I'm just starting another new project (280AI) and am getting to work on the barrel to action fit. A question I've got is, which is more important on a VZ24 mauser, full contact on the front of receiver ring to barrel shoulder or full contact on the barrel face to the C-ring? Would a combination of both be the best way to go? I had a gunsmith chamber a 300wsm on a different mauser and he turned the front of the receiver on a lathe to square it up before chambering, but doing that is assuming that the barrel shoulder is square. I guess my root question is; which one is better or doesn't it matter as long as both are close and one is in full contact? I already started on doing both using lapping compound and have rub marks on both areas, but I'd sure like to know if I'm just spinning my wheels. Any facts, suppositions, or wild-ass ideas would be appreciated and respected.

thanks
lwells

I wells,
You can put the action on a mandrell that has threads that fit into the action. the ends of the mandrel are set in the lathe on centers and then when you trim the face of the action it is square to the threads. You do not need to lap those surfaces. You are spinning your wheels. In the class I just took from Mark Statton, he said to have equal contact on the two surfaces.

Wally a short chambered barrel just means that the chamber has not been cut completely to full depth.

[ 08-12-2003, 06:17: Message edited by: Customstox ]

Hey Chic what gunsmithing school is it you have been going to? Isn't it in Colorado? I know that there is one in north california and I was told that there is one somewhere in Pennsylvania or something.

thanks

Red

CHic:
One problem with the mandrel you refer to is the receiver threads/bore/face may not be all in correct relation to one another. Only when you can determine that all of these surfaces are concentric and/or perpendicular to one common axis can you be sure they are correct. By simply turning the face of the receiver with this fixture, you do not know if the threads are concentric or square to the bolt axis. Granted, the mandrel you speak of is holding the rear of the receiver and the threads in alignment, but how about the bore axis? Only after trueing up a receiver correctly I set the barrel shoulder up to bottom on both the receiver face and the C-ring simultaneously.
Incidentally, the Mausers were set up to bottom on the C-ring; the barrel tenon was usually of too small a diameter to make any difference to a fit against the face. I normally turn the barrel tenon to a larger diameter. IMHO

Jim

I Wells, I seem to get the best accuracy by squaring the receiver face and the barrel shoulder. I then measure the distance from the inner receiver ring to the receiver face with a depth mic and add about .001"-.002" to the shank length. This makes it somewhat of a "crush fit" when you tighten the barrel using a barrel vise and action wrench. This makes the barrel fit solid against both surfaces. The inner rings are usually square. If you're lapping anything it should be the bolt lugs and receiver raceway. Be sure to do this prior to setting headspace. Also try truing the bolt face. Doing all this aids in keeping everything on the same axis. Good luck.

The school in NoCal is in Susanville. It's called Lassen College. That's the one I've been going to.

I beleieve Chic was at the Trinidad State Junior college, the gunsmithing program there is a legacy of P.O. Ackley. There is another good gunsmithing school in Colorado - the Colorado School of Trades in metro Denver.

Iwells,

One area you should pay particular attention to is the correct headspace setting for the Ackley Improved calibers. Do a search of this site for ALL the previous discussions regarding headspacing for these cartridges...

Good luck,

Malm

My system:
With a home made a mandrel that is tight with the bolt bore of the VZ24 receiver and has threads, the threads are not what locates the receiver, the bolt bore does.

The receiver then gets the receiver face trued to the bolt bore.

Then the inner stop ring [or "C" ring] is lapped with another home made fixture, that again has threads, but locates on the receiver face.

The inner stop ring and the receiver face are parallel and the distance between them is measured with a depth micrometer.



Then with the barrel in the lathe, I cut the shoulder so the distance to the barrel face was the same as the distance I measured in the receiver.

Then when I torque the barrel on, with grease on the faces and threads, I get both the shoulder and face to bear a heavy force and thus make the barrel to receiver interface stiffer and more accurate.

With this system, I have not trued anything to the threads or chased the threads, and yet I cut the 55 degree threads to just barely screw on, and have never had a problem with VZ24s or Turkish Mauser screwing in tight against the receiver face. I put grease on the threads, inner stop ring, and the receiver face. I use ~300 foot pounds of torque and I think any error in thread to bolt hole in the original Mauser receiver manufacture is compensated with thread crush.

Imagine how much straighter it would be if you torqued them to 400 ft/lbs.

They screw on straight finger tight.
The torque is so they stay put and for stiffness.

Let me introduce myself, I�ve been looking at this board for only a few days. Chic is a friend of mine as well as one of my students at Trinidad State College. My name is Mark Stratton and I teach �Basic Rifle Barreling� for the summer NRA sponsored Gunsmithing classes. I got a degree in Gunsmithing at Trinidad in 1971. I�ve been rebarreling rifles for over 30 years and what I�m going to say in the following text has come through rebarreling well over 100 rifles.

With a Mauser 98, there are some things you take for granted. One of those things are that the action was made to tolerance. Because of the .011 to .031 deep casehardening you can't go back and remachine locking lug surfaces like you would a remington 700. You can remachine the bolt face for squareness and lap the lugs, but major rework is out of the question. One other thing to remember, these actions can be a 100 years old. After a 100 years, any action made by anyone can be worn out. Treat every action as a single unit and just look at the manufacturer.

When rebarreling a rifle every element of the project needs to be on the centerline of the bore. The only solid point you have to start with is the threads in the receiver. By using a mandrel (that was machined between centers with good accurate threads) and facing the receiver, the receiver�s face is now perpendicular with the threads. The C-ring of the Mauser might not be perpendicular with the threads. After taking several readings with a depth micrometer, the receiver face and the C-ring might not be parallel. I cut the barrel�s shank the shortest dimension from face to the C-ring and use only enough torque to keep it from unscrewing. For the best accuracy don�t over torque the barrel. If you thread the barrel between centers and turn all of its surfaces between centers the boreline will be the centerline of both the barrel and action. That seems to give me the most accurate rifle. With a 7-� pound sporting rifle, I like to see a minute of angle at a 100 yards (1-inch group). If you would like to see some of my work, go to www.gunmaker.net.

Welcome Mark,

Actually, I was always under the impression that the point of reference for truing the receiver was the centerline or axis, of the bolt tunnel. It is from this point that everything revolves.

It isn't that uncommon for the receivers threads and bolt tunnel to be out of whack to some degree with one another. Using the bolt tunnel axis as the reference point, makes all other truing and squaring operations, logical.

Regards,

Malm

Hi Malm,

The reason the threads axis is the centerline is because that where the barrel and it's centerline interact with the receiver. It's the barrel's centerline that counts. You don't want the barreled pointed out in left field because it and the bolt tunnel are the same. There are other things that rely on an accurate centerline like scope bases. The boltface needs is perpendicular with the boreline. If you draw a straight line down the bore, in a perfect world, in would inter the bolt's firing pin whole, down the center of the firing pin. It's not easy adjusting the reciever threads, barrel threads, boreline and bolt face to the bolt tunnel. Where do you start? One more thing, a Mauser is not a brenchrest action. Because of the casehardening you can't make the same adjustments as a remington 700. Just a thought...

[ 08-13-2003, 09:58: Message edited by: Mark Stratton ]

Malm:

AMEN, that is the point I was trying to get across. The only thing on an action that cannot be changed is the bolt tunnel/axis, therefore all else must be trued in accordance with the bolt tunnel. This includes the face, the inner "C" ring, the threads and also the bolt face. All components must be square and true to one common axis, the bolt tunnel, AMEN. Incidentally, why is it necessary to thread the barrel between centers. It seems everyone here who knows anything at all knows the bore on a barrel is not straight. Mark said "in a perfect world", etc, "they would intersect at the firing pin hole" or something to that effect. What the hell has that got to do with it? Set up a Remington or WInchester bolt sometime and see how far off the firing pin hole is running out. I know guys who set up the bolt with the tailstock center in that hole and wonder why they get a shitty job when trueing up an action.

The guy that uses 300 foot pounds to torque the barrel on is, IMHO, a fool. All you accomplish here is to stretch the threads. If you have equal pressure on the front ring and the C-ring and they are parallel, you get zero stretch in the threads.

The bottom line is: THE ONLY THING THAT CANNOT BE CHANGED IS THE BOLT AXIS!

Jim,

Based on my own experience, the only time I find it necessary to thread between centers is when dealing with an object that won't fit through the headstock of the lathe, or, has a barrel tennon that isn't "chuck" friendly. This includes barrels with soldered front sights, barrel lugs etc., that won't clear the spindle.

My first choice is always the chuck. But if I need to, and I do on occasion, I have no problem using the tailstock and a steady rest.

Speaking of barrel straightness, If folks could section one of their favorite target barrels in say 8" pieces, and then "eyeball" how far out of center the bore actually is, they might better understand how their barrel, and thus their groups, tend to shift as things heat up.

Regards,

Malm

Actually, Jim and Malmborg, when dealing with the case hardened Mauser actions, I thing Mark has it right. Unless you want to recut the case hardened threads (I certainly don't) then using the threads is the way to go.

On all other actions, As you have said, start with the bolt bore, true the threads to it, cut the bolt lug bearing surfaces and receiver face etc, etc...

Scott

Scott,

That is exactly the point of my post. If a person is not going to go to the trouble of setting the receiver up to obtain beneficial results, then why waste time doing anything. As in the case of the Mauser in question, It is absolutely pointless to attempt to true the receiver face and "C" ring based on the receiver threads, IF, the receiver threads aren't true to the bolt tunnel. Doing so might make someone feel better for having made an attempt, but it will do absolutely nothing to correct any problem that is present.

Iwells,

I don't know what your expectations are regarding the potential accuracy of this rife, but unless you are willing to devote the time and money to insure that the action is true and square to start with, then spending time lapping the barrels bearing surfaces to the corresponding surfaces of the receiver is probably a waste of time.

If it were me and I wanted to use the VZ24 action to make this rifle, I would accept the fact that this action is probably not going to yield target accuracy, but I would fit a good quality barrel to it as is, and shoot it. I would then devote my time and energy to developing a good load to use in it, that would produce the tightest groups possible for what it this rifle is.

Now, as far as which point of the receiver to seat the barrel against, assuming you have sufficient barrel diameter to bear against the face of the receiver, I would do as others have mentioned here, and set up the barrel to contact both the receiver face and "C" ring evenly.

One last word of caution, DO NOT use excess force or torque, to close any gaps that may be present between the barrel and receiver surfaces. It is better to let a partial gap exist rather than force something out of shape.

Good luck,

Malm

Malmborg - It's not really a matter of not wanting to take the time to set up the receiver to cut the threads, it's a matter of is it in the best interest of safety to start cutting through so many of the case hardened portions of the receiver?

Perhaps I'm just being a nervous nelly here, and it's no issue at all.

Regards,
Scott

Malm,

The last time you stop by a Sunday afternoon brenchrest match, how many Mausers did you see on the firing line? A Mauser is a hunting rifle, not a tack driver. My rifles will shoot a minute of angle, for hunting what else do you need.

One more thing on bolt tunnels, the mandrel that you use on a receiver, uses the same diameter as a bolt. If the bolt tunnel and threads aren't in alignment the mandrel won't screw into the receiver. I've only run into one receiver in 30 years that the mandrel won't fit and it wasn't a military receiver,it was a new Parker-Hale. Mauser actions make great rifles and usually shoot very well but the metallurgy of the receiver has its limitations.

Mark,

The question wasn't how suitable the Mauser action is for benchrest shooting. The fellow making the original post asked specifically about the best way to fit the barrel to his receiver. He went on to say, QUOTE: "I already started on doing both using lapping compound and have rub marks on both areas, but I'd sure like to know if I'm just spinning my wheels."

A discussion ensued in which different methods and opinions were presented, and then you came on board and introduced yourself as a qualified educator, and made the following statement regarding Rifles. QUOTE:"When rebarreling a rifle every element of the project needs to be on the centerline of the bore." I was pretty well on board with you until you made the following statement, QUOTE: "The only solid point you have to start with is the threads in the receiver."

That statement just wasn't true, so I probed the subject a bit deeper. When pressed, you said, QUOTE: "The reason the threads axis is the centerline is because that where the barrel and it's centerline interact with the receiver. It's the barrel's centerline that counts. You don't want the barreled pointed out in left field because it and the bolt tunnel are the same." What does that mean?

Anyway to bring this discussion home, I don't want the folks who are following this thread, to think that gunsmiths rely on the axis of the receivers threads for their point of reference when in reality that is not the case. There is an absolute "starting point" and it isn't the receiver threads.

Personally I don't care one way or the other because I would never go to this trouble with a Mauser action unless it was specifically requested. Not that they aren't worthy of this attention, some are. And not because it can't be done, it can, and quite easily where set up and machining is concerned. But no discussion can be complete without presenting facts. This forum is in itself an educational forum. Sometimes we have to be responsible with what we post or risk having folks walk away scratching their heads.

Regards,

Malm

P.S. I don't use threaded mandrels for truing receivers. The mandrels I use fit only the bolt tunnel. This way I avoid false readings caused by out of whack threads.

[ 08-14-2003, 22:46: Message edited by: G.Malmborg ]

l wells,
To answer your question, "Which is more important, the receiver ring or the C ring?", the 91/30 Mosin Nagant design dropped the C ring feature early in WW2.

I believe both is better, but the receiver ring is more important.

I have rebarreled two VZ24s. The last one is in 257 Roberts Ackley Improved and I tried hard to true the action for accuracy. I had never got a one inch group before that rifle, and it shot a one inch group on the first group. It has averaged .8" for all 14 of the 5 shot groups at 100m. I had someone shoot it who is a better shot than me. He fired 5 shots and got a .55" group. He quit and said that the gun was better than him. Of all the things I did for that rifle, I don't know which made it so accurate. Chasing accuracy is following a myriad of rituals from the folklore because life is too short to run controlled experiments on all the variables.

Malm,

Hers's how you barrel a Mauser 98. Mount the receiver on a mandrel ( if you would like a drawing contact me. Face the receiver ring. Measure the distance from the faced receiver ring to the c-ring. Take the barrel blank and place between the manufactures centers and turn the cylinder section, the cylinder section is now concentric with the boreline. Layout the barrel(measure shank length, cylinder section lenght and barrel length). Trim the breech end to lenght and place in a lathe chuck, using the concentric surface to just machined. Face the end of the barrel and using a center drill replace the counterbore for the lathe centers. Place the barrel between centers and turn the outside contour. Now the outside of the barrel is concentric with the boreline. This is done so when the barrel heats up, the steel will expand uniformly. Next, turn the barrel shank and thread. The barrel is now concentric with the boreline, the shoulder of the barrel shank meets the receiver squarely. Before chambering lap the lugs to insure proper contact. You might want to remachine the locking lugs of the bolt and take a facing cut on the bolt face. DO NOT remachine the receiver locking surfaces because you might remove the casehardening, it could be as shallow as .011 of an inch. When you conplete these steps chamber.

I think I've said enough on the subject. For those who have following the thread and might be interested, my next 2-week seminar on Mauser Action will start on August 24, 2004 at Sir Sandford Fleming College in Peterborough, Ontario, Canada. I will be back at Trinidad State College next July. The classes will be "Basic Rifle Barreling" and a "Basic Rhino3d". Rhino3d is a computer CAD program software.

Mark,

Do you ever teach at Lassen?

zir,

I haven't taught at Lassen, however I've been there as a summer student. Anytime there's someone I respect teaching one of the NRA's summer seminars I try to attend. I like to check out other professionals methods of gunmaking. I've been there 3 times. The first was in 1990, Maurice Ottmar was doing a stockmaking class ( Maurice and I went through Trinidad almost together, I was one year ahead). The second was a metalsmithing class with Roger Green in 1993. Most likely the best seminar I've been to. The last time I went to Lassen was with Chic Worthing, the class was by Mark Silver in 1995. It was worth a weeks time to see what he was doing.

I drive through Susanville several times a year. I a member of the American Custom Gunmakers Guild and we have a yearly show in Reno.

Any of you folks that insist on machining through the case hardening of a mauser please staqmp that receiver prominently. Don't want it blowing up if it ever comes to me

It is not written in stone that the bolt raceway is THE reference. Unless one is prepared to sleeve the bolt to very close tolerances it can hardly be considered a refernece with all the slop.

Bullets never travel in the bolt raceway. Once the rifle is in battery the base of the case must be against a boltface 90 degrees to it. The cartridge must be in line with the bore - makes no difference if it is in line with the bolt race way.

Wally

Mark,

That's pretty close to how I would do a Mauser too.

Thanks,

Malm

Man, I go off to work for a couple of days and...geez.

Honestly, I really appreciate the help and advice. I'm glad it stayed amicable (LRS forums come to mind).

I guess I should've clarified a couple of things:
1. I don't have a lathe, that's most important.
2. This is my hobby, not my profession. If I build up one gun from scratch every other year, I think I'm doing just fine.
3. I just started doing these about 3 years ago, so I'm still learning (more on each rifle).

Anyways, I've now got full contact on the inner and outer receiver rings and full contact on both bolt lugs. Took a lot of time, a little lapping compound, and 2 tired forearms. But I am pleased with the results. Next is smoothing the bolt face. A friend of mine cut off an old military barrel and worked that into a fixture for lapping in the bolt face.

I'll make a post from time to time just to tell SOMEONE other than my wife how it's going.

BTW, this will be my fourth sporterizing of a mauser.

1. 243WIN; shoots 65grain V-max into 3/8" at 100yds. First rifle, minimal accurizing and reamed/headspaced by hand.

2. 2 300WSMs; these I was smart enough to send off to a gunsmith for reaming/headspacing/testfiring. Had a cold,prickly feeling about punching out a 308 barrel by hand. Mine will put 180partitions into 1" at 100yds, the other is my brother-in-law's christmas/birthday/hanukkah/MLK day present; didn't get real serious with the loading before I gave it to him.

Anyways, if anyone asks, and if I can figure out how to put pictures on here, I'll put some up.

Thanks again for all the tips and responses. It's real nice to listen to people have a discussion when they actually know what they're talking about.

P.S. Be ready for more questions. Like right now>

Clark, if you lightly oil the threads and then reef that barrel on that fully trued action by hand as hard as you can, how much more rotational distance does that 300lbs-ft of torque buy you? If those receivers are 12tpi, I'm guessing you would have to get a pretty fair amount of rotation to change the depth by very much. Also, how much can you count on the actual firing of the rifle to cinch up the barrel, assuming it hasn't seen loc-tite? I've heard it done both ways, and was just wondering if there was any clear advantage on either one.

thanks,
lwells

I wells, Jim Kobe, Malm, et interested all;
Through all of this discussion one thing stands out. (tugging at my long gray beard) I arrived at the conclusions so emphatically presented by Malm and seconded by Jim K. when the both of them were probably still playing with cap guns hoping to some day get a "real" gun. It would appear that Malm is president of "our" organization,Jim 1st V.Pres.. Earlier members of the organization included such notables as Vernor Gipson, J.R. Buhmiller and Monte Kennedy. I have left a great many names out and mention three only because I have their copies of "The Book". Jim Baiar and I needled a member of Rifle Magazine staff about republishing it. Ultimately Wolfe Publishing Co did so. Whereas it is only about how to make the entire U.S. Rifle Model 1903 (Springfield) to include the exact dimensions,cutter teeth, cutting angles and the like, gages, Bayonet ,Stock, processes used- as of 1916- So very much of this manufacturing methodology was exactly the same as that employed for other bolt actions that you can see how they did it and go from there. One thing becomes immediately clear and this is the relationship between registry points for the work piece. Radially this is inevitably from the bolt bore. Inasmuch as the bolt bore was reamed to a particular diameter a large collection of mandrels was needed and fixturing was done using a very simple method using the mandrels to locate.
Most of the mausers were made using similar procedures. Fixturing is damned near a lost art these days, but as a method for producing a complex part consistently and easily in large numbers and on specification it is everybit as good as and sometimes better than so called modern CNC methods. Controlling the centrality of and the horizontal alignment of the thread section with the bolt bore was not that difficult in a receiver. From what I've noticed on this forum there does not appear to be anyone who has ever read this book or has it in his posession. ( or they do have it and pile it and other books in a stack to stand on so that it is easier to snitch cookies out of the cookie jar so's not to make noise and get caught by the cook)

Manufacture of the Model 1903 Springfield Service Rifle. I S B N O- 935632 -20 -4.(reprint 1984)
Wolfe Publishing Co. Inc. P.O. Box 3030
Prescott AZ 86032

Grinding and turning mandrels. Mine are made from defunct 98 Mauser barrels. The front section which enters the "C" ring is tapered. It is located at about 2.5 " from the old thread end of the barrel and is about 1.5" long. The under the bridge section on the apparently most used arbor is to a diameter on this one .706". This end is relieved on 2 opposite sides to about .690" leaving 2 "lobes" of the .706 diameter which will clear the lug slots. The bridge section starts through the "C" ring and arbor stops when the taper diameter matches the "C" ring diameter. A light thump to seat the taper end followed by a 90 degree turn cams the under the bridge section. Since the first one I made in 1947 there have been replacemnets for wear and tear and some refinements. For the last 30 years I have actually refined the "product" to where the threads are removed- to just clean up and a flat cut accross that ends to make it easier to hold in my vise with the smooth jaws which makes twisting the 1/4 turn easier on the hands. (If a wrench is needed go to the next size smaller arbor). The rear end of the 12.5 " long arbor is turned to a collet size which proved to be handy. To determine if the threads are at an angle to the bolt bore it is a simple thing to use a piece of mauser barrel on which I have turned a straight section over the chamber. This end is the part you collet or chuck after threading into the receiver. These must come in sizes ,too for differences in thread pitch diameters. If in spinning one in the lathe you find the tang end wobbling around like a sick harlot in a hay rack you damned well know the threads are eccentric to the bolt bore, skewed on an angle to it ,or both. This is correctable but considering replacement cost, with the mass of Mausers out there it is usually not worth the effort. If it is a square bridge, or the one grandpa brought back from WW II, then it is going to need correcting and cutting through the ultra thin skin of carburized skin in the thread area ( well, generally, this is so) ammounts to nothing strength wise. It does mean that you don't fit a usually undersized pre threaded barrel. It is rare to find a Mauser with a thread eccentric to the bolt bore by more than .004 and these turned up more often in WW-I
Prussian arsenal receivers- like Erfurt and Spandau. It was a government job working there.
300 ft.pounds of sock it to 'em torquing in the barrel? I can see wanting to be sure that the special bayonet adapter mounted on the muzzle end when employed for that use by a troop who always twisted the bayonet anti- clockwise on the withdraw wouldn't somehow aid in the unscrewing of the barrel, but ,then it makes you wonder how the Ross barrels ever stayed in place with effectively only one full thread. And then there were the press fit( no threads) GEW/Kar 43's that were sent to the troops without the cross pin..
Buy and read the book!

[ 08-15-2003, 15:47: Message edited by: systeme98 ]

l wells,
10 ~15 degrees of rotation from finger tight to 300 foot pounds of torque.

No loc-tite for me. I make allot of mistakes, and want a reversible process. Moly grease, even the last time I torque the barrel.

One last post before we beat this to death. Mark, Apparently you place a lot of trust in the centers in barrel blanks. I used to do my barrels in a similar manner as you, in the steady, but I found the centers in these barrels were NOT, repeat, NOT concentric to the bore. I had always re-cut them after indicating the bore to within a tenth or two. There is a problem with tis also; with the barrel not always being straight, one has to wonder how much runout is there in the bore over the point the barrel is running in the steady? Also, do you turn the outside of every barrel you chamber? Your contention that "when the barrel heats up" is full of holes. That barre that is not straight does not have the same amount of material from opposing sides, so what does that do to your theory. I think you place too mch emphasis on a barrel being straight and concentric throughout its lenagth. Why no explain to the boys how you set up your chamber reamer to cut the chamber? This should really start a bit of fission.

Jim

Jim,

My Mauser rifles will shoot under a minute of angle. If you don't like my mothods use your own. In this world it what works best for you. As you might know, I mill most of my rifle barrels into octagons or half rounds, that most likely will drive you nuts. I do mill or turn every barrel. The contours the barrel companies supply really suck.

Hey Jim, if you want to talk about chambering lets start a new thread.

[ 08-15-2003, 20:58: Message edited by: Mark Stratton ]

Jim,

Before we switch to chambering, please explain how you approch barrel installation. You say the barrels aren't straight, bores aren't straight, the manufactures centers are wrong, the wall sections are't uniform and you thread in a chuck.
What is the KOBE method?

I am not trying to de-bunk your theories, everyone has their own. I respect the operation you do on the octagon and have had you do one for me. It turned out great! I have a disagreement with your theories not your results and I believe we can agree to disagree. 'nuff said.

Jim

Jim,

You must receive a Copy of the GUNMAKER. The reason I write for the GUNMAKER is to past along my theories, jigs fixtures and tools is because no one else was doing it. People were dying and taking what they learned in their lifetime to the grave. By writing about a topic, it opens it up for discussion. What you have learned through your experiances is important. You might have found the missing link. Sometimes when I'm teaching one of the students bring in a gem of an idea for doing an operation. I'm interested in your barreling system. How do you over come the problems you have brought up?

While pondering through this thread for a while I noticed a seamingly universal opinion of how the barrel should lash up to the receiver. That being, both the inner ring and face of the receiver would somehow make this miraculous bond at the same time. I find this interesting for the fact that when you have two surfaces residing in the same plane, if they are both touching, only one can be the primary locator. In fact, if they are both touching, then neither one of them is seating properly.

We've always set the barrels to bottom out squarely on the inner ring, while leaving no more than a .001" distance between the barrel shoulder and the face of the receiver. This way the barrel is making guaranteed square contact with the inner ring of the receiver, and not being misdirected by the face.

It is impossible to have the barrel making equal contact on two square shoulders in the same plane. It is either resting on the inner ring, and being misdirected by the face, or vise versa. This is just basic mechanics.

If you want the barrel to seat accurately, it should only make contact with one of the surfaces, not both. If it does, one is simply counteracting the other.

As bores, threads, and centerlines go, the threads are the last thing that I would use to determine the action's true position, because they are without a doubt the least accurate of all the features. The bore is where it begins and ends, but if there's one, there's a bucket full of ways to accomplish similiar results that yield accuracy of 1MOA. Personally, that's where my rifles should hope they never get to, because they may very well be traded off. It's certainly not the benchmark for hunting rifles or anything else, but unfortunately the gun crowd tends to be easily satisfied.

I feel that If I hear, well it's good enough for hunting, or, you don't need accuracy like that to hunt deer with, I'm gonna puke.
As gunbuilders we owe it to our customers to provide them with the best they can get from us. That means that we must put forth all the effort necessary to provide them with that product. This includes education, training, and equipment. IMO, if you don't have the desire to obtain the best results for your customer, then you have no business building rifles.
There are of course exceptions, but sending a bolt-action rifle out the door, that won't group consistently under an inch with just about any load you throw at it, is rediculous. That goes for larger calibers too. Frankly, I'm extremely dissapointed if I can't get a rifle to shoot less than .75" at 100. In fact, I had one that wouldn't and I rebarreled the damn thing. My chamber as it turns out, was a little eccentric. I blamed myself because I should have checked the reamer before using it. It ultimately was the culprit, and met it's demise in my dippy dumpster.

Systeme98 - don't assume. I've spent many an hour absorbing what I could from that book. I was a CNC programmer/machinist at the time, and was quite respectful of what the people in Springfield were doing at the turn of the century. Since the copy I read belonged to a friend, I have continued to try and find it used, without success.

That said, if you still want to re-machine the case hardened threads and lug bearing surfaces in a Model 98 or 1903, then so be it. I can certainly learn from my betters. But my gut feel is to use a different action should the threads be eccentric, and will use more modern actions for rifles destined to be tack drivers.

Regards,
Scott

[ 08-16-2003, 02:01: Message edited by: Scott Thornley ]