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Headspace questions galore!

OK, Gents. It's time to call in the pros. A buddy of mine who's a lefty was given an old LH savage rifle with the proviso that it needed work. He was told it had exessive headspace. He's asked me to get it up and running, but $$ are seriously limited. My first thought was a quick re-barrel (The existing barrel has sights, so it wouldn't set back as simply as most Savages) then I started looking it over, and I'm not sure there is really any problem. I don't have chamber gauges for a 264 Win Mag, but I used a new Win case, and a once fired case resized in my dies, with a strip of plasti-gauge on the case head to measure the "gap," and got .012" and .010" respectively. .012" is certainly more than I'd chamber a new barrel with, but it doesn't sound the least bit dangerous.

What am I missing?
 
Did the PO say the gun wouldn't shoot?

Have you tried putting a couple of rounds through it to see how it does?
 
Not yet. It will be a while before I can fire it in the "lashed down with long lanyard attached" mode. ;D That's obviously next if no-one has a better suggestion. I was just hoping someone could "kick a hole in that logic." I really think it's OK as is, but my early years were spent as a machinist, not a 'smith. I'm hoping someone has an idea I didn't think of. The problem may well be in the neck area, which I can't measure without casting.

I hearby absolve anyone who replies of any liability, expressed or implied. I'm simply looking for ideas I may have missed. It's a $200 rifle, but I'd hate to blow it up on a bench tet for lack of creative thinking! I'm a better than average mechanic, but I know there are much better 'smiths than me out there.

Please help if you can
 
The difference in a belted magnum between "Go" and "No Go" is 0.003. By your measurments the gun is chambered 0.009 to deep. Primers will back out and the case will streach/separate just ahead of the belt
LJPeter
 
Seat bullets out far enough to "jam" them into rifling and that will keep the case head tight to the bolt face. Then just fire form like you would with an Ackley cartridge! Not the end of the world. People fire form a 6br to a BRX which is .100 longer body ;)

Dan
 
dantiff2 said:
Seat bullets out far enough to "jam" them into rifling and that will keep the case head tight to the bolt face. Then just fire form like you would with an Ackley cartridge! Not the end of the world. People fire form a 6br to a BRX which is .100 longer body ;)

Dan

Actually, on an Ackley chambering, the headspace is set a few thousandths short of the parent case, ie. a false shoulder. Most folks form a false shoulder of some kind with any "improved" case(such as 6br to 6brx or 30-06 to 30 Gibbs). It is the safest way to fireform to the improved version of most anything.

To the OP, if your saying that the headspace clearance of this rifle is .012", then the rifle is very dangerous if fired in its current condition.
 
willsnipe said:
OK, Gents. It's time to call in the pros. A buddy of mine who's a lefty was given an old LH savage rifle with the proviso that it needed work. He was told it had exessive headspace. He's asked me to get it up and running, but $$ are seriously limited. My first thought was a quick re-barrel (The existing barrel has sights, so it wouldn't set back as simply as most Savages) then I started looking it over, and I'm not sure there is really any problem. I don't have chamber gauges for a 264 Win Mag, but I used a new Win case, and a once fired case resized in my dies, with a strip of plasti-gauge on the case head to measure the "gap," and got .012" and .010" respectively. .012" is certainly more than I'd chamber a new barrel with, but it doesn't sound the least bit dangerous.

What am I missing?

In Europe the CIP has a tolerance of 0,1mm for the headspace (0,004"). The headspace must be within this tolerance of the gun won`t get the proof stamp and can`t be used.
In my experience this tolerance is to high because the cartridge brass has much more tolerances...
0,2mm (0,008") won`t make trouble.
When the headspace between case and bolt face is higher than 0,3mm = 0,012" it starts to show you overpressure signs - but there is no overpressure. Only the primer is coming out and is then compressed.
Too high headspace does not have a big effect on the accuracy.

Funny story: my father has a Mauser 98 in 7x64 from the 60`th with official proof marks. The headspace on this rifles is 1mm (0,04") deeper and it works since many decates and shoots great. I measure the chamber last year because he get some trouble with hard RWS brass that cracks. Now he has fireformed a lot of cases and now they are only neck sized.
 
.012 is a bunch when it comes to rifle chambers. You are using the 2 most unreliable sources to check headspace IMO. A new unfired case can be .005+ shorter than a go guage or even a FL sized case. Full length sized cases can vary several thousandths from one die set or different brands of dies. They are NOT held to the same precise tolerances that proper guages are.

I cut my chambers to go + .001ish. Full length sized then leaves me a couple thousandths as I near always FL size for personal reasons. However I have them tight enough that brass isn't worked as hard as firing/FL sizing reloads in a factory chamber.

For peace of mind and safety you really need to round up at least a no go guage.

Just my .02 cents worth.

Respectfully,
Dennis
 
+++ on every statement that .012 is too much as it is. Unscrew the barrel & re-set the headspace. Period. BELIEVE me that you don't want to see a case/head separation. Things come apart violently. This isn't an Ackley issue.
 
Unscrew the barrel and reset the headspace. I make a "go gage" that is .002 longer than a resized case by placing a piece of scotch tape on the base of a resized case. (Scotch tape is .002 thick) Trim it so so tape does not protrude over the rim. I've set the headspace on my Savage dozens of times this way. Now, when you resize, you will only set the shoulder back .002. No overworking the brass.

Use this method this ONLY if you will be using your own reloaded ammo exclusively as you effectively have a "custom" chamber.
 
I regularly load with new brass and measure head space on everything just because I can. I can assure you there is nothing wrong with .012" head space and as long as the bullet is jammed into the rifling or like was said "a false shoulder is made", you'll be good to go.
The last batch of WIN brass I loaded for my 223 rem had .007-.008 thousandths head space right outta the bag compared to my fired rounds out of my Remington. I've read plenty of people loading for a 6 BRX that said they just jam the bullets, (no false shoulder) and use a moderate powder load and the fire form load shoots almost as good as the formed load . That's ".100" longer body taper and the brass flows to fill the chamber. Make sure the head is tight against the bolt face so the firing pin can reach the primer.The shoulder will move forward with little resistance.
I've personally shot Military 8mm Mauser rounds out of my K98 with .010-.012 thou head space. You cannot jam the bullet into the rifling on that old gun. I don't have any problems. Never had a case head seperate... ;)
 
1+ for what danniff2 said. If it is new brass and you don't fully resize to sammi specs ( set your die to a once fired case from that gun ) once formed to your chamber your good to go. Just don't shoot factory ammo.
 
Generally brand new brass is slightly smaller than SAAMI specs. I run mine through a sizer die and it NEVER touches the shoulder. I do it mostly to "iron" out the necks. Like I said "brand new brass or ammo will be smaller". Don't use this as a head space measurement. You need a "go" gage and the ability to measure to the datum point on the shoulder .
 
Determine Correct Headspace

With the exception of the .240 Weatherby Magnum, most belted, magnum cartridges are based on the .375 H&H Magnum case. Therefore, they all use the same headspace gauges. The following is a partial listing of those cartridges which use the same Belted Magnum Headspace Gauges: .257 Weatherby Mag., 6.5 Rem. Mag., .264 Win. Mag., .270 Weatherby Mag., 7mm Rem. Mag., 7mm Weatherby Mag., 7mm STW, .300 H&H Mag., .300 Weatherby Mag., .300 Win. Mag., .30-.338 Win. Mag., .308 Norma Mag., 8mm Rem., .338 Win. Mag., .340 Weatherby Mag., .350 Rem. Mag., .358 Norma Mag., .375 H&H Mag., .416 Rem. Mag., .458 Win. Mag.

A go-gauge is used for a new install
A no-go-gauge is used to check wear on a used gun if so what is worn & is it safe to shoot
A field-gauge is the extreme end of wear not safe to shoot
 
dantiff2 said:
I regularly load with new brass and measure head space on everything just because I can. I can assure you there is nothing wrong with .012" head space and as long as the bullet is jammed into the rifling or like was said "a false shoulder is made", you'll be good to go.
The last batch of WIN brass I loaded for my 223 rem had .007-.008 thousandths head space right outta the bag compared to my fired rounds out of my Remington. I've read plenty of people loading for a 6 BRX that said they just jam the bullets, (no false shoulder) and use a moderate powder load and the fire form load shoots almost as good as the formed load . That's ".100" longer body taper and the brass flows to fill the chamber. Make sure the head is tight against the bolt face so the firing pin can reach the primer.The shoulder will move forward with little resistance.
I've personally shot Military 8mm Mauser rounds out of my K98 with .010-.012 thou head space. You cannot jam the bullet into the rifling on that old gun. I don't have any problems. Never had a case head seperate... ;)

Just because you haven't blown yourself up doesn't make what you are advising safe. In fact, excessive headpace comes at .005". Thats why sammi go and no-go guages are .004" apart
 
With a belted round it head spaces off the belt and bolt face. If thats within .003", ok.

Could be your chamber length from the forward part of the belt to the datum on the shoulder is a little long and the brass should fire form to it. Just don't bump the shoulder after fire forming.

I just got into this this with my buddies rifle which is an 7mm STW.
 
Since it has sights and you're on a budget, I'd neck up new or freshly annealed 264 brass to 7mm, and then neck them back down to 264 leaving a crush fit on a false shoulder, and fireform to fit. Safe, cheap, and effective.
 
alf,
I'd buy new 7mmRem brass and run it through the FL sizer creating a false shoulder. ;D

Belt dimensions are notoriously sloppy, occasionally to the point where the headspace guages can be totally worthless.
Cheers...
Con
 

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