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Discussion Starter #1
A shooter was having trouble with scuffed cartridge cases in an FN Model 98 on another thread and got me to thinking about this because some military 98s were ill -fitted and need correction.

The long Mauser claw extractor is one of the most important of the Mauser patents. The US Government was sued by Mauser for infringment and Mauser won the suit. The extractor is an ingenious design with many nuances and features but it can be the source of inaccuracy and rough operation in any Mauser. Just because it's brand new does NOT mean it's right.

Start with the bolt out of the gun with the extractor aligned with the right locking lug just as it is when removed from the action. Holding the bolt upright with the bolt face up, slip a cartridge under the extractor. Just as the rim covers the firing pin hole there will be a 'detent' caused by a very slight lump on the extractor pinching the rim between the springy extractor and the left-hand locking lug. That detent should be only about .007 to .010 thousandths and take about a pound or slightly less of pressure to push the case passed it so the case is centered on the bolt face.

Here's the test-- I've done this one with a 250 grain 35 Whelen round.

Holding the bolt horizontally, the loaded cartridge should STAY on the bolt face in any orientation. Rotate it around and then tilt the bolt and cartridge down and up and all around. The loaded round will wobble but it should NOT fall.

With the bolt held vertically, see if the loaded cartridge sits down flush on the bolt face. Many times, as shown here with an old JP Sauer bolt, the angle of the extractor cut on the cartridge case touches the angle on the extractor so the case won't quite sit down flush. Can you very gently fit the angle on the extractor so in misses the case? Or is it better to try another brand of brass to see if there's one that fits better? Many times the latter choice is easier and is the source of one load being better than another or flyers in other wise good groups. A rifle with a slightly oversized chamber sometimes doesn't like a case being nudged to the side by the extractor and micro-fitting that one point repairs it.

Grinding and stoning extractors is best done with the extractor dis-mounted from the bolt. Taking them off is easy, getting them back on takes a special plier available from Brownell's or made from something else.

When opening bolt faces to magnum size, the left locking lug has to be hand fitted for the 'detent' and the extractor has to be re-ground to fit as above. It is rare to see one done right and rough feeding results. It really pays off to be careful and cautious and understand the physics going on during feeding and extraction to get the most from a Mauser.

By showing a loaded cartridge 'hanging' on the extractor in all orientations, you can see the precision needed to make it stick. The vertical picture shows a slight interference preventing the cartridge from sitting flush on the face.
 

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Discussion Starter #2 (Edited)
I'm adding to the post to explain further pictures, tips and hints. One of the very best ways to really learn a subject is to teach it to others. Sometimes the details are lost otherwise.

Here is a picture with rather crude annotations made to it to show the relationship of cartridge head to the extractor in the Model 98. There has never been a stronger system in any bolt action rifle. When you see a broken M98 extractor or rim pulled off a stuck case/cartridge, the only question is, 'how big a hammer did you use?'

I'm about to post another message with pictures of dismounting and remounting a M98 extractor. It was a point of pride in gunsmiths school to be able to do it without tools. :eek:

The "Feeding Detent" is located on the lower half of the locking lug as seen in the picture.

When the bolt is closed, that detent is just left of center at the top and there is nothing touching the case rim when the bolt is closed BUT the extractor. Remember S3 = Accuracy equals Straight, Solid and Square.

"Straight" has been violated if the extractor is pushing the case off-center. BUT, the clearance should be very small. Three thousandths or so.

SEE "FINE TUNING" below.
 

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Discussion Starter #3
Sometimes its necessary to dismount the M98 extractor. Headspacing cannot be accurate unless the bolt is bare in every gun where it's possible.

As in most military rifles, disassembly is done without tools any time possible. The Model 98 has a bare action and barrel and magazine box screwed and safety screwed together. That's a pretty good clue they didn't want Hans the Hammer mechanic messing with it. The bolt is a different story.
The extractor comes off without tools easily. The extractor is not as easy to reassemble.

To remove the extractor rotate it just past the solid lug and then press inward HARD on the long section of extractor.

Pressing in on the extractor pivots the front end of the extractor away from the bolt and out of the slot so it can be rotated on around until there is no slot for it and the extractor is tapped straight off the front of the bolt.

This shows the attaching method of squared dovetails.

The ring that the extractor attaches to can be removed by simply pulling it apart enough to slip it off the bolt.

(caution If you put the bolt back in the action with the ring still on it but the extractor gone, the ring will expand and will catch and hang up in the rear locking lug recess. Grab the 'ears' and squeeze them together with needlenosed pliers and with your third hand, pull the bolt back out. Don't do that again!)

To reassemble just reverse the process in the same 'blank place on the bolt head. You'll probably need a plier to hold the ring closed enough to get the extractor started. Once the extractor is resting on the 'blank place' with the extractor hook lined up with the groove around the bolt heard, rotate it around and re-seat it as shown.
 

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Discussion Starter #4
FINE TUNING M98 Extractor

Above is a quickly cobbled together short course. Here's some details.

First Picture--- Military original M98 extractor from 1911. Note the straight line of the active edge and then the radius at the top. That straight line means that P. Mauser wanted positive contact between the bottom of the extractor groove of the cartridge and the extractor. We don't for accuracy reasons. I'm convinced Mauser made them that way because it was too much trouble to fit them 'right' in the military guns. Commercial Mauser Sporting rifles have the barest hint of a radius so that the knife edge of the extractor does not touch the case when the case is fully on the bolt face.

Second picture----On the lower corner of the extractor is a bevel that's very hard to see or create without the extractor being off the gun. That tiny bevel allows the case to start it's trip up the bolt face at a slight angle. Without it, there is a 'hitch' in feeding.

Third picture--- A good bit of nuance can be seen here. The extractor 'lip' is behind the 'claw' and it is the lip that gives the M98 extractor it's strength. All four hundred pounds of force is applied to that lip when the bolt handle has to be hammered open.
Notice the slight dovetail angularity. The bolt face groove the lip rides in has a corresponding angle that makes the extractor tighten its hold on the cartridge case as pressure is applied to the rear. Notice the slight radius on the lip so that it will ride up out of the slot when lifted (as it's shown) and rotated on around onto the 'blank place' of the bolt.

Fourth picture is a repeat from above showing the pertinent parts and places. These become extremely important when 'opening up' for a belted mag or oversized case. A Mauser will eventually get a cartridge in the chamber if given enough energy greased with a cuss or two, but there's only one way to do it 'right' as the designer intended.

The extractor's actions depend on proper presentation of the cartridge from the magazine. The test known all over the world is ----Will it feed four empty cases in a hurry?

If it's right it will.
 

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I can disassemble without problem, but unless it's "well broken in" my arthritic fingers won't be able to pinch that extractor collar enough to get it started! All said though, it's one cool system!
 

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Mr. Belk
My rifle failed the empty case test. Sometimes the case hit inside of the chamber at an angle that wouldn't let it feed properly. Other times my bolt would push the cartridge forward but not engage the case in the claw, out comes the cleaning rod. And sometimes it just worked like it should. It seemed to feed the best when it was taking a case from the left side of the magazine.
What is the remedy? And will it feed all four cases properly if it is fixed?
Your input is greatly appreciated
Cory
 

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Discussion Starter #7
Cory-- Congratulations on trying it!!

Making a Mauser feed as it did as a service rifle is about 90% observations and 10% black magic. My process might be different than others but it works for me.

When a gun starts out right and ends up wrong, the first thing to check is what was changed. Your rifle has a new bolt in it but the location of the bolt hasn't changed a bit, so the focus switches to the stock.

The action and barrel and the magazine box are separate and depend on a good relationship between them. It's common when new stocks are made or fitted to fit the M98 magazine box too tight on the sides which bows the side walls inward. That crowds the 'down rounds' and affects how the top round behaves.
The M98 magazine box should NOT touch the action but for the 'ears' sticking up in the back. There should be a 1/32" gap between the bottom of the receiver and the top of the magazine box.

If the magazine box is not the problem, its time to make up a dozen feeding dummies and go to work slowly feeding, looking, feeling, and figuring. Once metal is removed, it's GONE. In Mausers, .005 of metal is sometimes too much.

The Mauser depends on more geometry than a hive of bees but most of it is visible. The cartridges stack in the magazine in a 45 degree zig zag. The shoulder of the case fits just behind a narrow place in the feed rail. (If a bowed-rail action, see below). That narrow place cams the shoulder area towards the center of the action, but the other cartridge or the shelf of the follower nudges the front of the case upwards as it moves forward. Since the case is tapered and the magazine is too, both those facts pushes the cartridge towards the center. As the fat part of the case is pushed upward by the narrowing feed rails at the same time the base of the case reaches the narrowed 'shoulder' spot, the case is forced further upward and the bottom of the chamber is the final 'cam' that brings it to alignment just as the bolt closes.

In some cartridges fit to M98s, the feed rails are shaped differently to accommodate their obesity or weirdness.

The extractor is only one link in a chain with about two dozen links that must be in alignment with the Solunar Tables to feed four cases in a hurry. I would spend time finding where every 'hitch' is located and what stops the smooth motion of the bolt as it feeds as a first step. Looking close at the marks left on feeding dummies also tell what's catching or stopping smooth motion. With eyes of an eagle and the finger tips of a safe cracker and a few basic tools any rifle can be made to feed better.....but MANY have had 'Their tails trimmed too close to the ears' and succumb to Bubba's 'Duh moment of shade tree gunsmithing', too!
 

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Above is a quickly cobbled together short course. Here's some details.

First Picture--- Military original M98 extractor from 1911. Note the straight line of the active edge and then the radius at the top. That straight line means that P. Mauser wanted positive contact between the bottom of the extractor groove of the cartridge and the extractor. We don't for accuracy reasons. I'm convinced Mauser made them that way because it was too much trouble to fit them 'right' in the military guns. Commercial Mauser Sporting rifles have the barest hint of a radius so that the knife edge of the extractor does not touch the case when the case is fully on the bolt face.

Second picture----On the lower corner of the extractor is a bevel that's very hard to see or create without the extractor being off the gun. That tiny bevel allows the case to start it's trip up the bolt face at a slight angle. Without it, there is a 'hitch' in feeding.

Third picture--- A good bit of nuance can be seen here. The extractor 'lip' is behind the 'claw' and it is the lip that gives the M98 extractor it's strength. All four hundred pounds of force is applied to that lip when the bolt handle has to be hammered open.
Notice the slight dovetail angularity. The bolt face groove the lip rides in has a corresponding angle that makes the extractor tighten its hold on the cartridge case as pressure is applied to the rear. Notice the slight radius on the lip so that it will ride up out of the slot when lifted (as it's shown) and rotated on around onto the 'blank place' of the bolt.

Fourth picture is a repeat from above showing the pertinent parts and places. These become extremely important when 'opening up' for a belted mag or oversized case. A Mauser will eventually get a cartridge in the chamber if given enough energy greased with a cuss or two, but there's only one way to do it 'right' as the designer intended.

The extractor's actions depend on proper presentation of the cartridge from the magazine. The test known all over the world is ----Will it feed four empty cases in a hurry?

If it's right it will.
H Jbelk, thanks for such a detailed explanation of the workings of the mauser bolt. My bolt also takes some force to close and open and like Jake i thought it was a tight chamber. Will try the feed 4 empty cases first and also try some other brands but 25-06 is not a common caliber where i am. Hornardy and federal were both tight to chamber and eject and neck sized reloads were the same no worse, all with similar skuff marks like Jakes. Will also try to hold a case with the bolt out as suggested and also try some cases by hand to if they do indeed fit the chamber. Should have thought of that myself really but one can tend to focus on what he thinks the problem is rather than really thinking.
Thanks Graeme.
 

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Hi again Jbelk. Looks like mine is the same or similar, a cartridge drops into the chamber no probs and so does a fired case , the last little bit with finger pressure. The cartridges are not riding up the bolt face even though with the bolt out it takes only finger pressure to slide a cartridge up and they stop there and dont fall out. I think the extractor is touching the case as the bolt slides in and the extractor is being pushed hard against the case as its closing making the bolt hard to close and open. Have to have a gun smith have a look if i can find one. Thanks for your post.
Cheers Graeme
 

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Discussion Starter #10 (Edited)
Graeme---I'm frustrated that I can't adequately explain what I'm feeling and seeing so you could solve your own problems, but feeding a CFR action is MUCH more complicated than what is imagined. The case being fed is being urged, nudged, cammed, and forced to move up and to right or left without bending the bullet, scuffing the case or stopping along the way.

Try one experiment just to see what you feel. Feed a case and pay particular attention to where you feel resistance just to set a base-line of what forces it's taking to mar the case. Now change just one thing. Put a dab of grease on the bolt face and smear some under the extractor claw. Put no grease anywhere else. Try the same feeding process you did before the lubrication.
IF that drastically improves the feeding and does away with the scuffing, you know it is the interaction between case head, bolt face and extractor claw that is causing the problem.
IF the lubrication of the bolt face didn't help much (it will always help some) it means the problem is the chamber mouth and needs gunsmith's attention.

Edit to add-- Be sure to clean grease from the chamber area and bolt face before firing. Keep grease behind the locking lugs, not ahead of them.
 

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Graeme---I'm frustrated that I can't adequately explain what I'm feeling and seeing so you could solve your own problems, but feeding a CFR action is MUCH more complicated than what is imagined. The case being fed is being urged, nudged, cammed, and forced to move up and to right or left without bending the bullet, scuffing the case or stopping along the way.

Try one experiment just to see what you feel. Feed a case and pay particular attention to where you feel resistance just to set a base-line of what forces it's taking to mar the case. Now change just one thing. Put a dab of grease on the bolt face and smear some under the extractor claw. Put no grease anywhere else. Try the same feeding process you did before the lubrication.
IF that drastically improves the feeding and does away with the scuffing, you know it is the interaction between case head, bolt face and extractor claw that is causing the problem.
IF the lubrication of the bolt face didn't help much (it will always help some) it means the problem is the chamber mouth and needs gunsmith's attention.

Edit to add-- Be sure to clean grease from the chamber area and bolt face before firing. Keep grease behind the locking lugs, not ahead of them.
Thanks again Jbelk, made up some dummie cases today using old primers and the cases cycle ok, cycled 4 rounds also put some lube on the bolt face as you suggested. Sat for a while just cycling cases in out to loosen things up a liitle. The chamber mouth is smooth, finger test not mine as mine would not reach, the chamber itself is not bad quite smooth as i would expect with only few minor scratches on shell cases. The case still does not line up in the center of the bolt face when being chambered, If i load one case and halfway to the chamber undo the mag ie let it down and push the case up the bolt face with my finger it ends up in the center. Your suggestion of putting grease on the bolt and extractor has helped a little i think and made ir easier to pin point the problem area. The problem area i think is after the bolt picks up the round about half way to the chamber, the round is still in the bottom half of the bolt when i think it should be central, the skuff marks come then, and as the round is pushed forward the angle, as the round goes into the chamber forces the end of the round square on the bolt. My guess at this stage is the extractor claw has to much metal at the back between itself and the bolt face. I must thank you again at this stage my experience is with shotguns, thousands of shots and rimfire. 22, the only centifire was a. 22 hornet in the early days and now i have also a.223 that with handloads shoots touching groups.
Cheers Graeme
 

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Rev.

I am new to this forum and realize that this is an old thread, but I did a dumb thing and need help. I was attempting to check the headspace on an old 1943 98k mauser. I took the extractor off and put it into the rifle. Naturally it hung up because of the expanding pin. I didn't know about that! What can I do now to get the bolt back out of the rifle? Or is it a lost cause? Thanks for any help you can give. My bad. Please help.
 

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Discussion Starter #13 (Edited)
You mean the extractor collar expanded and wont let the bolt out? Twist a piece of wire around the 'legs' and then line it up with the right lug race-way and it'll slip right out.
With long, thin needle-nosed pliers you can reach through the right lug race-way and grab the legs, too.

Welcome to the shooters forum. We talk a LOT about guns!! :)
 

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Very good info. I altered my magazine floor plate so I can close the bolt with the magazine empty and altered the extractor to single feed a cartridge in the chamber. This on my Swede.
I left the trigger alone, after the first stage is taken up it is about 2# for sear break. I also kept the cock on closing. I did change the safety for a scope and bent the bolt.
When I changed the barrel I set head space with masking tape, made my action wrench and barrel wrench by hand. Made the stock from a cherry tree that fell in my woods. My second checkering job. Gun is amazing and .410 shells on the 100 yard rail are easy.
 

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You have not lived until you make a Mauser stock from a plank cut with a chainsaw.
Even worse is when a guy brings an 03-A3 with a $300 piece of wood and wants a stock with checkering. It was not inletted at all.
Jbelk must understand and has felt the fear to make the first cut. Most times it sits for a time before committing but when you begin, never quit.
Mr. Belk, I know you have felt it but you are a smith. Thank you.
 

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Mr. Belk,

Fantastic information! I am modifying an Interarms Mark X bolt face. This is just what I needed. Better than any published material I have found Thank You!

Scott
 

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Jbelk, thank you for your excellent write up and explanation. It was very helpful in setting up my CZ 550 in 458 win mag. I am struggling to find info on a problem that I am having with this action, the feed from the left rail can be made to overshoot the right chamber edge and jam in the right lug raceway ie the round goes past the chamber. There doesn’t seem to be any control over the cartridge that can bring it back to centre and chamber correctly if it has been shaken or bumped too far right. If the rifle is held straight up it feeds flawlessly. On my brothers 416 rigby, a gunsmith set it up to allow the round to slide up under the extractor 5 mm/ 1/4 inch before the chamber. Is this correct and do you have any pointers for me to straighten/ control the round into the chamber without overshooting.
 

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Discussion Starter #18
Nhoro-- I've seen this and cogitating now on how best to answer it with pictures. Give me an hour or two and I'll try to tackle your problem. I had a .458 Lott just last year with the same 'kink' in it and it was going to do battle with the buffalos!!
 
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