002". This is important to prolong the life of the case.

 

[Vol1975]

Reamer and smith dictate this.
had some work done recent and the head space is pretty tight. .002 in growth. I'm use to more of a factory job with growth in the neighbor of .005-.006. The custom Reamer was from JGS. Gun loads factory brass and I can bump it back But growth is minimal at best.
go and no go gauges are good. It just tight.

end of the day it's a shooter. Just not use to the small amount of head space.

 

[gohring3006]

The brass may not be formed to the chamber with the first firing. I won't set up a die before the third firing. I neck size the first two firings

 

[barefoot1]

[QUOTE="Bob Wright, post: 1975185, member: 10436 you can buy a set of shell holders from Redding that will accomodate your chamber. They vary in increments in .00x increments to set the brass deeper into the die. It's just for this problem. I believe there are about 10 shell holders in the set.

Just so everyone is clear The Redding competition Shell holders do just the opposite they keep the case from going into the die as deep as a standard shell holder.
A standard shell holder is .125 height While the Redding Competition Shell holders start at .127 and go in +.002 increments up to .135 in height.
To push the case deeper into the die for more sizing you would need to remove material from the top of the standard shell holder or remove some from the bottom of the die.
[/QUOTE]
These things work very well. Just got the caliber specific dies with the extended shell holders for 6.5 CM, 7mm Rem Mag, and 300 WIN MAG.

 

[barefoot1]

Using Lapua brass to develop a new hunting load for my XBolt in 6.5CM and that Lapua stuff barely / did not at all expand after first firing. Will see what happens on second firing.

 

[SheepSeeker]

Competition Shellholder Sets
Makes every die a custom die!

Now you can control headspace. The new Redding Competition Shellholders are packaged in five piece sets in .002" increments (+.002", +.004". +.006", +.008" and +.010"). Each shellholder has a distinct black oxide finish and is clearly marked to indicate the amount it will decrease case-to-chamber headspace. You can now easily adjust the shoulder bump to customize cases to your specific chamber.

 

[SheepSeeker]

Very clear that these shell holders are made to adjust the headspace of the brass by SHORTENING the shoulder to base dimension

 

[BoomFlop]

Sheep Seeker,

You have it backwards. The Redding Shell Holders do not size the brass more than a stand .125 shell holder. They just allow you to make adjustments without backing the die out.

Have a great day,
Steve

 

[barefoot1]

Yes I see how that could have been misinterpreted. I am using them to "bump" shoulders back not expand them more than unfired brass.

 

[jimbires]

watch the video from 2:09 - 2:15 . Broz says to start with the .010 shellholder it sizes the least . maybe you guys will believe him . I said the same thing in post #10 .

 

[Bob Wright]

Redding could have re-worded their ad. The video tells the story well.

Much better than grinding down shell holders. Running precision grinding equipment in my early aerospace days tells me doing it by hand is making other problems appear. Unless we all had surface grinders.....