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CRF and the "snap over" problem
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one of us
posted
RAB in another thread remarked, that CZ�s extractor needs to be reworked, to snap over a cartridge rim of a round already ( by mistake or accident ) in the chamber. So as to correctly push feed in an emergency.

I own a Win 70 CRF, which I had already tested earlier. I don�t want to strain the extractor, but for me this is a necessary test to fully trust the gun. Worked like a charm.

As I read that remark from RAB / Dagga - ? I was 5 min later in my gun room, CZ and empty case in 9.3x62 in hand. Now, Doc was right, of course: the extractor did not snap over the rim!!! But the bolt closed!!!

I do not understand what happened. The bolt was closed, but on opening no case came out!

When tried with bolt removed from gun, case pressed straight agains the extractor, it would snap over the ring!

Did I change the case in pushing it in too far? Is there not enough room in the front ring to allow sideway movement of the extractor? I have to check, if I bent the extractor, but it afterwards fed ( CRF ) a dummy without problems, and extracted it also.

Any suggestions? What do I have to change? I want that feature, either if somebody ( who I might lend the gun ) just drops a round in the chamber, or, if I in an emergency to get an additional shot quick, I just drop in a shell myself.

thanks in advance Hermann

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Posts: 828 | Location: Europe | Registered: 13 June 2001Reply With Quote
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aHunter,
I have tried this with the unmodified CZ extractor in a 416 Rigby and 378 Weatherby.
It chewed up the brass pretty bad but did snap over with a lot of force, and did extract and eject.

Though the 9.3X62 has a pretty adequate shoulder (17*30'/0.0305" per side), you may be swaging the brass on up the throat, allowing you to close the bolt with some extra force required, especially if the brass is new and soft or well annealed, or there is slop in the chamber or action.
My guess.

The bigger 416 Rigby with a better shoulder (44* 53'/ 0.048" per side) or the belted 378 are not going to budge. They just get their rims chewed up.

A gunsmith can bevel the extractor to snap over the rim. I would have him check the headspace and locking lugs, and the lug recesses too. I doubt you have bent the extractor. Anyone good with Mausers should be able to handle the CZ 550, in my humble opinion.


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RAB

 
Posts: 28032 | Location: KY | Registered: 09 December 2001Reply With Quote
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It is a quite simple job with a small stone and a dremel or similar grinder. The concern and caution of forcing the rim w/o the bevel is you risk breaking the extractor, certainly something one doesn't want to do.

If you were able to chamber w/o the extractory clipping over the case, you either have a headspace problem, or set the shoulder back on that round.

 
Posts: 7213 | Location: Alaska | Registered: 27 February 2001Reply With Quote
<Cobalt>
posted
I chambered an empty case in my Brno 602 .460WM and it extracted just fine. Repeated the test multiple times with the same result. The extractor snaps over the rim and the case ejects perfectly. Cobalt
 
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Cobalt,
Someone has hit a lick or two with a stone or dremmel on your extractor to make it work. Obviously a smith has worked it over as BRNO ZKK 602's did not come from the factory as 460 Weatherby. Good choice for a proper 460 WBY.

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RAB

 
Posts: 28032 | Location: KY | Registered: 09 December 2001Reply With Quote
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Picture of ForrestB
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I always heard the cure was opening the extractor slot in the front ring to allow the extractor to slip over a chambered round. Obviously this is more work than trimming the extractor bevel, but it sure seems like a better idea.
 
Posts: 5052 | Location: Muletown | Registered: 07 September 2001Reply With Quote
<Cobalt>
posted
Ron,
I had the .460 built about 12 or 13 years ago. I found a .375 Brno for real cheap and bought it just for the action. The smith that built the rifle did not do many DGR's so I wonder if he would have known to modify the extractor. Perhaps it was done before I bought it as a .375 as I never shot it prior to rebarreling. Cobalt
 
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aHunter's post points out a very disturbing aspect of the use of CRF actions for dangerous game (or any other type game) rifles. Many of them, most especially those built from surplus Mausers, will NOT accept a cartridge fed directly into the chamber without first running it through the magazine. The consequences of this are obvious. If you have a CRF action, be certain how it chambers individually fed rounds before taking it afield.
 
Posts: 13239 | Location: Henly, TX, USA | Registered: 04 April 2001Reply With Quote
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Modifying the Mauser to close over the rim of the case will drastically weaken the extractor and is a poor alteration on any Dangerous Game rifle....

It is just as quick to push the round down into the magazine and close the bolt..keep that powerfull extractor that came on the battle rifle, its there for a purpose and that is to extract an overload with dependability....

I used to use this modification until I had an incident..I replaced all my extractors and learned again the genious of Paul Mauser.

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Ray Atkinson

ray@atkinsonhunting.com
atkinsonhunting.com

 
Posts: 41926 | Location: Twin Falls, Idaho | Registered: 04 June 2000Reply With Quote
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This is exactly why I use a M700. Never I repeat never have I had any feeding issues with my M700s. The mauser extractor is nothing short of an accident waiting to happen to you in my opinion.

I mean what good is a strong extractor if you jam the rifle up while feeding the round into the chamber. That is why I say a M700 is a far superior choice for a dangerous game rifle. I guess it just takes the traditionalists a long time to realize that they have been wrong all this time.

Kent

 
Posts: 116 | Location: Cleves, IA | Registered: 14 July 2003Reply With Quote
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I've stepped into this mess before so ain't taking sides.

But please remember that the original Mauser magazine follower prevented the bolt from closing unless it was pushed down. I.e., you could not just drop a round in the chamber and jam it with an extractor that would not snap over. The round HAD to be fed from the magazine else the bolt wouldn't close.

I guess one could be a complete dunderhead and drop a round in the chamber and then manually depress the magazine follower to trty to close the bolt, but in that instance the buffalo/elephant/grizzly would be doing the human gene pool a great favor with the inevitable results.

 
Posts: 1027 | Registered: 24 November 2000Reply With Quote
<leo>
posted
Well, I would think that in the heat of battle it would be good to be able to push feed a cartridge just in case. We had an old J.C. Higgins(Sears) FN mauser that would lock down on a push fed cartridge with "some effort" and no damage to case rim. Ray in Alaska in another thread posted that his older model 77 that was push feed was converted to true control feed and that it will snap over a chambered cartridge easily. As for the statement that push feed is the best DGR action, I think very nearly every PH will disagree with that. All I have to do is push the case rim down in the feed rails(bullet angled up) and the extractor claw will ride over it nicely.
 
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HO HO HO!

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So many bovids! So little time and money!
RAB

 
Posts: 28032 | Location: KY | Registered: 09 December 2001Reply With Quote
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You are correct about the CRF bolt in my Ruger Rifle. If I want to push-feed a round into the chamber, the claw will slip over the case's rim when the round is in the chamber. This happens as soon as I move the bolt down. The front edge of the claw is beveled the same way bolts of BSA rifles are. These rifles, like mine, are designed to feed the chamber both ways.

The Ruger semi-CRF bolt only push-feeds, but it also allows the claw to slip over the case's rim once it is in the chamber. My rifle has these two bolts, but I only use the CRF one.

The fact is that I don't see any reason why I should have to push-feed a round into the chamber in an emergency, so I let the rifle do its work as a CRF one. Also, I can slip a round (angled) under the bolt pretty fast, and be assured it won't fall on the ground. This is what I do when I want an extra round in the chamber.

If I am hunting in bear country and a bear charges from within a few feet, I doubt I would be able to fire more than one time. If I am lucky enough to fire one time, I still have three rounds in the magazine. I just can't figure the idea of having to push-feed another round in case of an emergency.

[This message has been edited by Ray, Alaska (edited 12-15-2001).]

 
Posts: 2448 | Location: Alaska | Registered: 25 May 2002Reply With Quote
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I mailed with a Mr Frenzl at CZ, and he states their actions shall snap over the round just tossed in the chamber.

Also after I read from some Norwegian, who reminded me how to load one round "up". I just had forgotten it: So I put one round in the chamber and pushed in on the extractor from the side: voil�, the rim snapped over the ( live ) round. Yea, I know, did point the gun in a safe direction.

Next try: Norma and PMP live ammo worked. I will have the front of the extractor slightly polished, but no real metal removed. Now I know, if the mag floor drops, or I need another kind of bullet above a full mag, or I just get excited as hell, the action will feed and digest it, period!

I still wonder, if that empty case that the extractor did not snap over now has excessive headspace. It looked so exactly like the others I lost it between them ...

Moral of the story: ask, ask and ask. And CZ knew what I was talking about and anwsered very quick.

Good shooting to all Hermann

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Posts: 828 | Location: Europe | Registered: 13 June 2001Reply With Quote
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Picture of Robgunbuilder
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Ray has it correct as usual. The Mauser extract was not designed to snap over a rim and while you can get it to do so it will be weakened and may fail just when you need it most. I agree that the reason this often fails is because the bolt may be in actuality moving the case shoulder foreward or that the bevel on the extractor is not angled correctly to slip over and behind the rim. I suspect in some cases that the extractor may be opening on the rim and cocking such that it won't close over the rim. In any event I don't like this procedure or trust it. Use the Mauser the way it was designed and keep enough ammo in your mag for serious buisness.
As for the Rem 700. That extractor is a total piece of crap and should NEVER be used on a DGR. I have seen them fail to extract and even break. Just try and get a mag case out of one if the belt has expanded over .002 inches. I know what I'm talking about as this happened to me with a hot loaded .375 Ultramag that went overpressure in a 90 degree heatwave. Oh! Mr. NYATI please don't stomp me till I clear this thing with my cleaning rod! I have since modified all my Rem 700's (other than varmint guns for a Sako extractor as a result.
 
Posts: 6314 | Location: Las Vegas,NV | Registered: 10 January 2001Reply With Quote
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Kent,
the most breakable extractor in the modern world is the Rem 700 and 721, 722, you talk about crap thats it, constantly being replaced, apparantly you don't know crap from Shinolaf or a 700 extractor which is a tiny little piece of breakable steel, the Mauser is the worlds strongest extractor, always has been, followed by the M-70 (same)...

Leo,
why and how would one push feed a battle rifle, they are loaded with a 5 round feeder clip in the original battle rifle. the other side of that argument is its faster to pop the round down in the magazine as you have to close the bolt anyway, try it and you will see what I mean....

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Ray Atkinson

ray@atkinsonhunting.com
atkinsonhunting.com

 
Posts: 41926 | Location: Twin Falls, Idaho | Registered: 04 June 2000Reply With Quote
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quote:
Originally posted by ForrestB:
I always heard the cure was opening the extractor slot in the front ring to allow the extractor to slip over a chambered round. Obviously this is more work than trimming the extractor bevel, but it sure seems like a better idea.

This may be true as I have a M98K that was rechambered to 8mm-06 A.I. by Harry McGowen, and it will "push-feed" and extract just fine. I have replaced the extractor on this bolt with a surplus unit from Numrich without any modification, and it also functions in "push-feed" mode. There is nothing unusual apparent when the round is chambered thus, no load snapping noise or (appreciable) resistance. Case rims do not appear any different to the naked eye after being push-feed.

Can anyone confirm that this modification (extractor slot)will allow this?

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Life is more exitin' when yer stickin' suppositories inta a wildcats behind!

 
Posts: 2440 | Location: Northern New York, WAY NORTH | Registered: 04 March 2001Reply With Quote
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I'm not going to jump into the argument, just note an observation. I saw a cutaway view of the Mauser bolt/extractor system. The bolt has a groove cut just behind the face of the bolt, and the extractor has a "key" that fits in this groove. On my Rugers and M70, this is a "square" groove. On Mausers, the leading edge of the groove is at an angle (like a "dovetail" - narrower at the outside), such that pulling the bolt rearward pulls the exractor into the bolt body. The harder you pull, the harder the extractor is pulled into the bolt. If you were to modify the extractor for "push-feed", I would think that you would have to nullify this beneficial feature.

Bill

 
Posts: 1169 | Location: USA | Registered: 23 January 2002Reply With Quote
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I read this thread rather quickly so I may have missed something but the original point was about the CZ, not the Mauser. Yeah, I know they're damned similar...

My unmodified Enfields won't push feed but can be "snapped" over a round in the chamber. I'm assuming that a bevel could allow them to be push feed at the expense of strength.

It's been verified by others in other threads that the Mauser will do this without modification. It does require use of two hands to press the middle of the extracter but it can be done. Again, they can be push fed with modification at the expense of strength.

My question is whether or not the CZ can be made ready to fire on a chambered round by pressing the extractor. I'm assuming that it could go through the same modifications to be made push feed. I think the answer is somewhere in what Robgunbuilder said about moving the shoulder etc. causing the problem that started this discussion.

I agree with the "old f*rts" (no offense to you wise old fellows, I'm not yet 40 by the way) that one shouldn't mess with modifying that extractor. And another vote for the 700/721/722 extractor being a POS!! You shoot those high pressure loads and sooner or later that hole is going to open up and that sucker's going to come shooting out and if Murphy has anything to say about it it will be at a very bad time...stick to targets and non-DG.

Reed

 
Posts: 649 | Location: Iowa | Registered: 29 August 2001Reply With Quote
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It requires very little 'grinding ' to a mauser extractor to allow it to slip over a round in the chamber.I would advise that every mauser should be so modified if it won't already do so. At least twice I have had people's days ruined by accidently trying to close the bolt on a round in the chamber.More extractors are ruined by trying to close the bolt with one in the chamber than by 'grinding' a beveled edge. I have seen the bolt beaten open with a 2x4 on a mauser and the extractor did not fail. The idiot (me) mistook 4198 powder for 4895. It was not good.Mark
 
Posts: 109 | Location: Sask.Ca | Registered: 27 February 2001Reply With Quote
<Fat Bastard>
posted
Could somebody (sorry, "some buddy") clear up a couple of things for me? Just want to get some of the details straight so I know exactly what goes on.

1. If the Mauser-style extractor is to "snap over" the rim, doesn't it have to bend or move outward a little bit? Does that mean a rifle designed to "snap over" will have a clearance cut (or at least some room) in the forward ring to allow it (just as the Rem700 has a little space under its extractor to allow it to move)?

2. Does that mean a rifle that isn't designed to "snap over" doesn't have this clearance cut?

3. Does that mean that modifying a rifle so that it does "snap over" requires both bevelling the front of the extractor and making some kind of clearance?

4. Is an extractor not designed to "snap over" able to move outward at all? Bill M's post indicates the answer is NO (BTW, I never knew that about the Mauser - PPM thought of everything, it seems).

5. If you try to force a "snap over" on a rifle not designed for it, isn't the case being forced into the chamber by the front face of the extractor, rather than by the bolt face? Will that bend the extractor toward the bolt face so that eventually, the rim may not fit under it at all?

Edit: naturally, I'll be looking at my new LH M70 more closely tonight.

[This message has been edited by Fat Bastard (edited 02-26-2002).]

 
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Okay, I did a little experiment. I inserted an empty case into the chamber of the 8mm-06 A.I. and closed the bolt on it. I did here a slight "click" and slight resistance as the extractor closed over the rim. I opened the bolt and extracted the case. Absolutly no marks visible to the naked eye.

I then removed the scope and the bolt and inserted the bolt from another M98K 8X57 Mauser (unmodified in any sense) After I cycled the bolt to insure it would close properly, I inserted an empty case and closed the bolt. There was some resistance (more than with the proper bolt) and a somewhat louder "snap" as the bolt cammed closed. Upon extraction (it did indeed extract) visual inspection showed a visible nick in the rear surface of the case head, but no visible damage to the "rim".

Closer inspection of the bolts with the extractors side by side revealed that the 8mm-06 A.I. extractor was beveled slightly more than the 8X57 extractor. I must have performed this when I installed the extractor and forgotten that I had done so

I do not see where this modification would lead to extractor breakage as I would assume that any breakage would occur @ the inside root of the 90* corner where stress would be the greatest. This area is unmodified, and if anything, the slightly greater bevel on the face of the extractor would actually prevent breakage by allowing the extractor to ride over the rim.

I think that this would indeed be a wise modification to a DGR as it might "save ones bacon" if the error of inserting the round into the chamber (either intentionally or by a slip of the thumb) happened @ the worst possible time. The modified extractor is not beveled to a "point" and I seriously doubt that a brass case rim (soft) could break the heat treated extractor.

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Life is more exitin' when yer stickin' suppositories inta a wildcats behind!

[This message has been edited by wildcat junkie (edited 02-26-2002).]

 
Posts: 2440 | Location: Northern New York, WAY NORTH | Registered: 04 March 2001Reply With Quote
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quote:
Originally posted by wildcat junkie:
I do not see where this modification would lead to extractor breakage as I would assume that any breakage would occur @ the inside root of the 90* corner where stress would be the greatest. This area is unmodified, and if anything, the slightly greater bevel on the face of the extractor would actually prevent breakage by allowing the extractor to ride over the rim.

I think that this would indeed be a wise modification to a DGR as it might "save ones bacon" if the error of inserting the round into the chamber (either intentionally or by a slip of the thumb) happened @ the worst possible time. The modified extractor is not beveled to a "point" and I seriously doubt that a brass case rim (soft) could break the heat treated extractor.
[/B]


EXACTLY!!

 
Posts: 2356 | Location: KENAI, ALASKA | Registered: 10 November 2001Reply With Quote
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I think the snap over is a safety feature, as well as preventing breakage. I don�t understand the talk about military Mauser�s:

as we all know, recruits will do things no hunter would ever think of. So for safety�s sake Mauser will have built in that snap over capability. The empty mag problem was adressed by the back of the follower being square. Do an angle there and the bolt will close on an empty chamber. Perhaps a DGR should have the follower exchanged for one with a square back, so you never may close on an empty chamber in a Buff encounter? If the rifles "bomb bay doors" open from recoil, the follower is out of the way, and you may single feed.

I also don�t understand why the snap over capability will weaken the extractor: its just polished up front, there is hardly metal removed, and the back side is not changed: neither angle nor roughness.

So I think EVERY CRF should enable snap over.

Anybody any ideas about my empty case? Excessive headspace or not? Shall I repeat the test? And then discard good, usable x62 cases :-(( ?

Good shooting! Hermann

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Posts: 828 | Location: Europe | Registered: 13 June 2001Reply With Quote
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quote:
Originally posted by aHunter:

Anybody any ideas about my empty case? Excessive headspace or not? Shall I repeat the test? And then discard good, usable x62 cases :-(( ?

Good shooting! Hermann


aHunter: If you go back and study the results of my experiment, you will notice two things.

1: The extractor of the 8mm-06 A.I. bolt was beveled slightly more than the issue 8X57 bolt extractor. It was also polished. However, as I stated, it was not beveled to a "point" but had perhaps 1/2 the thickness @ the edge compared to the issue extractor, hence almost twice the bevel.

2: The issue 8X57 extractor offered more resistance than the modified extractor, and did mar the softer brass case head rear surface before (reluctantly) snapping over the rim. This would indicate that considerable laterel force (thrust)was applied to the case head before the unmodified extractor was FORCED over the rim by camming action.

Bear in mind that these cases were fire-formed to the rifles chamber and only partialy full length resized. I set my sizing die so that it is perhaps .015" or so from the shoulder when the press is @ full stroke. This method results in virtually zero headspace! This is with a case that has a 40* shoulder.

If your 9.3X62 cases are full length resized, or worse yet, unfired, and the extractor is in the same state as my 8X57 unmodified (issue) extractor, I could see where enough force could be exerted on the case to deform it.

Rest assured that I will not subject the unmodified 8X57 extractor to this type of ABUSE again! Before that weapon is put into use,(it was just given to me by my brother)I will bevel and polish the forward surface of the extractor! I would suggest you do the same. (I used a Dremel Tool with a Drum sander, followed by a polishing bit, it works "slikeransnotonadoorknob") After doing that, try a fresh case, preferably one that has been fired in the rifle.

I am assuming that some force was neccessary to close the bolt? (when you closed it on a chambered case) If not, I would have the headspace checked.

BTW: The 8X57 mauser my brother gave me has all matching #s, the bore is near perfect and it has been polished and blued. The exterior is spotless, and the bore appears to be likewise. I plan to get a set of dies and chronograph some "adult" 8X57 loads with IMR 4064 and Nosler 180gr Ballistic tips. I expect to get about 2800fps out of it. Then it is going to made into an 8X68S maybe? The goal is 3000fps with a 200gr Nosler Partition. 4000ft#s of muzzle energy.(from the 8X68S) Can you say SLEDGEHAMMER?

Anybody (BUDDY) have a good set of 8X57 Dies for sale @ a good price? (cheap)

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Life is more exitin' when yer stickin' suppositories inta a wildcats behind!

[This message has been edited by wildcat junkie (edited 02-26-2002).]

[This message has been edited by wildcat junkie (edited 02-26-2002).]

 
Posts: 2440 | Location: Northern New York, WAY NORTH | Registered: 04 March 2001Reply With Quote
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I feel like I should add a little to my previous post about the "angled" groove. I think that I saw the sketch in American Rifleman magazine a couple months ago, but have been unsuccessful finding a similar sketch on the internet. The groove is properly called the extractor guide groove, and the purpose is to keep the extractor from sliding forward/backward during operation.

The front of the groove is tapered towards the rear, and the front of the guide on the extractor is machined at a similar angle. I didn't think that the "inside" of the guide on the extractor (fat part) would come straight out of the "top" of the groove ("skinny" part), BUT I COULD BE WRONG. If the groove is cut wide enought, the extractor guide may be able to come away from the bolt far enough for the extractor to snap over a rim, so this may not be an issue.

The way that I recall the sketch, I did not think that the guide had clearance to come straight out of the groove. This would necessitate a wider (or square) groove on some portion of the bolt to allow the extractor/guide to be installed/removed from the bolt/groove.

I did think that this was an excellent design - the harder you pull on the bolt, harder the extractor holds against the rim.

I do not have any "true" Mauser bolt actions, so maybe "some buddy" who has one can finish the puzzle for me?

Thanks, Bill

 
Posts: 1169 | Location: USA | Registered: 23 January 2002Reply With Quote
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I put an empty case into the chamber of my Husqvarna FN Commmercial mauser and it did snap over, although I think it takes MUCH longer to do so then to simply place one down the mag..


The military mausers were made so they would not close without a round in the magazine. This was so that in the heat of battle a soldier could shoot away until when he cycled the bolt on an emtpy mag and it wouldnt close, obviously means its time to reload... Just makes it so they wouldnt have to keep track of how many rds they have fired.

If there is any doubt about the mag dropping rds out the bottom you should either get that fixed before you go hunting or if you are out hunting a peice of tape works well...

 
Posts: 935 | Location: USA | Registered: 03 June 2001Reply With Quote
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Wildcatjunkie, I used a _fired_ case from just that rifle. Yes, it did take a bit of force.

Even if I had headspace - I have none, European rifles are all checked for this before selling - the case would have been fireformed to exactly my chamber. But the extractor did not snap over it. As the bolt closed, this means the case was pushed forward = excessive headspace??? We are talking 1/2 mm or so, so I did not see any difference. Case usable or not?

Thanks for suggestions Hermann

As I said I will have the extractor polished, not relieved. So I see only advantages in that.

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Posts: 828 | Location: Europe | Registered: 13 June 2001Reply With Quote
<Vasa>
posted
The argument goes on, CRF and DGR, lots of armchair Bwanas. How many of you have ever faced anything where you had to shoot to save your life??

Listen to Ray - put that round into the magazine before chambering it, trust Mr.Mauser.

As for the the Rem700 extractor, somebody said something rude. That just about sums it up for push feeds. Try thick alders and costal Grizzlies!

Vasa

 
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aHunter
Not realy reading al the posts on this topic I might come up with answares already answared??!!!?...but anyway.

I take it that youre fired case was fired in you're "test" rifle , therefor I would roule out headspace problems on this case. (headspace problems in youre rifle however could be checked by a gunsmith in less than 2 minutes.

I think the unfired case of a 9,3X62 is more likley to be "resized" in youre chamber than for instance a 30-06 ,(because of the lesser shoulder area from witch it headspaces of.)
(The fellow with the 460 WM compress nothing as the 460WM headspaces of the belt...)


On CZ I have also found that the tip of the extractor ( the very point that touches the rim while sliding over the rim) , is sometimes sharp and while closing the bolt on a chambered round it "reams" out a small burr on the rim(this you should be able to see), sometimes the extractor is hooked on this burr and it will not fall down on the inside of the rim. (Most of the time the case still extracts slitly , maybe 5-10mm before the case falls of the extractor and remaind in the chamber,but it will at this point "poor" out of the rifle.)

In some cases one might even find a "thick rim".

It could also be a case of exessive lenghtwise play in youre extractor...or a combination of two or al four.

I would think youre cases are good to use , but do check out youre extractor , it's lenghtwise play etc.

PS , although I do not belive you have headspace problems , don't trust the pre-sale check of headspace, it might change(spoky), it might have been measured wrongfully/sloppy , besides the official proof test is for pressure not headspace...

PS II : To those of you who claims the feature of a military mauser that makes it not close on a chambered round is a divice for "counting rounds" does the military mausers bolt go forward on a empty magazine...

PS III: for those of you who think the rem700 has the best extractor in the world... Robgunbuilder & Mr.Atkinson = Amen.

S

 
Posts: 24 | Location: USA/Norway | Registered: 23 May 2002Reply With Quote
one of us
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Shadrek, you should read above posts. But thanks for your remark about pressing on the outside of the xtractor in another thread ...

No, no problem with that extractor, its tight and the cartridge slips easily under it. Extraction is positive, if I cycle quick the cases come out flying like on semi auto.

I have no headspace problem on the rifle. But if I "squeece" a fireformed case in the chamber, and the bolt closes, but the case stays in front of it ( the extractor did nor snap over the rim ) is now the rim damaged or the case shoved deeper into the chamber? This means with that case reloaded, there is less distance between case base and datum line. This problem is called "excessive headspace" IIRC? No? I can see no difference on the case, and now its hidden in the lot anyway.

Good shooting! Hermann

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Posts: 828 | Location: Europe | Registered: 13 June 2001Reply With Quote
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As a point of interest I have a copy of the 1928 W. J. Jeffery catalog. They produced two versions of the 98 Mauser bolt rifle in 333 and 404. One was a 5 shot magazine version, the other was a 3 shot magazine version (Model 3). The catalog states that the Model 3 could be loaded with 3 rounds in the magazine, and a 4th round could be inserted in the chamber and the bolt closed on it for a 4 round capacity. This (Model 3) was the model highly favored by John Taylor over the 5 shot magazine version due to superior handling qualities, so not every one believed that the snap over extractor was a bad thing.

The 5 shot mag version did not state that the same procedure could be done with it, so I decided to investigate further. As luck would have it I happen to have a 333 Jeffery made in 1908 (first year of production for this cartridge),and a Jeffery in 375 H&H made in 1951. I tried both rifles, and they both snap over the rim effortlessly and extract flawlessly. Obviously Jeffery made a habit of building rifles capable of snapping over the rim, and I think most will agree that this company had a good reputation for dangerous game rifles!!!

Good hunting,
Jim

 
Posts: 1206 | Location: Georgia | Registered: 21 July 2000Reply With Quote
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Hermann, in your particular circumstance I would say yes. The brass will give before any of the steel parts do, so if the extractor hasn't scraped over the rim, the it is pushing on the brass. If you can close the bolt on it, and you don'y have previous headspace problems, then you are probably pushing the shoulder of the brass back. Using the chamber as a re-sizing die, as it were. If you can isolate the brass and try some experiments with it (and some others, using a factory round as a baseline), I think you should be able to measure the brass and ascertain what exactly is going on. Hope this helps a little - Dan
 
Posts: 5284 | Location: Alberta | Registered: 05 October 2001Reply With Quote
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aHunter

A fireformed case should fit into the same chamber snuggly , and therefor from what you are telling me I would say that you are "resizing" youre empty case in the chamber, however I am somewhat puzzeled about the fact that you say that the case does not extract at al, because if the case is so "short" that the extractor does not snapp over the rim it would still extract the case by the sideways pressure of the extractor,that is if the extractor starts to "climb" over the rim....but if it is not,and the case is al in front of the extractor ,you would have to push the case almost 2mm forward in the chamber...and that would take a lot of effort.

Can you repeat the "test" and look at the case , see if there is any markes on the rim, burrs, scratches etc.

You are not totaly wrong about youre headspace deffinision , but the headspace is meassured within the guns chamber , from as you say a datum line to the bolt face. A "small" cartridge could give you the impression that there is a headspace problem but in a gun with correct headspace the problem would be on the count of this undersized cartridge, not actually a gun problem. You have to determine wether its a headpace problem within the gun or a undersized cartridge.

S

 
Posts: 24 | Location: USA/Norway | Registered: 23 May 2002Reply With Quote
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Let's look at the Mauser extractor system from a design standpoint. The Mauser extractor was designed to feed a cartridge up from the magazine. At a carefully pre-determined point in its travel the rim of the cartdridge is DESIGNED to slip under the extractor. As it travels into the chamber the cartridge rim will stop against the rim of the bolt face. The headspace is established by the shoulder of the cartridge or belt. This is HOW THE MAUSER ACTION WAS DESIGNED. IT WAS NOT DESIGNED TO ALLOW A CARTRIDGE TO BE FED INTO THE CHAMBER DIRECTLY.The reason why is if you force the cartridge into the chamber with the extractor what you are doing in fact is pushing the shoulder foreward and creating excess headspace.You will find that it is much more difficult to force a snap over with a belted cartridge as the belt offers more resistance than a cartridge shoulder. When pushed hard enough by the camming action of the bolt, the extractor is forced to move outwards against its retaining beveled ring ( stressing the collar) and MAY finally snap over the rim ( usually tearing a chunk out). This is extremely prevalent on belted cases. The extractor in some cases may not snap over the rim but stop/cock against the rim leading to a failure to extract. In the case of a snap over, if the rim is torn sufficiently, you may also have a failure to extract. The retaining groove bevel and the matching bevel of the extractor exert a combined force on extraction to facilitate the removal of stuck or dirty cases.
You can modify a Mauser to allow for a snap over by re-shaping the extractor and/or by finding an extractor with sufficient slop in it as compared to the beveled bolt retaining groove that allows the extractor to move outward sufficiently to slip over the rim of the chambered cartdridge.
In my experience some guns will allow for a snap over and some will not.Most frequently you can force the snap over to occur. This has been the subject of a couple of threads on this site.
It is clear that the Mauser action was not designed for a snap-over and I believe that this remains a bad idea. I have seen broken/damaged mauser extractors and distorted retaining collars and believe that this was probably owner induced by the unknowing practice of forcing snap overs. The beauty of the Mauser is that the design will not fail when used properly. You are of course free to do whatever you want!-Rob

[This message has been edited by Robgunbuilder (edited 02-28-2002).]

 
Posts: 6314 | Location: Las Vegas,NV | Registered: 10 January 2001Reply With Quote
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Coming in a little late here, and I don't have a Mauser or a CZ, but I see that the topic is about CRF, and my new Mod 70 is that.

My 375H&H not only easily closes over a round in the chamber, but the factory user manual states that it will do so, and recommends this as the way to make use of the rifle's capacity (3 in the mag, 1 in the chamber).

Rick.

 
Posts: 1099 | Location: Apex, NC, US | Registered: 09 November 2001Reply With Quote
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