Savage 110, 7mm rem. Mag rebarrel headspace question???

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DelawareDave

Inactive
So I have a mid 80's Savage 110, 7mm Remington Mag. Recently rebarreled it with an e.s shaw ss mag barrel. When I installed the new barrel I checked the headspace multiple times as I was resembling the rifle. Tightened the barrel nut down pretty darn tight and go guage locked down. Torquing barrel down, checked "go" and "no-go" gauge all was good. Put stock back on and put rifle away. Next morning, went to test fire and figured I would run the head space gauges again, well to my surprise when I tried the "go" gauge, the bolt would almost completely close but wouldn't lock down... Tried to cycle a few rounds with out firing and they locked down with no resistance, and when I extracted the cases no signs of dents, creases, etc... Fired a few rounds and brass looked and measure normal... Should I be concerned??? Do I need to disassemble and retorque barrel down or should all be good??? Any help would be great! Also after firing about 10 round "go" gauge is still doing same thing (close almost all the way but wont lock bolt.
 
It depends on how paranoid you are.
But it sounds like it's one of those temporary anomalies we hear about.
It might have just been that one case being slightly off, too.
With the checks you've done, personally I wouldn't sweat it.
But then, I'm not the one shooting it, either.
Oops, almost missed that last sentence of yours.
Hmm.
Not sure, now.
Brings us back to my first sentence.
Brass not all identical?
Head space just on the edge?
 
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Did you remove extractor and ejector (plunger type) before using the go gauge? May make a difference? If bolt will not lock down on a go gauge, ammo may not chamber. Head space is on the belt, but the head to datum of ammo must fit the chamber also. You seem to be ok now, but new brass may not chamber? My guess, not a gunsmith.
 
DelawareDave, it is either, or but not both for most smiths and reloaders. I am the exception. I think nothing of cutting and or grinding the belt off of the a magnmum case to determine the length of the chamber from the shoulder to the bolt face.

And then when it gets to removing all of the parts I deal with that also, If the extractor is in the way I cut a notch in the rim of the case. And then there are control feed and push feed. A few reloaders have a problem with push feed systems. On a push feed system the extractor must jump the rim of the case; sounds simple but if the extractor is removed and everything seems to run smooth 'and then' the extractor is installed there is a remote chance the case will not allow the bolt to close.


F. Guffey
 
So to clarify just a bit, the head space gauge I used is the one that came with the barrel kit, it head spaces just off the belted rim. All the brass I put in it chambers and locks good, but the "Go" gauge wont close anymore. The bolt handle goes almost all the way down but just wont lock with the "go" gauge....
 
Probably nothing to worry about but... There is always the potential that it could shorten or end a range session if you are unable to chamber a round...

The " Go " is supposed to go ! ( with very light effort ).
 
Just a thought, check the length of your front stock screw, it may be protruding into bolt race now that the barrel contour maybe somewhat different.....
 
You never stated whether you're handloading for this- or using factory ammo.
Big difference when it comes to belted magnums from what I've been told (don't own one...).

First firing is basically a fire-form. Factory ammo is designed to headspace off the belt.

If you're handloading for this- do some research. Most guys headspace off the fired brass (shoulder). Setting headspace off the belt usually results in much shorter brass life and case head separations.

If you're just shooting factory- and the same brand/load- it doesn't make much difference as long as the drag isn't excessive (light drag on a belted magnum should be fine, perhaps even preferable) and you're not having issues with hard extraction.

If you're reloading for this, suggest a search or maybe a new thread on the Reloading section to get input from those that do it..
 
You will have no safety or danger issues with a tight headspace from a bolt gun... it is too loose of a headspace, or too tight of a headspace in a semi-auto that can fire out of battery, which presents a potential danger. The only issue you may have is some factory ammo MAY not chamber. If you reload or know for a fact that you will stick with one brand of factory ammo, you are good to go with what you have. Loosening the headspace a touch (like probably .003 or so) from where you are now will make it a little more reliable with a variety of ammo.

FWIW, many like a tighter headspace because it is LIKELY (not promised) to be slightly more accurate. If you shoot only your reloads, headspace doesn't even matter so much as you can adjust the brass to the chamber instead of adjusting the chamber to the brass.

Short answer, you shouldn't have a safety issue. Only a Potential reliability issue as some factory ammo may not chamber, or chamber hard.
 
So to clarify just a bit, the head space gauge I used is the one that came with the barrel kit, it head spaces just off the belted rim. All the brass I put in it chambers and locks good, but the "Go" gauge wont close anymore. The bolt handle goes almost all the way down but just wont lock with the "go" gauge....
Click to expand...

Understood: But when securing the barrel with the lock nut there is a chance the barrel will be pulled forward when the slack is removed between the threads on the barrel and receiver. It is not likely anyone here is going to measure the difference between a minimum length case and a head space gage. I have and I do measure the difference; the difference when comparing a go gage to a minimum length 30/06 case I find the difference is .005". AND I am not talking about the length having anything to do with a case from the mouth of the case to the case head.

F. Guffey
 
And then there are those that use cases with a know distance from the belt to the case head. When adjusting the barrel before securing the lock nut they check their work by removing all of the clearance on a new case and then using a feeler gage to adjust the barrel out .005". And then there are those that spend too much time talking about their tight chambers.

F. Guffey
 
I fail to grasp the relevance of belted magnums "today".
Designed for cases with shallow shoulder angles- when it seems that in many cases a steeper shoulder angle (aka Ackley Imp.) produces better performance- and allows the case to headspace off the shoulder.

Headspacing off a belt- while at the same time expecting extremely tight shoulder clearances for case life seems to be an unnecessary tightrope walk with more modern, beltless magnum chamberings available.

Some (like the 7mm Rem) are still popular- so I must be missing something.

:confused:
 
I fail to grasp the relevance of belted magnums "today".
Designed for cases with shallow shoulder angles- when it seems that in many cases a steeper shoulder angle (aka Ackley Imp.) produces better performance- and allows the case to headspace off the shoulder.
Click to expand...

I was under the impression that it had much more to do with offering more support for the web of the brass without sacrificing case volume for the higher pressures. I did not even realize it had to do with headspacing off the shoulder, nor do I see where headspacing off the shoulder would be an issue as it has more shoulder angle than both a 308 and 30-06 round... both of which headspace from the shoulder.
 
^^

My point was that it's trying to accomplish two areas of tight tolerance at the same time- sorta like re-barreling a Mauser and hitting the inner torque ring at the same time as the receiver ring when the barrel is torqued into place.

Maintaining minimal headspace- while at the same time accomplishing no more than a thou or so of shoulder clearance seems like an unnecessarily tight-wire act for reloaders. For factory ammo shooters, they could care less if the case stretches a bit at the belt, or blows out at the shoulder. But for reloaders it seems it be far more critical for case life.

I have not re-barreled one as yet, but I suppose that day will come.
 
All the brass I put in it chambers and locks good, but the "Go" gauge wont close anymore.
Click to expand...

So, do you want to shoot the gauge?

I would leave it as is. One day you might get brass with a maximum belt and have to reset the barrel. One day.
 
My point was that it's trying to accomplish two areas of tight tolerance at the same time- sorta like re-barreling a Mauser and hitting the inner torque ring at the same time as the receiver ring when the barrel is torqued into place.
Click to expand...

"My point was that it's trying to accomplish two areas of tight tolerance at the same time-" Not my fault that seems difficult. Before I screw the barrel into the receiver I make sure the barrel seats first on the 'C' ring first then I measure the gap between the receiver and shoulder at the end of the threads. No gap means I have to determine if both seated at the same time etc. etc. Then there is that method/techniques used from the beginning; Lay the barrel out on the right and the receiver on the left. measure the barrel shank and thread length then measure from the front of the receiver to the 'C' ring and to the bolt face.

I checked a 257 Weatherby VZ24, the face of the barrel was gas cut meaning it was torqued to the front of the receiver and shoulder at the end of the barrel threads. The rifle was one of the most accurate rifles I had ever seen. And then one of those 'and then' moments. A couple of smiths claimed they stuck a jag in the rifle while cleaning. They lied; the barrel has a broken jag, bullet and a .250" drill broken off in the barrel.

F. Guffey
 
"My point was that it's trying to accomplish two areas of tight tolerance at the same time-" Not my fault that seems difficult.
Click to expand...

So you miss my point (again) in that belted magnums seem to be "outdated" by newer and more efficient beltless magnums- just like the inner torque ring on a Mauser.

Much better to true the receiver face on a Mauser- than to crush fit the barrel.

Methods, designs, and materials evolve over time.
 
So you miss my point (again)
Click to expand...

Again? Again, this stuff does not lock me up nor does it drive me to the curb.

Don't have a head space gage? Not a problem. If a reloader/smith does not have a no go-gage, that should not be a problem. If a reloader/smith has a field reject gage and no go gage or no go-gage; that is not a problem for me. I can use a go-gage, I can use a no-go gage or I can use a field reject length, that would be one or the other or either; again this stuff does not lock me up.

Again, I have no problem cutting and or grinding the belt off of a belted case when determining the length of the chamber from the shoulder of the chamber to the bolt face.

And then there was that time during the big inning. I was not there but H&H designed a chamber to use cases with belts in about 1905 +/- a few months. The purpose of the belt was to hold the case to the tear when fired. They had little interest in what happened to the case ahead of the belt; basically they wanted the case to seal the chamber.

It is and was not me that got all giggly over the collet die that sizes the case in front of the belt. I have upset a few cases with heavy case heads and bulges in front of the belt, I have found belted cases that have been hammered with heavy loads. Again, this stuff does not drive me to the curb. hammering case heads with heavy loads is a bad habit.

F. Guffey
 
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