Controlled-feed v. Push feed

[captain luke]

What is better and what is the big deal?

[TonyF]

The Controlled Round Feed (CRF) system is better.

The CRF is the original mauser design whereby the extractor snaps over the rim of the cartridge as the bolt strips the round out of the magazine and feeds it into the chamber. It eliminates the potential for "short-stroking" the bolt and causing a mis-feed.

This feature is critically important when hunting dangerous big game or using a bolt gun for self defense.

Currently, only Winchester (Model 70 reissue and classic and pre-64 featherweights), the Ruger M77 MKII and Hawkeye and Kimber offer the CRF system.

FN also offers the CRF but they only produce police and .mil precision systems.

[captain luke]

I read this in an article about the Ruger M77 Mark II and I'm kind of confused as to the differences between "claw extractor" and "Mauser style blade ejector" and "plunger ejector". I know this is probably beginner's stuff, but I am one.


"The claw extractor was retained, but the bolt face was opened up to allow controlled-round feeding. The plunger ejector was replaced with a Mauser style blade ejector"

[Tomcat088]

The Controlled Round Feed (CRF) system is better.

The CRF is the original mauser design whereby the extractor snaps over the rim of the cartridge as the bolt strips the round out of the magazine and feeds it into the chamber. It eliminates the potential for "short-stroking" the bolt and causing a mis-feed.

This feature is critically important when hunting dangerous big game or using a bolt gun for self defense.

Currently, only Winchester (Model 70 reissue and classic and pre-64 featherweights), the Ruger M77 MKII and Hawkeye and Kimber offer the CRF system.

FN also offers the CRF but they only produce police and .mil precision systems.

Great info here Tony, although there are a few things that I disagree with. I've NEVER seen a control feed system keep someone from short stroking a bolt. I was always taught that short stroking a bolt was not pulling it back far enough; short stroking to my understanding has never meant not closing a bolt fully. So if you don't pull the bolt far enough back, it doesn't matter if you're using a PF or CRF; the bolt will not pick up the next round because it doesn't go back far enough to pick up a round or let the extractor go over the rim.

I do agree though that when hunting dangerous game it would NEVER be a bad idea to have controlled round feeding. I've found that the main place that CRF makes any type of difference is when you're trying to cycle a bolt action rifle upside down or completely sideways. Most of the time even a Remington 700 won't have trouble cycling sideways, but they hang up sometimes, and the CRF does work better. Good luck getting a push feed rifle to cycle upside down, but the CRF can do it. Either way, these aren't the ways that I cycle a bolt action rifle, and I've never had cycling issues with any of my Remington 700's, especially if the feed ramps are polished.

As you stated, only the original Winchester model 70's have the CRF, there's lots of modern model 70's that don't have it. The Ruger 77 Mark II's do have CRF. I didn't know the Kimbers do, so thank you for letting me know. One thing that sometimes happens in my buddies pre 64 Winchester model 70 is that it likes to snag on the feed ramp. I think it's partially related to the fact that the bullet can't go anywhere because it's under the extractor; while with the Remington 700 it has a bit of wiggle room. It should be noted that I've seen it happen with push feed and controlled feed systems, that bullet can snag on the feed ramp; it's usually resolved with a good polish in both systems too. Oh and newer Winchester model 70's ARE FN's, they bought the patent for the action out when Winchester went bankrupt. There's no such thing as "Winchester" anymore, it's really just a division of FN; they just leave the FN name on their higher end tactical rifles.

Also, another point that should be mentioned about push feeds and controlled round feeds is the extractors. We're talking about extreme conditions, dangerous situations, hunting, etc. Have you ever tried to change the extractor out of a controlled round feed system in the field? Have you ever tried to change a Remington 700 extractor in the field? You can change a Remington 700 extractor in no time, good luck doing that to the controlled feed systems. Branches of the military have built rifles on CRF and PF systems, especially in the 70's. I don't know that it says much that most current tactical rifles are built on PF systems, just means that's what got chosen and so there's more options for those actions now. I think it boils down to that it's not really much of an advantage or disadvantage, more of a preference thing. As I stated before, I've found the main difference has to do with if you try to cycle the bolt while the rifle is upside down. Simplicity of form has it's advantages and disadvantages, just like complication can do some extra things, but also has it's draw backs.

[nhm90]

Keep in mind that the entire CZ centerfire line (527 and 550) is also based on the Mauser action with controlled round feed.

http://cz-usa.com/products/by-category/rifles/

[TonyF]

Great info here Tony, although there are a few things that I disagree with. I've NEVER seen a control feed system keep someone from short stroking a bolt. I was always taught that short stroking a bolt was not pulling it back far enough; short stroking to my understanding has never meant not closing a bolt fully. So if you don't pull the bolt far enough back, it doesn't matter if you're using a PF or CRF; the bolt will not pick up the next round because it doesn't go back far enough to pick up a round or let the extractor go over the rim.

Pay closer attention.

I stated short stroking the bolt can "cause" a mis-feed. I've seen on more than one occasion, a push feed get bound up by moving the round in the magazine ever so "slightly" until it gets hung up on the feed ramp. Did this myself once with my Rem 700.

As you stated, only the original Winchester model 70's have the CRF, there's lots of modern model 70's that don't have it.

Those would be the post 64 rifles. There were a few post 64 "classic featherweights" that were CRF.

The Ruger 77 Mark II's do have CRF. I didn't know the Kimbers do, so thank you for letting me know. One thing that sometimes happens in my buddies pre 64 Winchester model 70 is that it likes to snag on the feed ramp.

Might it be a .308? The pre 64 .308's were built on the long actions which means there is a quite a bit more bolt travel given the short length of the .308 winchester case.

Oh and newer Winchester model 70's ARE FN's, they bought the patent for the action out when Winchester went bankrupt. There's no such thing as "Winchester" anymore, it's really just a division of FN; they just leave the FN name on their higher end tactical rifles.

I know. FN has owned "Winchester" for quite a while.

Also, another point that should be mentioned about push feeds and controlled round feeds is the extractors. We're talking about extreme conditions, dangerous situations, hunting, etc. Have you ever tried to change the extractor out of a controlled round feed system in the field?

But that's the point. You won't have to because it's a very robust system.

Have you ever tried to change a Remington 700 extractor in the field? You can change a Remington 700 extractor in no time, good luck doing that to the controlled feed systems.

That depends on the vintage. Newer 700's do have a very easy field replaceable extractor. IIRC they basically just "pop" in. Not so the older 700's.

[TonyF]

I read this in an article about the Ruger M77 Mark II and I'm kind of confused as to the differences between "claw extractor" and "Mauser style blade ejector" and "plunger ejector". I know this is probably beginner's stuff, but I am one.

"The claw extractor was retained, but the bolt face was opened up to allow controlled-round feeding. The plunger ejector was replaced with a Mauser style blade ejector"

A blade ejector is not part of the bolt and is inset into the rear of the receiver. A plunger style ejector is a spring loaded plunger inset into the bolt face.

[Tomcat088]

Pay closer attention.

I stated short stroking the bolt can "cause" a mis-feed. I've seen on more than one occasion, a push feed get bound up by moving the round in the magazine ever so "slightly" until it gets hung up on the feed ramp. Did this myself once with my Rem 700.

I've never done this, although I'm sure it can happen. Just about anything can happen with a rifle when you need it to work. Then again, I don't short stroke bolts I run them all the way baby, lol. I'm just giving you hell, I guess I haven't been running them fast enough.

Might it be a .308? The pre 64 .308's were built on the long actions which means there is a quite a bit more bolt travel given the short length of the .308 winchester case.

No sir, it is not a .308. It's a .22-250 and definitely a short action, I promise

I know. FN has owned "Winchester" for quite a while.

I figured that you were aware of this, but threw it out there for the others watching that might not be aware of it. lol, I KNOW that you know.

But that's the point. You won't have to because it's a very robust system.

I know they're quite robust, but I've still seen some with extractors blown out. I've heard of it happening at matches too and people being completely screwed, where as the Remmy guys had theirs up and running. I've heard of it happening with some hot reloads, and sometimes didn't know the story. Either way, I assure you that they are sometimes blown out.

That depends on the vintage. Newer 700's do have a very easy field replaceable extractor. IIRC they basically just "pop" in. Not so the older 700's.

How old? My recent built rifle (the one that there are pictures here of) is built on a '64 ADL 7mm Mag action, and has the original bolt. It still has the "pop in" extractor in it that is field replaceable. I might have to go see what years they don't have it. As you know, neither systems ejectors or something that needs to be changed often, so I haven't checked too closely. I'll have to go look at some of dad's and see if he has any that have a different extractor. Neither of us owns one that's "newer" (90's or later).

[TonyF]

How old? My recent built rifle (the one that there are pictures here of) is built on a '64 ADL 7mm Mag action, and has the original bolt. It still has the "pop in" extractor in it that is field replaceable. I might have to go see what years they don't have it. As you know, neither systems ejectors or something that needs to be changed often, so I haven't checked too closely. I'll have to go look at some of dad's and see if he has any that have a different extractor. Neither of us owns one that's "newer" (90's or later).

Hmmm. I know Brownell's sells a tool to stake the Rem extractor cuz it's sort of riveted in place isn't it?

http://www.brownells.com/.aspx/pid=3..._EXTRACTOR_KIT

And the instructions indicate the old extractor needs to be drilled out. How do you that in the field?

http://www.brownells.com/userdocs/le...-562%20Rem.pdf

Are you sure about the vintage of the "pop in" cuz IIRC, the "pop in" extractor was a rather recent development (within the last 5 years or so).

[Tomcat088]

Hmmm. I know Brownell's sells a tool to stake the Rem extractor cuz it's sort of riveted in place isn't it?

http://www.brownells.com/.aspx/pid=3..._EXTRACTOR_KIT

And the instructions indicate the old extractor needs to be drilled out. How do you that in the field?

http://www.brownells.com/userdocs/le...-562%20Rem.pdf

Are you sure about the vintage of the "pop in" cuz IIRC, the "pop in" extractor was a rather recent development (within the last 5 years or so).

Hmm, to be honest, I'm not sure. They're not in the easiest place to see and I haven't had to change one on my rifles, and haven't looked super close. I'll have to go check it out. I've helped a friend change there's and you could get it out with a dental pick or a pocket knife if you held your tongue right. I'll have to go look at it, but if it's riveted in place then it would have to be drilled out. If that's the case, lol, I may be modding my soon. I appreciate this info, I'm not an expert on the Remington 700's, but I do know more than most people do about them. I'm gonna have to go look and get back to you, it's most likely riveted.