Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Reloading

Reloading Techniques For Reloading


Reply

adjusting head space

 
LinkBack Thread Tools Display Modes
  #1  
Old 04-13-2006, 12:56 PM
Silver Member
 
Join Date: Feb 2006
Location: Pueblo, CO
Posts: 286
adjusting head space

How does one adjust headspace on standard RCBS dies (I know, I need to upgrade), I'm using the stony point headspace gauges and I just want to bump the shoulder back .002". Do I set it up so the die is no longer camming on the shell holder and keep backing it out till I get the desired bump?
Reply With Quote
  #2  
Old 04-13-2006, 03:00 PM
Platinum Member
 
Join Date: Dec 2005
Posts: 2,114
Re: adjusting head space

Yes.

I've got six .308 Win. full-length RCBS dies. When any one die is locked in one of three presses, the clearance between the same shell holder to the bottom of each die for what's needed to set shoulders back .002-inch varies several thousandths of an inch.

All dies and presses are not made to exact specs. Tolerances prevail. Your die and press may end up with the die just clearing the shell holder without a case in it. Or there may be a bit of contact. I've measured the "headspace" in those dies with a GO headspace gage for chambers to see how far the gage protruded out the bottom of the die; they all ain't the same.

Plus, I don't think there's anything wrong with those RCBS dies.
Reply With Quote
  #3  
Old 04-13-2006, 07:21 PM
Silver Member
 
Join Date: Nov 2004
Location: Shiro, TX
Posts: 102
Re: adjusting head space

Esentially yes you adjust the depth of the die to get the desired shoulder bump. Its hard to believe that reloading books just say to set the die adjust for where it slightly bumps the case holder. This does vary greatly and until I began measuring I was bumping some back .010" while some dies were not even bumping at all! So yes the dies are very inconsistent. I even had to have a Redding sent back to have the bottom cut down so I could touch shoulder at all. The right way is to measure it then lock the ring on the die and bingo your set.

Lance
Reply With Quote
  #4  
Old 11-01-2008, 09:14 AM
Silver Member
 
Join Date: Dec 2007
Posts: 297
Re: adjusting head space

bear with me here so head space will only fall in to the game when reloading not with factory ammo so there is nothing I can change on my rifle other than replacing the bolt and checking with one of them stop and go dies I think that is the right name
Reply With Quote
  #5  
Old 11-01-2008, 05:22 PM
Platinum Member
 
Join Date: Oct 2007
Location: Mountians of SW NC, near Asheville
Posts: 1,596
Re: adjusting head space

"How does one adjust headspace on standard RCBS dies (I know, I need to upgrade), I'm using the stony point headspace gauges and I just want to bump the shoulder back .002". Do I set it up so the die is no longer camming on the shell holder and keep backing it out till I get the desired bump?"

Okay, first you have no need to "up-grade" anything, your dies are fine.

Most people FL size the "right way", as the die insructions say and that is by screwing the die down to firm contact with the shell holder. Many, if not most, are actually over sizing and creating excess headspace that way when none need exist. Over resizing is the major reason many "experts" suggest we only load our brass five times before tossing it. Sized correctly, my cases last three to five times that many loadings, sometimes more. And I mean fulll pressure rifle loads.

To properly adjust the FL sizer you need to accurately know the head to shoulder length of your fired cases. Use the Stoney Point tool to find that. Then, I believe it's simplier to back the sizer off a bit and work down toward the target length.

Put your sizer die in the press and adust it so it touches the raised shell holder. Then back the die out a quarter turn, that moving the die about 16 thousanths of an inch up. Size a case then measure it's head to shoulder length. It will likely be longer than it was before sizing. Adjust the die down about 1/16 of a turn, that being about 4.5 thousants, and test it again. Keep this up until you get the case shoulder where you want it, 2 thou below fired length is a good target. It won't be totally consistant because brass isn't that consistant an alloy so some cases will spring back at the shoulder a little more than others. Secure the die's lock ring to save the adustment.

Normal head space tolerance is about 8-9 thou, total range. If you move the die any more than 1/16 turn per adjustment you can cover more than the full range tolerance range quite easily. Go slow here.

A Wilson type case gage (a "go-no go" type gage, or "stop and go") has a chamber precisely cut into a solid cylinder of steel. The cylinder shows both ends of the case and has a small step cut at each end. The mouth end is a case length gage, we trim if the case is higher than the step. The other end is a headspace gage and the head should be between the two levels to make the case meet SAMMI specs.

SAMMI specs don't mean at thing to a competent hand loader working with his own rifle. The actual headspace length means nothing if a case properly fits the chamber in which it's fired. By adjusting your sizer as described above, your cases WILL fit your chamber, period. I no longer use my Wilson SAAMI case gages for anything except those rare occasions I load for someone else.
Reply With Quote
  #6  
Old 11-01-2008, 06:15 PM
Silver Member
 
Join Date: Jan 2005
Posts: 256
Re: adjusting head space

Boomtubes instructions are good. I'll add a couple of other tips...having used the same tool for a few years. Knock out the primer before taking your measurements...alot of times the primer can back out about .001 to .002 and goof up the measurements.
The second tip being that you will usually have to fire your virgin brass 2 times before they fully expand to the length of your chamber. Often one firing will leave them .001-.003 shy of full expansion.
Reply With Quote
  #7  
Old 11-01-2008, 11:04 PM
Platinum Member
 
Join Date: Dec 2002
Location: Northern Michigan
Posts: 1,014
Re: adjusting head space

Quote:
Knock out the primer before taking your measurements...alot of times the primer can back out about .001 to .002 and goof up the measurements.
This is good advice.

Quote:
The second tip being that you will usually have to fire your virgin brass 2 times before they fully expand to the length of your chamber.
This is also good advise but I'm on my 3rd & 4th firing of 338 Edge brass and have yet to bump a shoulder. So unless you can feel that things are tight when you drop the bolt I wouldn't worry about bumping the shoulder back. Though it may grow a little when you FL size without bumping the shoulder. It doesn't hurt to double check.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: adjusting head space
Thread Thread Starter Forum Replies Last Post
300 WSM Head Space? Rickyrebar Reloading 10 02-26-2013 10:17 AM
Head space ??? feelinducky Reloading 5 08-23-2011 08:35 AM
Head space issues!!! winmag Reloading 9 05-01-2010 04:13 PM
head space foreign The Basics, Starting Out 3 08-09-2008 08:03 AM
7mm rum head space gage ramp Reloading 2 03-01-2007 09:34 AM

Current Poll
Do you plan to buy a new custom rifle in the next 12 months?
YES - Of course - 72.92%
1,648 Vote
NO - wife/girlfriend won't let me. - 27.08%
612 Votes
Total Votes: 2,260
You may not vote on this poll.

All times are GMT -5. The time now is 09:16 AM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC