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Live Oak
01-20-2010, 10:39 AM
I'm sure it has been asked before, when using a case to adjust head space do you use a new case or a new SIZED case or does it make any difference ? I'm sure I'll get reply's saying to use the gauge's, but .......... everyone is different.


possum1,

I have been considering going to a 22-250 Ackley Improved for the next barrel on my Model 12 VLP. Getting an understanding of the steps involved and setting of headspace is something that I am a bit fuzzy on .

possum1
01-20-2010, 10:01 PM
OK feller's, I've got a house full of kid's so I'm used to trying to make everyone happy. The brown truck came today with all my part's so I got me a set of gages. Going to try it both way's just to see which work's best for me. Thank's Live Oak for the link's to the video helped alot !! So wish me luck, going to work on a Savage ;D

possum1
01-20-2010, 11:58 PM
Wouldn't it be a great time to have a new stock ;D

Live Oak
01-21-2010, 12:00 PM
OK feller's, I've got a house full of kid's so I'm used to trying to make everyone happy. The brown truck came today with all my part's so I got me a set of gages. Going to try it both way's just to see which work's best for me. Thank's Live Oak for the link's to the video helped alot !! So wish me luck, going to work on a Savage ;D


Very welcome. Be sure to post your results. I am considering doing the same thing but installing a 22-250 Ackely Improved barrel on my Model 12 VLP

possum1
01-21-2010, 05:30 PM
I said I was going to try both, gage and case, but just used the gage. Found a post SharpShooter had written and used the go-gage, tightened it up on the go-gage; then put one peice of tape on the go-gage and tried the bolt like, he said wouldn't go, got .002. After I fire the cases I'll see if I can get more, from what I read and hear less the better. Shooting like a charm at 100yds sometimes the hole just get's bigger ;D Got me a cheap custom 200 ;) Almost forgot, don't know if it's relavent or not. When I was talking to Jim at NSS about the barrel I mentioned purchasing gun vise and barrel blocks he told me all you need is Wheeler action wrench and the barrel wrench, he was right, put the barreled action on the basement floor one good small rap at it broke loose, well worth the $46 bucks.

MikeCTX
01-21-2010, 08:15 PM
Same way I did mine, including using the gauges and tape. One hint, don't do what I did last weekend - had some loads that were showing me pressure signs (bright marks and tight bolt - found the issue) but was afraid I might not have gotten the headspace correct so tried the go gauge again - good idea, but I had forgot to take the tape off and when the go gauge would not close, figured I had messed up and took the rifle apart and re-head spaced it again. Then found the tape....good practice but gave me a little fright at first.

BTW - problem was dumb one, had just a bit of Imperial wax from sizing on a few cases, it seems to be what caused the issue. The cases in question all felt 'wet' after firing and seem to have a film on them when I resized them. Like I said dumb mistake and I was lucky. Lessons learned the hard way make a BIG impression.

possum1
01-22-2010, 03:41 AM
Bet it was easier to get apart the second time ;) or was it a factory assembly ?

319
01-22-2010, 11:01 AM
I finally put my first Savage together last night. 6.5X284 on a Mod 12 action. I watched the vids(Thanks for posting those links!) and every thing went very well. The tape worked like a charm. I wouldn't have believed it would keep the bolt from closing unless I had seen it!! Now I have to suffer through waiting for brass and dies. Soon the Mod 12 will be a 260(when McGowen trades me 1:8 I ordered for the 1:9 they sent!) and the 6.5 will be on a Mod 112 in a Joel Russo stock that he did for me last year. I can't wait to get out shooting!

Pete K.
01-22-2010, 06:10 PM
Hey Ace,

Does that avatar of yours look just like you?



If Ace says "yup" then I have a dog for him...

http://img.photobucket.com/albums/v64/pdexter46/TNBIRDDOG2.jpg

Just funnin' you Ace and no harm intended. But seriously... about your avatar..???

Pete ;D

Dirk
01-22-2010, 06:46 PM
Good one Pete! ;D

~Ace~
01-22-2010, 06:57 PM
NOT Cool to be postin a mans Dawgs without Askin !

possum1
01-22-2010, 07:59 PM
That just aint right ;D

bigedp51
01-22-2010, 08:55 PM
After reading this posting I would like to add a few facts, the average American new unfired cartridge case is approximately .002 (two thousandths) shorter than minimum head space for a given caliber.

A fired case that has been full length resized “should” be under minimum head space BUT this depends on the accuracy of your shell holder dimensions, the accuracy of your resizing die and “how” the die is set up in the shell holder.

How do I know this, I have been reloading for over 40 years and I have gauges to check the length or cartridge head space.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP5130-1.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP4394.jpg

Knowing that a new unfired case is approximately .002 shorter than minimum head space and “if” you have a set of vernier calipers you could use an unfired case to setup your barrel for proper head space.

Step 1. Take the case you plan to use and measure the case length with your vernier calipers and write the measurement down.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP0710.jpg

Step 2. Take a fired spent primer and partially start the primer in the primer pocket.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP0704.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP0706.jpg

Chamber the case, eject and re-measure the case length, you want this measurement to be approximately .004 to .005 larger than your first case measument. What you are striving for is a head gap clearance or air gap between .002 and .003 thousandths at the rear of the case and the bolt face.

Below, an example of excessive “head gap clearance” or the “air gap between the rear of the case and the bolt face on a .303 British Enfield.

http://i122.photobucket.com/albums/o254/bigedp51/9-2.jpg

I reload and prefer tight head space because it helps prevent stretching and thinning in the case web area of the case and helps promotes accuracy, BUT sometimes the word head space means nothing.

http://i122.photobucket.com/albums/o254/bigedp51/image006e.jpg

http://i122.photobucket.com/albums/o254/bigedp51/762natoin3006.jpg

possum1
01-22-2010, 09:16 PM
I reload and prefer tight head space because it helps prevent stretching and thinning in the case web area of the case and helps promotes accuracy, BUT sometimes the word head space means nothing.

Is it feasible or SAFE to try and get .000 head space ? May be a dumb question I don't know, but I am a stickler for PERFECTION ;)

bigedp51
01-23-2010, 02:30 AM
I have one Stevens 200 which I was contemplating replacing the barrel on and why I joined this forum and 12 military Lee Enfield .303 rifles. On the Enfield's which I have experimented on with setting the the head space from -.003 to + .020 or three thousandths under minimum head space to twenty thousandths over zero head space.

Military head space settings for the Enfield rifle are .064 min to .074 max, commercial American SAAMI head space is .064 min to .067 max and .071 field max.

Now to your question “Is it feasible or SAFE to try and get .000 head space ?” It is possible BUT safe depends on your definition of safe. It is perfectly safe to have .000 (zero) head space sitting at the shooting bench shooting small holes in paper targets. On the other hand it is very stupid and dangerous to have .000 (zero) head space on a rifle you are hunting Cape Buffalo with.

You actually set .000 (zero) head space when you fire form your cases and neck size only, when you full length resize you want the cases approximately .002 smaller than chamber head space to ensure chambering in hunting conditions.

On a military British Enfield with the head space set at the maximum of .074 and with a cartridge rim thickness of .058 you have a head gap clearance or air gap of .016. This overly large head space setting is to ensure the cartridge chambers under combat conditions.

At .000 (zero) head space with neck sized cases and shooting my Enfield at the range in subzero weather, cold cartridges and a warm chamber were causing condensation. The condensation droplets froze and prevented the case from chambering.

So yes you can set your rifle at .000 head space BUT variations in case manufacture (length), dirt and debris and weather may prevent you from chambering your cartridge.

On the Enfield rifle some long range rifles were accurized in the UK by Fultons of Bisley with the bolt “kissing” the rear of the case, BUT each case was checked with a rim thickness gauge to ensure chambering.

Head space comes in three flavors, tight on target and bench rest rifles, medium on hunting rifles and large on military rifles. With the adjustability of setting the Savage/Stevens rifles head space you can set your own “sweet spot” where you want to............................................

The trick is making sure your cartridge cases chamber under the conditions you are shooting and just as important to reloaders is that the case is not stretched and warped on firing.

With the rimed .303 British case I can cheat the word “head space” with a rubber o-ring that holds the case against the bolt face when fire forming and then neck size only thereafter.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6290.jpg

Below is what happens to your cases when fired in a chamber with “long” head space.

http://i122.photobucket.com/albums/o254/bigedp51/headspacestretch-1.gif

By using the o-ring method of fire forming your .303 cases you are setting a “zero” head space condition and this prevents case stretching on older rifles where the head space can no longer be adjusted.

http://i122.photobucket.com/albums/o254/bigedp51/headspacestretch_frame_0001.jpg

After fire forming these cases they will head space on the shoulder and not the rim and by neck sizing only you will have .000 or zero head space. (I just don't use these cases to hunt Cape Buffalo)

http://i122.photobucket.com/albums/o254/bigedp51/fireformed-zeroheadspace.jpg

The funny part in this head space discussion here is that in an Enfield forum you would be burned at the stake for talking about setting your head space to “zero head space” by the collector purests who say “.074 is good enough for me” (.016 head gap clearance) ::)

possum1
01-23-2010, 04:23 PM
very very interesting. When the head space is tight ( when other things aren't contributing ) the bolt will close tight or with some force ? correct ??

lineman69
03-01-2010, 09:02 PM
i have been reading this for a while and still a little leary about setting this barrel myself.my situation is this i have a redding indicator die for a 6.5 x 284 after measuring the headspace gauge and a new unfired case i find the headspace gauge to 4 thou. bigger so wich should i use to set this barrel?

possum1
03-02-2010, 02:46 AM
Sound's like to make you comfortable use the gauge. A fired case would be better, like they told me you can alway's redo to the fired case. I was very uncertain about doing it myself. It seem's easier to me than changing my auto oil and I call myself a mechanic ;)

~Ace~
03-03-2010, 01:09 AM
"Headspace" is a happy medium that should allow most all Factory and in spec handloads to chamber.... and if you plan to shoot Factory Ammo, setting it loose with a gauge is fine. If you want the Most out of your rifle, and you reload.... Setting the HS off a FIRED and Resized In Your Die case is the way to do it. Your setting it to YOUR specs. Accuracy is sure to be helped at lease some, Brass life is Really helped.

axaviere
03-06-2010, 06:20 PM
anyone have this happen? i got the headspace set, put the barrel in the blocks and started to tighten the nut and the nut, lug and receiver turned. i had to take it apart, reset the headspace and try and figure if clamping the receiver would be better when i retighten it all... anyone?