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darwins
January 15, 2011, 03:52 PM
4 years ago I bought a German Mauser on impulse. I kind of took a risk on what I though might be a WW1 rifle that was reworked to Kar98k specs. I also bought it to be a shooter. However, since then, for various reasons I have come to the conclusion it isn't what I thought it was and, even worse, it isn't a shooter. The bolt closes on a no-go head-space gauge. So, I've been debating what to do with it. I can't feel good about selling the rifle to somebody without revealing to them that there is excessive headspace. The way I see it I have two options:
1) Have a gunsmith screw the barrel in a tad further to fix the headspace problem. This will shift the sights to the left a bit. In order to fix that, he will have to sweat the sights off, align them correctly, re-fix them in place and then re-blue the sights and barrel. Correct?
2) Part the gun out. Unscrew the barrel from the receiver and then sell the receiver and action, stock and metal parts and barrel separately.

Ultimately, the goal is to recoup as much of the $195 that I spent for the gun as soon as possible. Are there other options I haven't considered? Any advice?

Thanks,
Darwin

jaguarxk120
January 15, 2011, 04:32 PM
I'm assuming the rifle is a 8mmx57, so why not have it rechambered to 8mm-06 a very easy rechambering job. Now you have a 8mm wildcat that was very popular right after WWII. The GI's that brought back the Mauser 98's soon found out that 8x57 wasn't loaded in great quanity's here, but 30-06 brass could be had by the bushel. Just about every die maker will or has dies for the 8-06 and it will perform very well, lots of loading data for it, just look.

jimbob86
January 15, 2011, 04:50 PM
1) Have a gunsmith screw the barrel in a tad further to fix the headspace problem. This will shift the sights to the left a bit. In order to fix that, he will have to sweat the sights off, align them correctly, re-fix them in place and then re-blue the sights and barrel.

Your smith can't screw the barrel in a full turn (sights back to 12 o'clock) and ream the chamber?

I had a smith do that with a Bubba'd 1892 manufactured Gew. 88 Commision rifle that had a headspace issue (mismatched bolt ... bolt from another 88). Cost me $150, and it's still a Bubba'd Gew. 88 ...... but it works for what it is.

Unclenick
January 15, 2011, 04:59 PM
Since the NO-GO gauge is swallowed, and if you don't know its history, you also might want to do a chamber casting and see if it is, for sure, chambered as labeled and not already wild-catted. Lot's of shade tree gunsmiths have altered a chambering without impressing or engraving the change onto the barrel.

jimbob86
January 15, 2011, 05:19 PM
Lot's of shade tree gunsmiths have altered a chambering without impressing or engraving the change onto the barrel

..... and even more handloaders hot rodding aging old milsurps..... just to see what it will do....... stretching recievers happens.....

Jim Watson
January 15, 2011, 05:24 PM
Tell me how you closed the bolt on the No-Go gauge.

Did you load it in the gun like a cartridge you were in a hurry to fire?

Did you strip the bolt to get the mainspring out of the way and close the bolt over the gauge with pinkie pressure?

GunCat
January 15, 2011, 05:31 PM
...and after closing on the No-Go gauge would the bolt also close on a Field gauge?

Pathfinder45
January 15, 2011, 06:51 PM
You might try using headspace gauges for .30-'06. If it was already rechambered to 8mm-'06, that would likely be the quickest way to reveal it. A chamber casting would probably be the surest way of finding out.

mapsjanhere
January 15, 2011, 07:45 PM
One more option to check is the 8x60. After WWI, 8x57 was a restricted caliber according to the Versailles treaty, and some guns got reworked as "civilian" 8x60.
But if it's a 8x57 resetting the barrel one turn and reaming the chamber shouldn't be too bad.

darwins
January 15, 2011, 08:23 PM
Thanks for all the great replies. It is still otherwise in military configuration and if it hasn't already been reamed out ti a wildcat caliber maybe turning it a full turn and reaming it out might be the way to go. I'll have to look around and see what the costs will be.

I don't have a field gauge so I haven't tried that. I didn't fully disassemble the bolt because getting that blasted extractor off is a pain in the butt but I did try it without the mainspring. I placed the rim of the headspace gauge under the extractor and then slid the bolt and headspace gauge into place. I do feel a bit of resistance just before the bolt closes completely.

jaguarxk120
January 15, 2011, 08:30 PM
Rotate the extractor till it is out of the retaining grouve. Then push forward and it will pop right off.

James K
January 15, 2011, 11:56 PM
Once more, repeat after me: closing on a NO-GO gauge does NOT indicate excessive headspace.

I don't care what some so-called "expert" said, closing on a NO-GO gauge does NOT indicate excessive headspace. Repeat....

If the bolt closes on a FIELD gauge, the rifle MIGHT have excess headspace or be on its way to same.

Setting the barrel back a turn on a military rifle usually wrecks any collector value since things get all out of whack.

Jim

HankC1
January 16, 2011, 08:13 AM
Rotate the extractor till it is out of the retaining grouve. Then push forward and it will pop right off.
The fun part is putting the extractor back in. 98 mauser is not so easy to do. I would not mess with the extractor on a large ring mauser unless I have to. I slip head space gauges thru the extractor and guide into the chamber. Right or wrong, it is good enough for me.

mapsjanhere
January 17, 2011, 12:27 PM
Setting the barrel back a turn on a military rifle usually wrecks any collector value since things get all out of whack.
I was going by the "shooter" comment in the OP. If there's any collector's value left (for example the mod from Gew 98 to Kar98k is documented by the correct proof and repair marks) than sure do a full check first.

F. Guffey
January 17, 2011, 03:38 PM
It is not going to happen but: Let us pretend I am you for a minute or two, if I did not know what the rifle was chambered in, 8mm57 or 8/06, I would chamber a 270 round and then attempt to close the bolt, if the bolt closed I would know the chamber was as long as a 30/06. 270 W, 25/06 and the 8mm06 chamber fro,m the face of the bolt to the shoulder of the chamber. If I did not have a head space gage as in no, go and beyond I would use a 280 Remington case (caution) that would require keeping up with two things at once. AND when someone tells me I must remove the extractor to check head space, I smile, nod my head approvingly and walk away, If they ask me why I do not agree I will show them a head space gage that started that rumor, the gage does not have an extractor groove.

F. Guffey

and head space can be checked in thousands with a field gage.

Pathfinder45
January 19, 2011, 04:42 AM
What F. Guffey said. The light bulb came on.

Unclenick
January 19, 2011, 11:31 AM
Hatcher wrote in some detail about the great case-compressing mechanical advantage that closing a bolt applies. He describes how easy it is to stretch a chamber several thousandths when closing a bolt on a steel gauge.

People often think a NO-GO gauge is supposed to prevent the bolt from closing. Not so. The name is misleading. What is actually meant is the gauge should not find the end of a new chamber's headspace before the bolt closes. Not that the bolt can't close on it. That is why Jim Watson asked about your technique.

A FIELD NO-GO (usually just called FIELD) gauge serves the same purpose as a NO-GO gauge, except it is for used chambers. When a gun is used, the chamber gets smoother and burrs burnish and bolt lug surfaces burnish and the barrel threads settle, and all that can move a chamber forward several thousandths. This is normal and expected, so the NO-GO gauge for new chambers has to be shorter than is actually acceptable headspace. It's the FIELD NO-GO gauge that has the actual maximum length. The FIELD NO-GO gauge should not find or kiss the end of the headspace determinate before the bolt closes in a used gun. Only if that happened would you truly have an indication of excess headspace.

Modern gauges usually have both an extractor groove and an ejector cutout for gun designs with a spring-loaded ejector in the bolt face. The idea is to let you check headspace without bolt disassembly, but I find how well that goes depends on the gun. If it is a cock-on-opening action with an extractor in a fixed position on the bolt face that rotates together with the bolt, you can often make this work. In a cock-on-closing gun or in one with a slipping extractor that can drag, like the Mauser, it may be difficult to distinguish feeling the gauge touch down from the drag by other parts. You have to close the gun on the empty chamber and have that feel light and free of resistance to know if you can get away without stripping the bolt to use a steel headspace gauge.

So, if you felt any resistance whatsoever closing on a steel NO-GO gauge, you do not have excess headspace, but rather you have a chamber that is within new chamber dimensions.

One advantage to using brass cases as gauges, as Mr. Guffey does, is they flex instead of the steel, so you don't accidentally stretch the chamber to a significant degree. But you still need to have a good sense of feel and a good dose of common sense and understanding about what it is actually telling you.

darwins
January 19, 2011, 02:33 PM
I appreciate all the replies and feel better about the rifle now. I need to go check it again because I do remember some mild resistance prior to the bolt closing. The information in this thread is good and I now know more than before. Thanks all.

James K
January 19, 2011, 06:05 PM
Hi, Unclenick,

I don't like to argue with anyone's uncle, but headspace does not increase because the chamber "burnishes" or even that bolt lugs "burnish." It increases because high pressure slams the cartridge back against the bolt face and the bolt lugs in turn crash against the lug seats, distorting and compressing both the lugs and the lug seats.

Here's why. The chamber pressure of, say, a .30-'06, is around 50,000 pounds per square inch. The inside of the base of a case is about 1/10 of a square inch. When the rifle is fired, 1/10 of 50,000 pounds pressure pushes back on that case. And the pressure builds up in less than a millisecond after the primer fires.

To get an idea what it is like, imagine a rifle with its bolt closed standing with its barrel pointing straight up. In the barrel is a steel rod, resting on the bolt face. Welded to the top of that rod is a platform and every so often a Ford F150 Super Cab pickup truck (about 5000 pounds curb weight) is dropped on that platform. That is the kind of beating those lugs take, and what 50k psi means in terms of the impact on the rifle.

It is not surprising that rifles develop excess headspace; what is surprising is that they last as long as they do.

Jim

mega twin
January 20, 2011, 09:44 AM
I would definitly do a chamber cast.
The last 03a3 I had would not fire a 30-06 round.
Took it to a gunsmith to have the head space checked,and he found that it was chambered for a belted round,a .308 Norma.
I tied it to a tire and shot it twice with a looong string,and it stretched the action to where it had too much head space.
The rifle was not marked in any way to note a cartridge change.
Sad day with a cutting torch:(

F. Guffey
January 20, 2011, 10:19 AM
Mwga Twin, the rifle would not fire a 30/06 round, then it was decided the rifle was chambered to 308 Norma Mag? What was used in the chamber when you test fired the rifle? When did you test fire it, before you went to the smiths or after???

F. Guffey

mega twin
January 20, 2011, 02:50 PM
I took it to the smith ,after it would not fire the 30-06 round.
He determined that it was chambered for a belted magnum,and did a chamber cast to determine the chambering,and it was fired twice with that ammo,308 Norma Magnum,and the action stretched with those two firings,and then was destroyed.

F. Guffey
January 20, 2011, 03:44 PM
That is the way I read it but the 03A3 was not a receiver that was suspect and if head space was a problem the smith should have checked. When test firing the ammo should be new only unfired cases. As I have said I am not a fan of Hatcher but I do understand Unclenick's statement "wrote at length" he was talking to Springfield, Springfield built the 30/40 Krag with one locking lug because they could not build it with two locking lugs, THEN went on to build 800,000 ++ 03s that were suspect, Winchester /Browning found nickel steel in 1894 for the 30/30 M94, Springfield could not find Winchester or Browning just a few miles down the Interstate.

F. Guffey

Unclenick
January 21, 2011, 12:55 PM
Jim,

Lug setback was a serious omission from my post. I've seen (had) a number of rifles that changed headspace rather more in their early round life than they did later, so it seems they settled in. I suspect imperfect and sometimes slightly uneven lug contact when they were new had a fair amount to do with that, as none of these had lapped lugs in the beginning that I recall. I'm sort of watching my Steyr Scout's fired cases to see how well its chamber holds length. I'm curious if the precision grinding method used to fit the lugs does any better than average.

James K
January 21, 2011, 02:29 PM
Lugs do settle in. When Remington started with multi-lug bolts, there was a lot of gunzine gabble about problems if the lugs didn't bear evenly. A Remington engineer responded that "...of course they don't bear evenly as they come off the line. But we feed them a blue pill* and THEN the lugs bear evenly."

*A high pressure (75k psi in .30-'06) proof load, so-called because the cases are zinc plated for identification and have a bluish cast.

Jim

P.S. I can't imagine an '03 receiver stretching from firing two shots; the PSI pressure of the .308 Norma Magnum is no greater than that of the .30-'06, although there is a greater base area so the absolute pressure on the lugs is greater. Still, if an '03 receiver stretched like that, it was bad to begin with, possibly having been burned in a fire.

Jim

guncrank
January 21, 2011, 03:07 PM
I must be dumb but for the life of me, it seems to me that in gunsmith school we used two gauges when we where learning to chamber Mauser actions.
A go and nogo, that is all.
And I have continued to use those two gauges up till now.
Close on go and not close on nogo.
An stripped a bolt down completely.
CEW

mega twin
January 22, 2011, 07:27 AM
Jim,the rifle was a low numbered gun.
By whoever rechambered it,without marking it as to the change,there is no telling who did the work,or what shape it was in before the work was done.
An expensive lesson for me, but no one was hurt by it,except monetarily,so alls well.

F. Guffey
January 22, 2011, 05:00 PM
"The last 03a3 I had would not fire a 30-06 round"

The low number Springfield or Rock Island would just let go, nothing before and then all of a sudden the rifle would swarm, when loading for a low number I call it meets and or exceeds BUT that only makes sense to me, the ones that failed I attribute to sudden shock, if the receivers were able to stretch the failure would have been progressive and there is no way to add your low number to the list of known failures.

F. Guffey

Unclenick
January 23, 2011, 11:00 PM
Guncrank,

You are remembering correctly. If you are cutting a new chamber, those two are all you need. But if you are looking at a gun with some wear, the Field NO-GO is what you need to see if it's still in spec.


Mr. Guffey,

An excellent point about the low number failures. Hatcher's investigation dealt with a relatively small total number of failures; about 1 in 15,000. But there is no central record system for reporting subsequent failures to know what the number has come up to. A few collectors have succeeded in shattering some with a hammer. There's an example of your shock. But how many failed in actual use with normal ammunition at the pressure they were designed for originally? Nobody knows if it is significant or trivial.

It's one of those questions that, if a giant pile of money magically fell in my lap, I'd be tempted to investigate. The only method I can think of, since many of the old guns and past owners have gone, would be to buy up a large random sample and proof them all and to see if they all survived.

airdrop
February 21, 2011, 10:35 PM
same look for a shop that has old bolts to try. If you find a bolt that locks up tighter do a swap.