Didn't want to hijack Marks thread so I started a new one. SR4759 brought up a valid point that begs this question.

I wonder if there has ever been an accuracy analysis of any difference in accuracy of the M98 system when the barrel is torqued against the receiver face versus the inner collar?

Not that I know of. And given the flimsy nature of the military 98 receiver, I personally doubt whether you could detect any difference. Too many other variables. I would do a test but don't have time and it is too cold. Seating against the inner collar, which is and was, standard practice, theoretically should be more rigid, but as I said, you would be hard pressed to prove it. Maybe. I cut them so the inner collar is seated hard and the outside shoulder is touching.

My thoughts about it are like DPCD's.
The thumb cut and the receiver rails are the biggest detractors of rigidity for the 98 Mauser receiver. The receiver ring is relatively massive and short and will resist flexing much better than the open span of the loading and ejection port.
I think the difference is so minuscule as to be unimportant. Whenever accuracy is critical a much stiffer action should probably be considered.

I've read many times over the years that accuracy suffers when both the collar and the ring front are bearing on the barrel. Supposedly testing was done which showed that result.

Frankly, I have never believed that assertion for even a moment.

When I was young I was taught a bit of barreling/machining by one of the best Canadian gunsmiths I have ever known...Doug Paul of Edmonton, Alberta. Doug always fitted his barrels to about .001 "crush" at both points, so I started out doing the same.

Very quickly I began to doubt whether ANY crush was required at either point. It seemed to me that with a right hand twist barrel every shot would initially be exerting some tightening of the barrel in the action as the bullets "took" the twist of the rifling. The torque created is not strong, just enough to keep a good tight fit of the barrel to the receiver.

I have barreled Mausers with minimum contact at both points ever since and it has always provided very good accuracy for me.

I don't install left hand twist barrels in Mausers (or any other right-hand threaded action) because that same light torque can eventually loosen a left-hand twist barrel that is not crushed to the receiver by about .003". I saw one shooter lose the Alberta Provincial Championship in about 1978 because he had his "left hand Twist" barrel come loose on the last target of the four-day tournament and he ended up "saving" about 7 rounds on that target. Up 'til then he had about a 3 point lead in the overall aggregate, but losing 70 points on the last target put him into almost last place.

If there is a difference, its minimal and only applies to such as bench rest shooting...And the 98, the pre 64 mod. 70, the Enfield, and the Springfield and other clones are still the best of the "hunting rifles" and the bases for 99.9% of the quality custom rifles.

There is so much BS out there mostly started by experts who overthink a subject and decide it "must be so" and the masses follow suit because he said he said so it must be true..like sheep to slaughter.

The thumb slot in a Mauser is one such myth IMO I don't buy off on, and know of no study to prove it, too many Mausers shoot sub minute groups to let it concern me...I belive accuracy mostly has to do with the barrel,and inletting to lesser degree. I have not seen any difference in accuracy in comm. FNs without thumb slots and 98s with them, and would bet dollars to donuts with anyone to prove to me there is.

I don't believe there is any difference between a good double cut Mauser or a C ring action, they both work just fine.

I don't believe that one needs to tighten a barrel to the action as many do..actually you can tighten a barrel hand tight if your a strong little buckaroo and it will work just as well and just as long. On my switch barrel I give it a gentle tap with a lead hammer, that is and has been more than sufficient.

I don't believe that free floating is all mighty the last word in bedding, mostly its wonderful because all one needs is and axe to do it and its simple and indeed it works well with some guns, but not all, not by a long shot.

I don't believe there is any difference between one piece bases and two piece bases as to strength and accuracy, or the ability to load a bolt action rifle, as claimed by many, most of who have obviously not used both IMP.

I don't believe a bolt handle on a big bore has to come straight down because a mod. 70 swept back will hit your hand because of recoil..I do believe a straight down bolt handle is sho nuff purty on a big bore, so I use them

Cheek pieces and Ebon forends are cosmetic!! I believe that one.

I "think" I believe that a recoil pad gives a rifle a one inch run at your shoulder, and they are not necessary if you hold a rifle properly. Jack Belk told me that one!

And if you think its bad with Mausers you should hear the BS being spread about double rifles such as you can't shoot monolithics in them, you must pull the front trigger first as thats the way the were regulated, btws pulling the rear trigger first will stop thoes two barrels from going off together in most cases not to mention that POI does not change either way. Then the soothsayers banned the use of 4831 as it was causing blow ups, and IMR3031 created rings in the barrel...and a hundred othe myths..

I think, I will tie my horse to the rail in the alley to make a quick get away after the masses read this post!

What Ray said.

While building and playing with wildcats I would often only mount the barrel basically hand tight. Hand tight, crushed to the shoulder, enter ring or a little of each I never saw a difference that made me stop and think.

The 98 is a GREAT HUNTING action. I simply wouldn't use it as the basis or a BG rifle.

+10

Any quality turnbolt action will shoot MOA or better. Most of these "experts" have never shot a National Match 1903 Springfield or a well tuned Krag, SMLE, P14 or P17. All will shoot MOA or better groups and have stood the test of battle as well and the tiny number of shots in target shooting and hunting.

Nobody is using any of these actions to shoot tiny little holes off a benchrest so the "question" if of no interest. Any big game rifle that put 3 shots in 1.5" @100 yards, in the hands of an ethical hunter, will kill any big game animal that walks.

Heck, we have ARs today that shoot bugholes and you can screw in a Savage or Marlin barrel with no nut and it will shoot sub MOA groups.

I would not worry about the "masses" ...... most of them might fire 100 rounds per year and have no idea what the OP is even talking about.

My personal belief is that from a modern barrel fitting standpoint, the C-ring or diaphragm as some have called it, is a much overrated feature of a 98 Mauser. You can ignore it completely and barrel a 98 as you would any other bolt action, in effect, by truing the receiver ring face and torqueing the barrel against it leaving a gap between the barrel end and the C-ring and you would have a rifle that shouldn't behave any differently than any other bolt action rifle. The C-ring may add a little strength to the receiver, but that would be negated by the cut behind it for the locking lugs and the cuts for the barrel threads. I feel a most important feature of the C-ring is from a manufacturing and assembly standpoint. I realize that there would be more machining costs to the receiver associated with the C-ring, but because of the C-ring the 98 military barrel cheaper to manufacture and easier to install than other barrels of the day. Military barrels are generally machined without a shoulder thus they are designed to torque against the C-ring. The shoulder on the barrel is the same diameter as the major diameter of the barrel threads. The end of the barrel is machined flat to tighten against the C-ring. By machining the C-ring in the receiver the Mauser has the advantages of a cone breech, similar to a 1903 Springfield or a Winchester Model 70, without having to machine a shoulder, cone, an extractor cut or "timing" an extractor cut on the barrel. Barrels would have been made in much greater quantities than receivers. I'm not saying that I would change anything about the Mauser action, it is the best out there. I just feel that torqueing the barrel against C-ring was more important with the military barrels than it is to us today.
When fitting a barrel to a 98 receiver, I have always cut the thread length the same as or .001" longer than the depth from the receiver ring face to the C-ring. T was actually called a "Barrel Plumber" on another post on this forum for not fitting the barrel "properly", tight against the C-ring and leaving a small gap at the receiver face. With the measuring tools we have available I see no reason to leave a gap no matter how small.
These are just my opinions and you know what they say about opinions, they are like feet, everyone has a couple and they usually stink. I also have the same proof to back up what I've posted as about 99% of the rest of the stuff you will read on the internet .

I just cut both faces to hit at the same time and tap with a lead hammer.

Never had 1 come off yet.
I can't see why it would not work with a crush fit or a slight gap.

But what do i know.

Because it works either way. Hell, most receivers do not have an inside ring so what difference does it make, except easier fitting, as stated above.
I do like to put a few pounds of torque on barrels, maybe 30-50. Just a good pull on the handle. I don't want them to fall off.

I was taught at TSJC to measure the distance from the face of the reciever (and I cannot remember ever being told to turn this surface true) to the ring and then to turn the tenon on the barrel to this length and place a small relief at the juncture of the threads and barrel main body. Then thread and turn on the action and snug up - PERIOD. I have never fitted a barrel any other way. Usually they can be turned on and snugged up by hand and then it takes a wrench to unscrew. I had a little strap wrench I used to tighten them up with. I have absolutely no idea which surface they were actually fully bearing on and really don't believe it makes any difference.

At CST I think they taught us to snug the M98 to both rings or shoulders. At least that was how I did mine .Glass bed the receiver + 2" of barrel .Anyway it was at least MOA and got lots of deer !

One advantage that the C ring does do is allow the barrel to be turned to a smaller OD (about 1.125) ahead of the receiver ring. Allowing for a lighter barrel. The actions that must be torqued at the receiver face do not make this option possible.

quote:

At CST I think they taught us to snug the M98 to both rings or shoulders. At least that was how I did mine .Glass bed the receiver + 2" of barrel .Anyway it was at least MOA and got lots of deer !

What I was TAUGHT as well. I will admit to probably following it around 50% of the time. 2" glass on the barrel all the time.

quote:

Originally posted by D Humbarger:
Didn't want to hijack Marks thread so I started a new one. SR4759 brought up a valid point that begs this question.

I wonder if there has ever been an accuracy analysis of any difference in accuracy of the M98 system when the barrel is torqued against the receiver face versus the inner collar?

The barrel should only be torqued against the inner collar and should not touch the receiver face.

Guys, let's move along. There is no right or wrong answer, only opinions that are now lapsing into chest thumping.

Heresy but a well set up Savage bolt action will outshoot any Mauser ever made and cost 1/3rd as much. As long as the barrel does not fall out it really matters not what abuts what.

As I said, my gunsafe holds some expensive ARs (cheap compared to most Mauser customs) that will shoot smaller groups a lot faster and reload right now compared to any Mauser.

quote:

Originally posted by metalbeater:
Guys, let's move along. There is no right or wrong answer, only opinions that are now lapsing into chest thumping.

Heresy but a well set up Savage bolt action will outshoot any Mauser ever made and cost 1/3rd as much. As long as the barrel does not fall out it really matters not what abuts what.

As I said, my gunsafe holds some expensive ARs (cheap compared to most Mauser customs) that will shoot smaller groups a lot faster and reload right now compared to any Mauser.

Your post is completly irrelivant to this thread. Chest thumping about a Mauser is more relivant than you posting about Savages and AR's.

Here is something that I would like to interject into this discussion. I believe that there is a difference in accuracy between barrels that are NOT a 55 degree Whitworth threads and those that are. I have nothing scientific to back this up, just my prior experience. Has anyone else had this same experience???

I was taught that a Mauser barrel was to seat on the inner ring and just touch on the outer. I continue to practice this as well as to use the 55 degree Whitworth threads. I also do not believe in torquing the barrels on, a little bit of blue loctite can do wonders....

Never heard of a difference in five degrees of thread angle on accuracy or anything else. Any source, proof, docs?

As I stated I have nothing scientific, just my own experiences. Based on these I believe that it can contribute to accuracy issues. It may not be the main cause but it was not helping.
One thing to keep in mind is that not only is a Whitworth form 55 degrees but it has a .0115 radius at the crest and root. Because of this, the depth of the BSW 12 pitch thread is .0534 while the depth of the same pitch sharp V American Unified thread is .072. It is easy to thread a barrel so that the crest of the thread is contacting the radius at the root of the BSW thread while the flanks are not making contact.

Dirk,

Once the barrel is torqued against the c-ring or shoulder, or both, the flank is now in contact due to the force of the thread pulling up to the shoulder, c-ring, etc.

The determining factor now is how much torque. Lots of torque deforms the barrel thread and makes it conform to the action thread (assuming the action is made of harder steel). Low torque and it just kisses the thread flank. A crush fit as some call it doesn't deform the shoulder as much as it deforms the threads.

I believe that a little torque is needed to seat the threads and get good contact throughout. Otherwise, there could be some non-uniform elastic stretch occurring.

That said, of far more importance is the proper alignment of the bore, chamber, thread, action, and bolt face. Then the barrel will do the best that it can, but the bullet has to get a straight start.

In the case of a Mauser, and using my logic above, the barrel should torque against the part that is machined true to the bore. If that is the c-ring, use that if not use the ring face. Just my opinion.

Jeremy

quote:

Originally posted by farbedo:
Dirk,

Once the barrel is torqued against the c-ring or shoulder, or both, the flank is now in contact due to the force of the thread pulling up to the shoulder, c-ring, etc.

The determining factor now is how much torque. Lots of torque deforms the barrel thread and makes it conform to the action thread (assuming the action is made of harder steel). Low torque and it just kisses the thread flank. A crush fit as some call it doesn't deform the shoulder as much as it deforms the threads.

I believe that a little torque is needed to seat the threads and get good contact throughout. Otherwise, there could be some non-uniform elastic stretch occurring.

That said, of far more importance is the proper alignment of the bore, chamber, thread, action, and bolt face. Then the barrel will do the best that it can, but the bullet has to get a straight start.

In the case of a Mauser, and using my logic above, the barrel should torque against the part that is machined true to the bore. If that is the c-ring, use that if not use the ring face. Just my opinion.

Jeremy

A prooven way is Loctite on the thread and some medium hammer force against the recoil lug to torque the barrel.

Hmm. Found these in my Kennedy Chest. Wonder what the numbers mean.

Don't think I will be taking a hammer to this very nice 1909 Argentine action that was in the original cosmoline when I bought it way back in the 70's.



Or to either of these virgin Mark X actions that I also purchased many years ago:



Fine clasic actions do not deserve hammers.

We need a chest thumping graemlin.

quote:

Originally posted by WoodHunter:
Don't think I will be taking a hammer

Fine clasic actions do not deserve hammers.

Use a copper, brass or aluminium mandrel between the action and the hammer and nothing will be destroyed
It`s a prooven gunsmith routine.

Can those that replied that the barrel must be fitted tightly against the c-ring without touching or lightly touching the receiver face, please give us a reason for this.

quote:

Originally posted by Mark Poley:
Can those that replied that the barrel must be fitted tightly against the c-ring without touching or lightly touching the receiver face, please give us a reason for this.

The receiver face does not fit to the c-ring and then you get a tenseness.
0,004 free space (a sheet of paper) between receiver face and barrel is enough to prevent tenseness and when the gun is ready, this space is not visible.

When fitting a barrel to a 98 Mauser, I always measure from the face of the receiver to the c-ring in several places to make sure the receiver face and c-ring are parallel. On the rare occasion that I find they are not, I chuck a scrap piece of round stock in the lathe. I face and thread this as you would a barrel shank and snug the receiver up on this mandrel, then lightly face the receiver to clean up true. This only takes a few minutes and elimimates any stresses that would be caused from the receiver face and the c-ring not being parallel. You can make a permanent mandrel to use in a collet attachment on the lathe or a spin fixture on the grinder and not make a new one each time. I have a collet attachment for my lathe , but I can make up a new mandrel faster than I can remove the chuck and install the collet attachment.
When I machine the barrel shank, I turn the shank length the same as or at the most .001 longer than the depth of the receiver from the face to the c-ring. My barrel wrench has a 24" handle, so I tighten the barrel with moderate pressure on the handle. Probably guessing I would say somewhere around 80-100 ft. lbs.

I can't say I've ever done any real analysis but this is because I have never built a target rifle on a Mauser ate all. Buiolt a ton of sporting rifles, mind you.
I always fitted Mauser barrels by cutting the barrel tenon .001" to .002" short. In practice, when the barrel was tightened up, the shoulder compressed and the threads stretched until contact with the inner seat was made. This may be good practice or it may be poor but it is MINE!! My Mausers shoot real well. The barrel is set up damned tight (gunsmithing terminology).
I face the receiver by hand, with a file and stone( "oh, what a hack!", some of you are no doubt thinking) until the face is parallel with the inner seat as measured with a depth mike. Dy Kem on a test gauge confirms the fit.
It has been common practice over the years to simply cut the barrel threads at 60 degrees. While this can work out just fine, I prefer to cut 55 degree threads. If the threads are cut at 60 degrees, initial contact is at the root of the barrel thread and the top of the receiver thread. This means it is most likely to be the receiver thread which deforms and I don't really like that.
Now I have built some target rifles using Musgrave actions. The Musgrave is a Mauser-like action with an inner seat but most simply seat the barrel shoulder against the face since the extractor protrudes ahead of the inner seat and it is just easier to allow clearance on the extractor and ignore the seat. I always preferred to fit the barrels the same as I would a mauser and make an extractor cut in the breech. I think it is important to note that my rifles didn't shoot any better than those which were fitted against the receiver face only. Not good chest thunping, I know, but there it is.
I have also always fitted Barrels to MKV Weatherby's the same way and utilized their inner seat. The same when I fit barrels to Barnard actions (not necessary to pick up the file for these though!).
When I built my 788 Remington BR rifle back in the seventies, I deepened the distance to the inner step in the receiver (so I could counterbore the barrel breech) and fitted the barrel as on a Mauser; .002 compression on the face and solid contact on the inner step. I eschewed the recoil lug since it was a glue-in.
All military mauser are fitted against the inner seat and this was the original design intent. Kind of hard to argue with that. Regards, Bill.

quote:

Originally posted by Mark Poley:
On the rare occasion that I find they are not, I chuck a scrap piece of round stock in the lathe. I face and thread this as you would a barrel shank and snug the receiver up on this mandrel, then lightly face the receiver to clean up true.

I use the same technique - also for Remington 700 actions where its realy necessary to clean the front surface on the lathe.