Just wondering what opinions were of controlled feeding in big bores. My brnu 375 h&h has a controlled feed, the only one of my rifles with this design. I have heard that it is more reliable, but I had a cartridge stick in the chamber at the range when I (after swithching between several rifles) mistakingly threw the round directly into the chamber and followed up with the bolt, which of course, didn't close. I didn't have the necesary tools with me to dislodge the round, and had to use the antena of my buddies truck. thankfully nobody was looking.
I figured this could be a significant issue if something with teeth were invovled. Any thoughts...

You can modify the extractor slightly to allow it to snap over a round thrown in the chamber.

quote:

Originally posted by BCJames:
I (after swithching between several rifles) mistakingly threw the round directly into the chamber and followed up with the bolt, which of course, didn't close.

That is the way the Mauser 98 is designed. You can thumb the extractor a bit to get it to slip over the case head, or as fredj338 mentioned, modify the extractor.

George

CRF is a very real issue to those that have been there and done it....(DG hunting)

I haven't but have been shooting centerfire rifles for 45 years and can honestly say that if I had to go after a Cape Buffalo with a pushfeed .375 H&H I'd be going regardless.

If one don't have a gun and is thinking about buying or making one I think it's prudent to listen to the overwhelming chorus of those that have been there and done that.

quote:

Originally posted by fredj338:
You can modify the extractor slightly to allow it to snap over a round thrown in the chamber.

Does this effectively turn a controlled feed into a pushfeed? Or are the benefits of a controlled feed retained?

Control round feed, push round feed, m-16 style extractor, mauser claw extractor, etc. etc. etc. It boils down to personal choices. The c.r.f. has its atributes and also has its problems, everything must be right or you will wind up with a jammed rifle and usualy at a very bad time, if your luck runs like mine. P.R.F. has been around about as long as any and seems not to have any more problems or good points than any other type of magazine feeding system. I think its all about confidence in what you are carrying around when you hunt the big stuff. Wbys's have a p.r.f. system and i have yet to see one jam if cycled corectly, but thats just me and i am sure some one has short cycled the p.r.f. system and put the rifle out of battery, this is its short coming. Pratice with the rifle you intend to use is paramont and i cant stress it enough. Shoot it and shoot it some more standing and cyclying the bolt and not taking it off of your shoulder , or your eyes off of the animal in your sights. Make sure it feeds without a hitch evry time, hunts are too expensive and life is too short, or bite the bullet break out the American express card buy a double and all this is a moot point. Charlie

quote:

Originally posted by BCJames:

quote:

Originally posted by fredj338:
You can modify the extractor slightly to allow it to snap over a round thrown in the chamber.

Does this effectively turn a controlled feed into a pushfeed? Or are the benefits of a controlled feed retained?

The benefits are retained.

Do rounds from a controlled feed rifle get loose and ahead of the extractor? If this is possible wouldn't a non controlled be more reliable, assuming that both will pull a round from the chamber?

quote:

Originally posted by 348srfun:
Do rounds from a controlled feed rifle get loose and ahead of the extractor?

No, in a true CRF, the round is controlled as it is stripped from the magazine.

George

quote:

Originally posted by vapodog:

quote:

Originally posted by BCJames:

quote:

Originally posted by fredj338:
You can modify the extractor slightly to allow it to snap over a round thrown in the chamber.

Does this effectively turn a controlled feed into a pushfeed? Or are the benefits of a controlled feed retained?

The benefits are retained.

So this would imply that modifying the extractor in c.r.f would be the way to go. True?

The modification is simple and any competent gunsmith can do it, if any modification is necessary at all. (Many CRF bolt rifles will be okay right out of the box.)

The outer face of the extractor claw is polished and beveled, to the minimum extent necessary, so as to remove the sharp edges and slightly reshape its surface angles.

This allows one to close the bolt on a cartridge pushed into the chamber over a fully loaded magazine (or otherwise, for that matter). The extractor claw simply slides and flexes over the the base of the cartridge and into the extractor groove.

All of my CRF dangerous game bolt rifles (CZs and M70s) permit this. I have a 100+ year old Model 1898 Mauser actioned rifle that does not permit this, but it is not a DGR.

quote:

Originally posted by BCJames:
Just wondering what opinions were of controlled feeding in big bores. My brnu 375 h&h has a controlled feed, the only one of my rifles with this design. I have heard that it is more reliable, but I had a cartridge stick in the chamber at the range when I (after swithching between several rifles) mistakingly threw the round directly into the chamber and followed up with the bolt, which of course, didn't close. I didn't have the necesary tools with me to dislodge the round, and had to use the antena of my buddies truck. thankfully nobody was looking.
I figured this could be a significant issue if something with teeth were invovled. Any thoughts...

Yes. CRF rifles are much safer for use on dangerous game!!

This "malfunction" you had is NOT due to the design or the operation of the rifle, but to your unfamiliarity with the fact that you cannot drop a round in the chamber and close the bolt on it UNLESS you push in on extractor about 1/2 of the distance back from the bolt head as you close the bolt and allow the extractor claw to slip over the rim and into the extractor groove. Trying to strong-arm the bolt closed on a round like you did just makes it worse, and is TOTALLY UNNECESSARY! Mauser type rifles are designed to let you pop the extractor claw over the case rim by pushing in on the rear half of the extractor. Mauser extractors are intended to operate this way without altering the extractor claw. I suspect, if anyone where you were shooting had known how a Mauser extractor operates, you could have closed the nbolt, fired that round, and gone merrily on your way to finish the day's shooting! No tools needed!!



An altered claw is acceptable on a non-dangerous game rifle, but NOT on a .375!!

Altered (properly altered!!) extractor claws won't affect the way the extractor functions, it just permits the bolt to close without having to push in on the extractor as you close the bolt. BUT, since the alteration does entail removing some metal from the extractor hook, it is NOT RECOMMENDED for a true DGR!

That's the best 'out' I've ever seen, including pictures, for the 'CRF'...but what makes the .375 exempt?
Nice post, BTW!

A proper CRF eliminates the possibility of a double feed caused by operator error. Only one cartridge can be in motion at a time.

Push feeding a round into the chamber, without pinching the extractor, will hammer the cartridge in place and require it to be rodded out from the muzzle. As stated above, this condition is caused by operator error.

Modifying the extractor to snap over the rim does not usually effect the CRF properties. However, it weakens the claw and may effect extraction properties, which are just as important if the rifle is to be used on dangerous game.

quote:

Originally posted by BusMaster007:
That's the best 'out' I've ever seen, including pictures, for the 'CRF'...but what makes the .375 exempt?
Nice post, BTW!

The 375 is not exempt as stated.....CRF is CRF period and for all cartridges. All of mine allow the bolt to close on a round hand placed in the chamber. Either they was made that way from the manufacturer or they was altered to do so. IMO it does not reduce the suitability of a rifle to alter the extractor to close on a hand fed round.

quote:

Originally posted by vapodog:
The 375 is not exempt as stated.....CRF is CRF period and for all cartridges. All of mine allow the bolt to close on a round hand placed in the chamber. Either they was made that way from the manufacturer or they was altered to do so. IMO it does not reduce the suitability of a rifle to alter the extractor to close on a hand fed round.

I agree, with the caveat that the hook alteration be done properly, ie., by a person familiar with and experienced in performing the alteration.....

When closing the action on a loaded CRF rifle that's properly working the cartridge is grabbed/held by the boltface and extractor claw as soon as it pops free of the magazine lips. It is then "held" in place as the bolt is closed and until the bolt is turned down and locked into place.

On a push feed action the cartridge is simply laying there loose ahead of the bolt face once the round pops free of the magazine lips. As you move the bolt forward the round is shoved ahead of it and then into the chamber until the bolt closes down and then holds it in place for firing.

On a CRF rifle, if you stop or alter the cycling of the bolt midway thru the stroke the cartridge remains held firmly to the bolt face - you can move the bolt backward or forward and the round stays attached to the bolt face until you FULLY draw the bolt all the way to the rear of it's stroke, at which time the round will be ejected from the rifle. At this point simply working the bolt forward again will feed out and grasp the next round in the magazine and guide it into the chamber.

On a push feed rifle if you interrupt that forward movement of the bolt the round is just laying there loose in the ejection port/action. If you're standing level that's not necessarily the end of the world as long as you complete the forward movement and closeing of the bolt and DON'T fully draw the bolt back. If you do draw the bolt back all the way, then you've now got the first round laying loose in the magazine and the next round in the magazine will be fed out by forward movement of the bolt - giving you TWO rounds in the action both of which are loose and uncontrolled. In this situation one of them will end up in the chamber perhaps but the other will jam up the bolt and prevent it from being closed. Is this occurrence rare? Yes it definitely is... Is it utterly impossible? No, not under unusual or stressful circumstances.

quote:

Originally posted by KurtC:
A proper CRF eliminates the possibility of a double feed caused by operator error. Only one cartridge can be in motion at a time.

Push feeding a round into the chamber, without pinching the extractor, will hammer the cartridge in place and require it to be rodded out from the muzzle. As stated above, this condition is caused by operator error.

Modifying the extractor to snap over the rim does not usually effect the CRF properties. However, it weakens the claw and may effect extraction properties, which are just as important if the rifle is to be used on dangerous game.

If the chamber is cut competently it should not be possible to "hammer the round into the chamber" because the Belt should stop it.
this is one of the original reasons for the belt to be there.

If it is possible to do so with your ammunition in your rifle you should try different (newer) brass, a different brand of brass, use fireformed brass that actually headspaced on the shoulder or have the barrel turned back and rechambered.

that is a condition that should not be tolerated, because it indicates a situation where the rifle is actually headspacing on the
claw face of the extractor rather than on the forward shoulder of the belt cut in the chamber
or on the case shoulder.

It should not be possible to push the round into the chamber sufficiently so that it sticks with only the motion of the bolt even with a non-beveled extractor.

If the front face of the extractor is properly beveled it will snap over the rim with a minimum of fuss.

From what I've seen very few older mauser type actions do not have this strategically placed bevel.

If you are worried about round getting "hammered into the chamber" to the point that the extractor cannot snap over it
and subsequently extract that cartridge then there is something very wrong with that rifle.

And BTW, if you haven't thought this through
that "one round" dropped into the chamber is only likely to be a scenario you'd encounter when loading up the rifle to maximize capacity by squeezing an extra round into the rifle and you'll KNOW that the rifle was jammed before you actually entered the dangerous situation.

I can't buy that in a "charge situation" that anyone other than superman could cycle the rifle through all the available rounds before the situation had concluded itself.

In how many charge situations does anyone get off a third round let alone a fourth with a bolt rifle?

Besides if you are the kind of idiot that goes into a potentially dangerous situation with ammunition that has not been trial fitted into the chamber well before hand (Yes, each and every round) then you probably deserve to be bit, scratched or stomped to pound that important lesson home.

Remember that any moron can learn from his own mistakes.
Intelligence is learning from the mistakes of others.

as far as a double feed in a non-CRF action
In 25 years of firearms handling I've never done this with a bolt action rifle when I wasn't intentionally doing it to demonstrate to someone how it COULD happen.
Even when dangerous game hunting I think you are in greater danger from failing to make sure that a scorpion hasn't taken up residence in your boots while you were sleeping than you would be from using a non-CRF rifle. Granted I'd rather have a CRF rifle because it's one less thing to be worried about when there are a sufficiency of things to be worried about, but.... I'd use the rifle I had if it was NON-CRF

Just because I can't afford a hunting trip to Africa doesn't mean I would love to go...

AllanD

quote:

Originally posted by 458RugerNo1:
When closing the action on a loaded CRF rifle that's properly working the cartridge is grabbed/held by the boltface and extractor claw as soon as it pops free of the magazine lips. It is then "held" in place as the bolt is closed and until the bolt is turned down and locked into place.

Correct. Moreover, as soon as it pops free of the mag it is to be under firm control of the extractor; firm enough such that reversing the bolt at that point (because of, say, short-stroke panic) would allow the round drawn backwith the bolt to be ejected from the action, and then a fresh can be fed from the mag - thus avoiding the dreaded double feed.

NOW, consider how many factory CRF rifles ACTUALLY function exactly this way. In my experience, a large percentage (you name the brand) have ill-machined mag-to-extractor exchanges that effectively undermine the main advantage of CRF - namely short stroke / double feed prevention.

Moreover still, I've found that some fixed blade extractor have overly weak springs and thus do not pop into the bolt face when cycling very fast. I've found this to particularly true of the pre-64 model 70...

Moral of the story. CRF is great, but it needs to be gone over by a VERY talented smith before being deemed a DG rifle (IMO)... (Perhaps the high end stuff like Dakotas are exceptions...)

quote:

On a push feed rifle if you interrupt that forward movement of the bolt the round is just laying there loose in the ejection port/action. If you're standing level that's not necessarily the end of the world as long as you complete the forward movement and closeing of the bolt and DON'T fully draw the bolt back. If you do draw the bolt back all the way, then you've now got the first round laying loose in the magazine and the next round in the magazine will be fed out by forward movement of the bolt - giving you TWO rounds in the action both of which are loose and uncontrolled. In this situation one of them will end up in the chamber perhaps but the other will jam up the bolt and prevent it from being closed. Is this occurrence rare? Yes it definitely is... Is it utterly impossible? No, not under unusual or stressful circumstances.

This is very good explanation of how short stroking / double feeding can occur in a PF. However, I think its frequency is directly proportional to the panic of the user, a fact P. P. Mauser knew well when designing his actions...

Take a PF pump shot gun. Think how often a double feed occurs when shooting clay doubles? Now triple that, and then you've got a good estimate of the probability you'll short stroke a PF when mbogo is up for a double...

Given the CRF is better for DG, it certainly isn't fool proof.

The much vaunted ability to eject a round if short stroking the bolt is great, unless it was your last one in the mag. NOT good.
If you short stroked with a PF, and realise it, one could tip out the loose round. If it's your last, no problem. (not counting Beasties running around.)


On AR, at least one member was complaining of his CRF working like a PF.

A friend of mine believes that SOME mausers don't have room in the action for the extractor to be "bent" over a chambered round ???

My .458 W. is over 1" into the action when it jumps out of the mag. , not that that makes it dependable.

And NO, I've never had to work a bolt in a tight situation, it's just that Allan D. got me to thinking. Hell, I'm sure I can run faster without a rifle, heck I was going so fast one day I had no hope of dodgeing, and this crazed beastie was just about on me, so I stuck my arm out and grabed a thin tree going by, spun out of the way just in time.

Two doubles is the way to go, with a man to hand and load the 2nd.
Just my Two Bobs worth.

quote:

The much vaunted ability to eject a round if short stroking the bolt is great, unless it was your last one in the mag. NOT good.

Yes, indeed. Very not good.

A 9.3x62 or x66 will serve you well there (better than a 375)... lots more short stroking before you run out of ammo...

Yes this is very common with my clients when i gave them one of my czs or mausers ,do you remember afrikaander ,i dont have push feeders and most of my clients are trained with them so this accident is quite frequent,and i happened one time in the middle of a swamp with a buffalo charging do you remember Steve .Juan

The last factory CRF rilfes ever made left Oberndorf in '45, Brno in '55, Belgium around 1965, and Steyr in 1969.

The current CZ comes close. Rugers and Winchesters have deviated too far from the original CRF design to even be considered. Don't be fooled by advertising that reads "mauser type" extractor. If you feel you need CRF, get the real thing.

PS - I use belts on my trousers, not on my cartridges.

Not to hijack the thread but I am curious how many professionals worry about the CRF feature. I have seen several PHs with Remington 416 and 375 model 700s in Zimbabwe. Cotton Gordon used a push feed model 70 458 in Tanzania. In Alaska I have also seen several 416 Remintons used by brown bear guides. There the emphasis seems more on synthetic and stainless than anything else.

perhaps this will clear the issue
CRF means that when the round is stripped out of the mag, it is fully under positive mechanial control. this has nothing to do with the ability to circumvent feeding from the mag.

if one able to load a round directly into the chamber, and have the extractor pop over, then this is not a characteristic that excludes CRF.

BUT if the round is not under MECHANICAL controlas it leaves the mag and then the chamber it's not CRF...

jeffe

KurtC,

"The last factory CRF rilfes ever made left Oberndorf in '45, Brno in '55, Belgium around 1965, and Steyr in 1969.

The current CZ comes close. Rugers and Winchesters have deviated too far from the original CRF design to even be considered. Don't be fooled by advertising that reads "mauser type" extractor. If you feel you need CRF, get the real thing."

Kurt,

I've checked my .375 RSM specifically for this - to verify that the round is held and firmly under the control of the boltface once it pops free of the magazine lips. From all I can tell it is. I can work the bolt forward or back and the round stays right where it should. If I drew the bolt all the way back obviously it's ejected, but that round stays firmly held to the bolt otherwise. I'm open to learn something new every day so please elaborate if I'm missing something ref your statement that most if not all modern bolt guns are not true CRF?

quote:

Originally posted by KurtC:
The last factory CRF rilfes ever made left Oberndorf in '45, Brno in '55, Belgium around 1965, and Steyr in 1969.

and in the CD as of 2 months ago, and today with a remington lable...

and Rock Island in 1948, ... and Remington again in the 50's with the enfields.

or, to express it a little better...

all mauser 98s were CRF, but not all CRFs are mauser 98s

458RugerNo1

My comment sarcasticly implies that the Rugers and Winchesters are hit or miss. Many of them only feed CRF from one side, mostly due to the one-size-fits-all posture of their magazine boxes and followers. True Mausers and Mannlichers have specific boxes, followers and rails for each cartridge, ensuring flawless feeding.

I also find the lack of a self-locking extractor on the Winchester, Rugers and Springfields to be an insult to the Mauser design. If you are going to copy someone, copy them properly. Not half-assed.

Jeffeosso,

Thanks for catching me on that one. I completely forgot that CD had resurrected the Belgium pattern. I don't have any experience with them personally, but I give them and Interarms credit for trying to do things properly.

quote:

Originally posted by LJS:
how many professionals worry about the CRF feature. .

LJS, all I know is what I've read on AR, and from that I gather any problems with PF s can be allowed for. A PH would consider himself able to do this, even under pressure.
From memory some problems discussed were;

Cartridges can/will fall out during feeding if the rifle is tipped or upside down.
Fix; If your spinning thru the air, don't load/reload until your upright.

The dreaded bolt shuffle;
Fix; Pull the bolt all the way back, then push it all the way forward.

Running with the action open;
Fix; Close the action or hold thumb over mag.

Also I suppose a PH may perhaps realise that of all the problems faced each day, the problems of a PF are just the ones he can control for sure. (As opposed to standing on a Mamba or something.)

Kurtc,
your comments are kinda inaccurate, on decrying the new guns as not being this or that... just like remmington bolt handles, i am certain it happens, but the MAJORITY of them are as described.

so, sure there's exceptions.. and I've had 98's that wouldn't feed 8mm anymore.. (due to wear out, actually)

does that make ALL 98's non-crf?
jeffe

quote:

My comment sarcasticly implies that the Rugers and Winchesters are hit or miss. Many of them only feed CRF from one side...

This is exactly consistent with my experience with Winchesters, and especially Rugers. I'd expect the RSM to have a better rep than the standard 77...