CRF vs Push Feed

[herb]

Took some photos of my .375's, one is a Remington XCR push feed & the other is a CZ550 Control Round Feed. The CZ is old world style - wood, blue and express sights. The Remington makes more sense to drag thru mud & snow as it is synthetic & stainless. Two really very different guns though both are .375 H&H.

The one on the left with the claw extractor is the CZ550, the plunger ejector can been seen on the Remington.










Herb

[The Doc]

Herb,

WOW !!
I really envy you mate. Personally I prefer the "old world" CZ but I'd never ever dream of dragging the Remmy through the mud and snow . I'd give it proper TLC I am sure .

Tell me which one do you enjoy shooting more and why ?

cheers,

RP.

[timmy]

Beautiful rifles, Herb! The Mauser action has always been the standard by which all other sporting rifles have been judged, and the Remington action has also been noted for strength and reliability since the first style of this kind saw the light of day as the 721, 722, and 725 models.

Many moons ago, I had a 721 in 300 H&H. I liked it, but it wasn't very much fun to carry with its 26" barrel.

Regarding the controlled vs push feed issue, as I understand it, the whole business was supposed to prevent double loading and a possible inadvertent discharge when the point of a second round's bullet was slammed into one already in the chamber, caused by battlefield nerves not closing the bolt fully on a push-fed chambered round. There are some things that make me wonder about this story, one being that the Germans didn't come out with a pointed spitzer-type bullet in 7.92 x 57 until 1905, after the M98 was introduced.

Another issue is that "controlled feeding" is not the only way to solve this problem. For instance, the Russian Mosin Nagant could be considered a "push feed" design, except that there is a controlled feed from the magazine provided by the interrupter. Until the bolt is closed sufficiently enough for the extractor to lock over the rim of a chambered round, the interrupter will no allow another round up to the top of the magazine. Thus, it is impossible to double-load a Mosin Nagant, even tho it is push feed. And, lest one object to the added complexity of the interrupter, I would note that it actually is a small tab that is part of the ejector (or ejector spring, in the second design), and the Mosin Nagant action is hardly something anyone would call complex or unreliable.

Nor do SMLEs seem to be plagued with double loading problems, either.

I will say that the small C clip extractor of the Remington design does have the occasional habit of tearing off a small chunk of the cartridge rim without retrieving the case, tho I'll readily admit that my loads on those occasions were a bit close to maximum.

I'm noting that the CZ does not split the left locking lug like the original M98, but instead follows the same practice as the old Model 70s.

Anyway, I cannot imagine that any of my long winded discussion touches upon anything that makes either of your fine rifles unsuitable for whatever you are using them for or makes either of them any less enjoyable to own, handle, and shoot. The 375 is quite the brass banana, whatever you are shooting it out of!

Thanks for sharing!

[MoA]

Personally I dont like CRF actions...
Simple reason being very often the most accurate COAL for a given rifle will not fit a magazine.
In which case you end up with a jam.

Then again the Vz I have is a CRF... then again I dont expect high accuracy with it.

[TwoRivers]

I would not call a rifle "noted for........and reliability", and then admit "the occasional habit of tearing off a small chunk of the cartridge rim without retrieving the case,". That hardly supports a claim of reliability. And, it can get you killed. The old chlorate primers of the 1880s were a lot more sensitive, and a lot less uniform than primers are today. Accidents did occur, but during training. The bullet after all, had a hard steel jacket, and not very blunt point; and yes, you can set off a primer with it. Germany adopted the "S" bullet in 1903. After all rifles in the hands of troops had been rechambered and resighted, the announcement was made in 1905.

The Nagant interruptor system cannot be applied to a magazine with staggered cartridge storage and feed.

The Lee-Enfield bolt controls the round as soon as it comes out of the magazine.

CRF does not require a long non-rotating extractor. Though that's the feature of the best known ones.

To MoA's reason for disliking CRF, if you don't get to fire that overlong round you snaked into the chamber of a push-feed, you get...a jam; and have to remove the bolt to get the unfired cartridge out. Remember, no repeater is designed to accept cartridges longer than will fit in the magazine. The M98 was designed to be only loaded from the magazine. At the cost of leaving about a third more cartridge out of the chamber, the 1903 Springfield, and the Winchester Model 70, allow chambering a round without using the magazine. The M98, can be single-loaded as well; but requires a little trick in the process. And it can be modified to do so without that. Last but not least, there is no correlation between the accuracy of a rifle and the kind of extractor it has. Cheers.

[lazybones]

Great pics Herb.

Ashok

[timmy]

I would not call a rifle "noted for........and reliability", and then admit "the occasional habit of tearing off a small chunk of the cartridge rim without retrieving the case,". That hardly supports a claim of reliability. And, it can get you killed.

I'm sorry, you must have missed the part where I said I was shooting hot hand loads when this problem occurred. Thankfully, I was never killed by a charging target, but have remained alive to make this clarification. I have always used factory ammunition to hunt large game. Besides, I have not hunted Jim Corbett's Panar leopard or Champawat tigress: Like many other hunters, I've never been in a life-threatening situation (beyond hypothermia). I feel that I'm the best person able to judge the suitability and choice of the firearms I use, and match them appropriately to the factors of the hunt I'm engaging in.

It seems to me that the best policy is to "admit" the whole truth and nothing but the truth regarding my experiences. If someone interprets the information I present differently than I do, I don't feel a need to correct them on matters of opinion or interpretation. Opinions on many web boards are often espoused with the fervent advocacy one normally associates with dogma. I'd like to avoid that practice -- I feel that it makes for a much more pleasant web experience.

The Nagant interruptor system cannot be applied to a magazine with staggered cartridge storage and feed.

This is true -- but I hope you are not implying that the staggered column magazine is the only suitable arrangement for a bolt rifle. I would not agree with such a position. Both the Colt-Sauer and the Schultz & Larsen rifles are known for being well made, high quality rifles that use single column magazines.

However, the reason I brought up the example of the Mosin Nagant was not to discuss single and double column magazines, but to illustrate a simple and reliable method that can be used with push feed systems that prevent double loading.

At the cost of leaving about a third more cartridge out of the chamber, the 1903 Springfield, and the Winchester Model 70, allow chambering a round without using the magazine.

The cone breech system of these rifles was not, I believe, an improvement over the M98 breeching system with the inner receiver ring. Wags have suggested that the best parts of the Springfield design were the ones copied from the M98, and the ones that were "improvements" turned out to be somewhat dubious in utility. Personally, one improvement I think that the Springfield offers over the M98 was in the bolt stop arrangement, which is very nice and trim compared to the M98. The Springfield's two-piece firing pin (a Krag hold-over) was not a good design, nor was the safety lug an improvement. I especially dislike the Springfield's slimmed-down bolt sleeve -- the M98 design (or, at least, the military and earlier commercial ones did until the "stylists" had their way) seals the back of the receiver in the event of a case failure. As someone who has had some cases let go on me while sitting behind a Springfield action and had my face and eyeglasses peppered with hot powder, I confess to being quite partial to the M98's gas handling arrangement as well as its more fully supported case. I feel that the big advantage the Springfield has over the M98 is that its receiver allows a better bedding in the stock.

The M98, can be single-loaded as well; but requires a little trick in the process. And it can be modified to do so without that.

If the modification you have in mind is that practice of grinding down the claw of the extractor sufficiently to allow it to snap over a chambered round within the confines of the inner receiver ring cut, I would have to observe that I hardly consider this a fix -- such a modification is hardly in keeping with the theme of reliability, or Mauser would have designed the weapon that way to begin with.

Nor do SMLEs seem to be plagued with double loading problems, either.

The Lee-Enfield bolt controls the round as soon as it comes out of the magazine.

You are right.

[z375]

To MoA's reason for disliking CRF, if you don't get to fire that overlong round you snaked into the chamber of a push-feed, you get...a jam; and have to remove the bolt to get the unfired cartridge out. Remember, no repeater is designed to accept cartridges longer than will fit in the magazine. The M98 was designed to be only loaded from the magazine. At the cost of leaving about a third more cartridge out of the chamber, the 1903 Springfield, and the Winchester Model 70, allow chambering a round without using the magazine. The M98, can be single-loaded as well; but requires a little trick in the process. And it can be modified to do so without that. Last but not least, there is no correlation between the accuracy of a rifle and the kind of extractor it has. Cheers.

Truer words ne'ver spoken, Two Rivers.

MoA - Its all well to not like a CRF action, but the chances of you getting mauled or stomped into a stain on the ground by a 100m paper target are nil, so considering the odds (if any) you're pretty safe......but when you've fallen on your back and there's a 10-foot Kodiak towering above you....you'll wish you'd have kept that tack-driving push-feed at home and taken a hunting rifle, buddy...

--

[MoA]

When I do go hunting for Kodiak, I will ensure I have an appropriate rifle. Until then, I will continue to shoot cartridges that do not fit in a magazine thank you very much.

While the action has little bearing on the accuracy of a rifle, the overall length of a cartridge does. Probably not in hunting environments, but more so in target shooting.
Cheers.

[TwoRivers]

Timmy: No, I did not miss the part about you shooting hot handloads, i.e. you being somewhat reckless in your handloading. But, having only your admission to that fact, and having no further knowledge of the matter, or how hot your handloads were, above proof pressure?, I let it go without further comment. Especially since I know that the Remington 721/700 can and will do that with factory ammo and about 10 rounds fired in about five minutes. Why do you think there are at least two different "Sako" extractors on the market to replace the original? Further, Remington has paid out millions because of safety/trigger failures. Reliable?, not by my standards.

So you were charged by a target but got away without being killed? Good! (Clever retort, by the way!)
That would be the first reported instance of that happening. Soldiers tend to shoot at each other; and big critters with claws and teeth have a tendency to put them to use after being annoyed and hurt.
Which brings us to the crux, so to speak. Target shooters entering the CRF vs. push-feed debate, and voicing opinions on a military requirement, which also is vital to big/dangerous game hunters; which does not concern them at all, and therefore do not comprehend. More than just for the prevention of double loading, CRF prevents the cartridge from falling to the ground, or rolling into the left lug raceway, if the rifle is not horizontal, and canted during reloading. In war,or during the hunt, you may be running while repeating, and the rifle is frequently held in a "port" position. The fact that Mauser had patented a CR device prior to the development of the long external extractor, that Nagant and Dauteau developed interruptors, that with exception of the M36 MAS, plus the M88 and the pre-M93 Mausers, all military rifles developed during that period are CRF; should tell us that it was an important requirement for the military everywhere. The paperpuncher does not encounter any conditions that would make him appreciate CRF. He doesn't need it. Neither does the varmint shooter.

Don't see your implication concerning staggered vs. single column magazines. Again, a requirement to have a minimum of five cartridges in an enclosed, non-protruding magazine. As a matter of fact, the designer would have to be totally incompetent to come up with a single column magazine that is not a partial CRF. It is interesting that you should mention the Schultz and Larsen's single column magazine, as that was one of the few that didn't function well, and was changed to a staggered magazine after three years. Which also left much to be desired. The follower of the single-stack only supported the cartridge about halfway up its middle, which meant that the rear of the last cartridge in the magazine could, and with great regularity would do so, tip down below the bolt and would be over-ridden. If you only need 2-3 rounds in your rifle, those single-stacks are fine and dandy. But if you drop the magazine on the rocks, or it falls out of your pocket without you noticing, than you have a single shot. Any weapons design is a compromise, and balancing of desired features.

No, I wouldn't dream of simply grinding back a Mauser extractor until it snaps over the rim during single loading. No, that modification involves reshaping the extractor nose and modifying the breech face for the needed clearance. Only ever did one for a customer who absolutely insisted on having six rounds in his Mauser, and was willing to pay for it. He could just as easily have bought a pre-64 M70 Winchester instead. But he loved his custom 98, except for the fact that he couldn't single-load. Not a very confident, or good shot, I guess.

That neat bolt stop of the Springfield was the unintended result of our military requiring a magazine cut-off. But it also comes at a price. It has a much smaller contact area than the 98's, and will batter the lug with much use. It also makes for an ejector that can through wear no longer make contact with the cartridge base. Last, in my opinion, the more symmetrical receiver of the 98 is easier to stock than the Springfield's. But that's just an opinion. Cheers.

[timmy]

TwoRivers:

No, I wouldn't dream of simply grinding back a Mauser extractor until it snaps over the rim during single loading. No, that modification involves reshaping the extractor nose and modifying the breech face for the needed clearance.

I am finding your modification that allows the extractor claw of a M98 Mauser to snap over the rim of a chambered cartridge curious. From your description, I don't understand just what your modifications accomplish.

The breech face of an M98 Mauser barrel is totally flat and perpendicular to the bore axis, and the extractor claw does not need or have any cut of the breech face of the barrel to allow for clearance to the extractor. Would you please describe exactly what reshaping you do to the extractor claw that requires removal of material from the flat breech face of the barrel?

That neat bolt stop of the Springfield was the unintended result of our military requiring a magazine cut-off. But it also comes at a price. It has a much smaller contact area than the 98's, and will batter the lug with much use.

Of course if functions as a magazine cutoff as well. But I cannot accept your assessment that its smaller surface area causes the back of the locking lug to wear anymore than it does in the M98 design. I know that you are an expert on the Pre-64 Model 70 Winchester and I'm curious as to how you see the bolt stop of the Springfield M03 comparing to the M70's in this regard. For instance, I'd be interested in your take of the surface area of the thin piece of metal that serves as the M70's bolt stop and the utility of the small diameter trigger pin it pivots on in accepting the force of the bolt slamming back, compared to the way that the bolt stop of the Springfield is anchored in the receiver.

Timmy: No, I did not miss the part about you shooting hot handloads, i.e. you being somewhat reckless in your handloading. But, having only your admission to that fact, and having no further knowledge of the matter, or how hot your handloads were, above proof pressure?, I let it go without further comment.

TwoRivers, my reload data for my 300 H&H 721 Remington was taken from the Sierra Manual copyrighted 1971, from page 171 of that manual, where it lists the max load for the 165gr HPBT as being 74.8gr of 4831. I also note that Sierra lists the test rifle for these loads as being a 721 Remington, just like my rifle.

After judging me "somewhat reckless" for using this data, I am thankful that you dropped your judgments of me "without further comment," for I would have hated to hear what additional things might be added to the charge of being "somewhat reckless" with my handloading. I can't tell you whether my loads were above proof pressure or not, but I seriously doubt that they were. Like most handloaders, I do rely on my handloading manuals. However, If I'm ever up in Alaska, I'd certainly appreciate the offer to test my handloads on the pressure testing crusher you are using to test your handloads -- that would be an interesting experience.

Further, Remington has paid out millions because of safety/trigger failures. Reliable?, not by my standards.

I appreciate the fact that you are not impressed with the Remington 700 design as a rifle to use for hunting dangerous game (or any game at all?). However, the information you relate doesn't match my own or that of others I know who have used these weapons, nor does it match the impressions passed along by other gun writers, some of whom are quite respectable (like Frank De Hass).

I'd also mention that your standards regarding the M700 Remington don't seem to be shared by the US Army or the US Marines, as the M700 was the issue sniper rifle in Vietnam and derivatives of that rifle continue to be used by the US Army as the M24 and the US Marines as the M40. Do you perhaps see sniper duty as being more akin to paperpunching than to hunting dangerous game?

[TwoRivers]

Tim:
It's difficult to understand things if we don't want to. You build up the extractor claw so it is thicker, then taper the front edge so that it can snap over the rim, just like the Model 70's. Then you provide clearance for the added thickness.

Yes, it would seem that the thin bolt stop of the M70 (and the 700) would be inadequate, but they don't get "slammed" like a military rifle hundreds of recruits train with. Obviously they picked the right material and heat treatment. The nickel steels Springfield bolt are they only ones that will show visible signs of battering from the bolt stop.

Using a reloading manual is not reckless. But note the instruction to work up to a maximum load from 10% below? What makes you think data gained from another rifle, with components from 1970, or before, will give the same results in your rifle? I don't use a copper crusher to test my handloads, I just use common sense in developing them. Remington's standard may be lower, but a rifle is supposed to fire and extract a blue pill without damage.

You must know even more about Model 70s to declare me an expert, as I don't claim to be that. You see, I hardly ever get to see them. Now, Remington M721-700s, that's another story. I get to see them with fair regularity. Even have a jig for them to put bolt handles back on.

Yes, Frank De Haas was one of the better writers, though there are errors in his writings. I base my opinion not on what some writer has to say, but on my own experience, and some 47 years of working on these guns. The M700 is accurate, the shiny finish appeals to some, and if you don't have to rely on it for your life, it's a fine gun. Just don't pull the trigger with the safety on, and then release it, because you may be the lucky person whose M700 will then fire. If you hit someone, it's at least five million from Remington. Or let the chamber get a bit dirty. A wilderness rifle it is not.

Snipers work in teams, with the spotter being armed with the standard issue rifle, or an M14, and at long range, from a hide. Still the military's choice is not one I would have made. But then, our military hasn't exactly set a shining example for adopting reliable weapons, or even picking a twist that would stabilize the bullet chosen. As they say, "military intelligence" is an oxymoron. Cheers.

[timmy]

TwoRivers:

You build up the extractor claw so it is thicker, then taper the front edge so that it can snap over the rim, just like the Model 70's. Then you provide clearance for the added thickness.

When the extractor is such a close fit in the right locking lug raceway and the front part of the extractor is in the part of the inner receiver ring that has been broached to the same size and depth as the right locking lug raceway, where does the extractor find the room to move enough to the right to snap over the case rim?

Yes, it would seem that the thin bolt stop of the M70 (and the 700) would be inadequate, but they don't get "slammed" like a military rifle hundreds of recruits train with. Obviously they picked the right material and heat treatment. The nickel steels Springfield bolt are they only ones that will show visible signs of battering from the bolt stop.

Ah, I see, so your complaint about the Springfield bolt stop is not its design, but only pertains to the nickel actions, not the single or double heat treat ones, and then only the actions in military service, not when the action is used for hunting deadly game (which is what I thought you always referred to). Now I understand. I had thought that your objections to various actions were always based on the perspective of their design and suitability for hunting dangerous game.

Using a reloading manual is not reckless.

Whew! I'm glad I'm back to not being reckless!

But note the instruction to work up to a maximum load from 10% below? What makes you think data gained from another rifle, with components from 1970, or before, will give the same results in your rifle?

Well, TwoRivers, you must be some kind of an expert to assume that I did not work up my loads from 10% as any manual will tell you to do when you know so little about me, don't you think? It is from statements like this, where you infer a knowledge about me that you cannot have, from which I draw the conclusion that you consider yourself an expert.

However, your expertise has hit another snag, since I owned the Remington 721 in the early 80s and the Sierra Manual that I used was then the current volume from that company. And, my components were, in some cases, even older. I am surprised to find out that you didn't know that 4831 powder from Hodgdon was all surplus powder and clearly marked so on the cans, and that this is what people shot at the time...

When you make a statement like: "What makes you think data gained from another rifle, with components from 1970, or before, will give the same results in your rifle?", I wonder then what rationale you offer for using any reloading manual data in any of your own firearms without doing your own pressure testing?

You must know even more about Model 70s to declare me an expert, as I don't claim to be that. You see, I hardly ever get to see them.

Since your observations were always made from the perspective of hunting dangerous game far from any signs of civilization, and that a M70 was the only suitable weapon for that kind of hunting, and that your observations were all based on your extensive experience, it seemed reasonable to infer that this was the kind of hunting that you did, and that the M70 was your trusted companion on all of your forays. Evidently, I erred on these points.

Snipers work in teams, with the spotter being armed with the standard issue rifle, or an M14, and at long range, from a hide. Still the military's choice is not one I would have made. But then, our military hasn't exactly set a shining example for adopting reliable weapons, or even picking a twist that would stabilize the bullet chosen. As they say, "military intelligence" is an oxymoron.

This is as weak of a dismissive argument as I've heard in many a moon. To question my judgment, as you have repeatedly done, based on the knowledge you have on what I've done is one thing. To give unworkable descriptions of how M98 extractor claws are modified to snap over chambered cartridges is another thing. But to set yourself up as an expert over the Army and Marines by questioning their intelligence by using hackneyed statements such as "As they say, "military intelligence" is an oxymoron." does claim for yourself the expertise to judge them and find them wanting, along with insulting the intelligence of a great many people who truly do know something and who do have a great deal of real experience.

I'll not trouble you further on this account; I've ascended your mountain and obtained enough data to sufficiently understand the situation.

[TwoRivers]

Timmy: To quote the prophet Mohammed "Speak to each man according to his understanding". Since you keep inferring things out of the blue, I'm beginning to see that in this case, that's impossible. We have gone off course far enough on this thread, my apology to the moderators, and thanks for their indulgence. Just in passing, I served in the U.S. Army, and used and worked on the equipment. Have you?

[lazybones]

Herb/Timmy/MoA/TwoRivers:

Thank you all for one of the most instructive set of posts I have read in a long time. This has been a real insight into the issues of a subject I've been interested in for a long time, but never got around to investigating. Thanks again.

Ashok