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Old January 14, 2013, 01:58 PM   #51
1stmar
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Walt I'm not a metallurgist or a spring guru, but compressing springs linearly against themselves should extend their usable life. Additionally, if you have a fte or Ftf how do you know if the spring/guide rod is a contributing factor or not? Pretty tough to say, many argue that jmb didn't use or that they are not used in countless military firearms w/o issue, I do not dispute that, but for the countless others that do have reliability issues that go unexplained or unresolved how do you know this is not a contributing factor? I simple remove it from the equation.
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Old January 14, 2013, 03:30 PM   #52
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1stmar wrote
Quote:
but for the countless others that do have reliability issues that go unexplained or unresolved how do you know this is not a contributing factor?
Easily proved or disproved: did the installation of a FLGR fix the unexplained issues?

My bet...is that it didn't.
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Old January 14, 2013, 05:01 PM   #53
Walt Sherrill
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Quote:
Originally Posted by 1stmar
Walt I'm not a metallurgist or a spring guru, but compressing springs linearly against themselves should extend their usable life.
I'm sorry, but I don't understand what "compressing springs linearly against themselves" means. If you're arguing that keeping lateral movement of a recoil spring to a minimum will slow spring degradation, you may be right, but I've seen no technical articles or other evidence to support that claim. Spring life is more obviously affected by other things.
  • Compressing recoil springs to or near their design/compression limit, or keeping them compressed near their compression limit -- i.e., fully compressed -- will shorten their lives. Most recoil springs are close to fully compressed during a firing cycle, but some more than others. Recoil springs in most sub-compact guns are compressed more fully than in other guns, and they tend to have shortest lives.
This discussion has been MOSTLY about a FLGR's effect on accuracy and a little about it's positive effect on reliability. Mike38 argued for better accuracy, but I don't think he offered proof.

I added the underlining, below.

Quote:
Originally Posted by 1stmar
Additionally, if you have a fte or Ftf how do you know if the spring/guide rod is a contributing factor or not? Pretty tough to say, many argue that jmb didn't use or that they are not used in countless military firearms w/o issue, I do not dispute that, but for the countless others that do have reliability issues that go unexplained or unresolved how do you know this is not a contributing factor? I simple remove it from the equation.
Or add it to the equation...

I agree that claiming "JMB didn't do it" is not a convincing argument. But, a contrary argument that you should do something without fact-based justification is not convincing, either.

In answer to your "how do you know" question, I'd say, you don't know. The only way to properly answer that question is to use a single recoil spring in one gun until you have a consistent FTF or FTE problem and switch to the other style of guide rod to see if that fixes the problem. But, to be really sure, you'll have to repeat that test several times, to know you've got predictable results.

The fact that a gun problem is unresolved is not evidence that something not done -- using particular type of guide rode -- is going to be a part of the solution.

If the problem is unresolved it really just means that a sufficiently competent gun "mechanic" (gunsmith) hasn't dealt with the problem.


.

Last edited by Walt Sherrill; January 14, 2013 at 08:51 PM.
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Old January 14, 2013, 09:48 PM   #54
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The FLGR hardly adds enough weight to notice while preventing press checks and over complicating break down.
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Old January 15, 2013, 10:51 AM   #55
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Quote:
The FLGR hardly adds enough weight to notice while preventing press checks and over complicating break down.
I can press-check my Colt XSE, which has a FLGR.
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Old January 15, 2013, 11:02 PM   #56
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It adds a little weight up front otherwise nothing. The tungsten rods add enough to matter, probably 3 oz.
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Old January 15, 2013, 11:23 PM   #57
James K
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One thing the FLGR did was to give us the various firing pin block gadgets with all their problems.

A standard 1911 is almost impossible to make fire by dropping or driving it on the muzzle. The reason is that the slide moves backward, cushioning the blow so the firing pin inertia is absorbed and the firing pin won't creep forward and fire the gun. (The California tests are not real world - they are rigged to ban as many guns as possible.)

Those who have an interest in WWII pistols might have noticed that the Polish Radom has a two piece guide rod. The original design was for a one piece FLGR. But in testing, they found that the gun would fire if dropped on the muzzle, so they made the guide rod two piece to absorb the impact and prevent accidental firing.

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Old January 16, 2013, 11:10 AM   #58
Walt Sherrill
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Quote:
One thing the FLGR did was to give us the various firing pin block gadgets with all their problems.
Those FLGR were an industry-wide "innovation" that was applied to all handguns -- guns that had NEVER used FLGRs switched to FPBs, too.
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Old January 16, 2013, 11:36 AM   #59
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"One thing the FLGR did was to give us the various firing pin block gadgets with all their problems."
The Swartz was invented in !939,do you have references to that benighted
guide rod prior to that?
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Old January 17, 2013, 12:38 AM   #60
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The guns that switched did so because the CA testing was much more stringent that a simple drop test from a few feet. IIRC the gun is placed in an arm that slams it down on a steel plate, equivalent to being dropped from a three story building.

Yes, the Swartz safety pre-dates the FLGR, but it was never installed on military contract pistols and was dropped after WWII because it was considered unnecessary. It is my understanding, which may be wrong, that the Swartz safety was not to prevent firing pin creep if the gun was dropped on the muzzle, but to prevent accidental firing if a cocked or half-cocked gun was dropped on the hammer hard enough to break out the hammer notches and drive the hammer onto the firing pin.

Jim
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Old January 17, 2013, 08:01 AM   #61
polyphemus
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Whether the pistol falls on its hammer or its muzzle the Swartz prevents
firing pin travel unless the trigger is depressed.I think both the FL guide rod
and the Swartz block are unnecessary encumbrances I just don't see how one
brought about the other and that includes the series 80.
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Old January 18, 2013, 05:58 AM   #62
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Up Close

Quote:
A fluoroscope of a 1911 firing the first round,wonders never cease.
This is a very absorbing and instructive picture,the slide appears not to have
started to retract even though the bullet is almost out of the barr
Look closer. Your eyes deceive you. Look at the position of the link and the aliggnment of slide and frame at the rear. The slide and barrel have moved about .070-.075 inch...which is just about right relative to the bullet.

Quote:
As as I understand it, the fired bullet leaves the barrel when the slide has moved a mere fraction of an inch (1/10th of an inch or so).
Yep. That's why it's called "Short Recoil Operated." The slide recoils for a short distance and the bullet leaves the system. At the point of bullet exit, recoil ends, and all movement of both bullet and slide come from the momentum conserved during the time that they were both being accelerated.

Quote:
If so, the roll a FLGR plays must have to do with consistency of lockup when the slide is returned to battery.
Has no effect on "lockup."

Quote:
Whether the pistol falls on its hammer or its muzzle the Swartz preventsfiring pin travel unless the trigger is depressed.
The Swartz system operates off the grip safety. The Series 80 system operates off the trigger.
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Old January 18, 2013, 06:07 AM   #63
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We can argue till the thread is locked, but literally hundreds of thousands of reliable and match-grade accurate 1911s are out there without a FLGR, including a handful I've owned in 45 and 38.

Not buying the hype.

Not to say that I wouldn't buy a 1911 with a FLGR--I just don't see the point except making it a PITA to field strip.
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Old January 18, 2013, 07:27 AM   #64
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Re:Up close

Yes of course the Swartz works through the grip safety but unless you depress
the safety you can't pull the trigger,right?
My poor eyes deceive that's for sure,here's what I see Mr. Tuner,a)the horizontal ribs are still fully engaged.there's daylight at the rear and top but
not at the front.b)the barrel is fully tilted downward and no part of it seems to
protrude from the slide.c)the barrel link seems to be perpendicular to the barrel.What I don't see is where the barrel hood is no longer in contact with the
breech face.I know less about 1911's than you've forgotten and I don't think you've forgot much but I called this one as I saw it.
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Old January 18, 2013, 07:39 AM   #65
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re:

Quote:
Yes of course the Swartz works through the grip safety but unless you depressthe safety you can't pull the trigger,right?
That's irrelevant. The Swartz system still works off the grip safety. Depressing it will release the firing pin stop plunger, whether you pull the trigger or not.


Quote:
My poor eyes deceive that's for sure,here's what I see Mr. Tuner,a)the horizontal ribs are still fully engaged.there's daylight at the rear and top but
not at the front.b
Of course there's no daylight at the front of the lugs. They pressing against the slide lugs in opposition as the moving bullet exerts a forward drag on the barrel while the slide is hauling it backward against that drag. That's how it works.

And the upper barrel lugs never bear against the tops of the lug recesses in the slide.

Quote:
the barrel is fully tilted downward and no part of it seems to
protrude from the slide.c)t
No, the barrel isn't tilted. The link hasn't swung far enough to do that...and you won't see any of the barrel protruding from the front of the slide until the barrel stops on the vertical impact surface...at nominally 1/4-inch of rearward travel. Until that happens, barrel and slide are moving rearward together.

Much to learn you have, young grasshopper. Teach you I will...but first you must accept that many of your beliefs are mistaken.
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Old January 18, 2013, 07:59 AM   #66
polyphemus
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OK Master Po Tuner
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Old January 18, 2013, 08:26 AM   #67
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Snark

Quote:
OK Master Po Tuner
Whoops! Sorry, lad. I don't do snark. I'm willing to explain this thing, but if you're gonna take that attitude, I'm all done.

Do carry on.
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Old January 18, 2013, 11:57 AM   #68
polyphemus
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No snide remark intended,simply following the line plot.
That barrel sure looks tilted downward toward the front,the amount of daylight
between barrel and frame seems to decrease as you go back,also of interest is
how little contact there is between follower and round it seems to have almost
no effect on how the cartridges line up which leads me to believe that the guide
lips are the main factor in the proper magazine function.
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Old January 18, 2013, 08:50 PM   #69
James K
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In the 1911 when the gun is at rest, the barrel is pointed down within the slide. But the sights are almost parallel with the top of the slide. As the bullet begins to move forward, the barrel begins to move back and down so by the time the bullet exits, the back of the barrel has dropped enough that the barrel is pointing (hopefully) to the same place as the sights.

Since barrel exit time depends on bullet velocity, the gun will be sighted for only one load (for the GI 1911, that is for the GI load) and any other load will shoot higher or lower. That is the advantage of adjustable sights if one wishes to fire any gun with more than one load.

Jim
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Old January 19, 2013, 04:56 AM   #70
1911Tuner
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Snark?

Quote:
No snide remark intended,simply following the line plot.
Okay. Maybe I was a bit hasty. I've been conditioned for it.

Let's proceed.

First, a quick primer on recoil.

Newton 3 states that for every action, there must be an equal and opposite reaction. This is Newton's Law...not Newton's Theory. Push on an object and you immediately get pushed away from that object by the force vector that exists between you. If that force is sufficient to set both objects in motion, then both will move at the same instant. They don't have a choice.

Recoil is nothing more than the reaction side of an action/reaction event. A result of force forward/force backward. An action/reaction system requires three things. Two interacting objects and a compelling force between them.
Remove any one of those components, and you can't have an action/reaction event. Once the bullet has left, the action side of the system is gone, and the compelling force with it. If there is no action, there can be no reaction. If there is no force, there can be no acceleration, and hence no movement.

i.e. If the slide hasn't moved until after the bullet exits, the slide won't move.
Kuhnhausen's "Balanced Thrust/Force Vector" description was well written, nicely illustrated, and interesting...and utterly wrong.

Here is the description of the firing/recoil cycle. To simplify it, we'll assume a condition of zero headspace and proper barrel linkdown timing.

Bang! The bullet and slide start to move at the same instant. Due to the slide/barrel assembly's greater mass, the bullet is accelerating some 33 times faster.

The barrel is under a forward drag from the bullet's frictional contact. The rearward moving slide grabs it by the lugs and hauls it backward with it...against the resistance of that forward drag. Newton 3 again. Whatever resistance is imposed by friction in one direction, is imposed in the other direction in equal measure. Whatever force resists the barrel's rearward motion, resists the slide's rearward motion.

The bullet exits at nominally 1/10th inch of slide/barrel movement. At the instant that the bullet base clears the muzzle the link just starts to tug on the barrel. The barrel has not dropped yet. The lugs are still fully engaged vertically.

At .200 inch of slide travel, the upper barrel lugs are just clear of the slide's lugs, but the barrel is still moving rearward on its own momentum. The link is still pulling on it.

At .250 inch of travel, the barrel is linked down as far as the link will bring it, and its rearward momentum is stopped by the vertical impact surface. (VIS) If all is within spec, there is .003 inch of clearance between the bottom of the barrel and the top of the frame bed...and the barrel free-falls to the bed by gravity. If all is within spec, and the linkdown timing is right, there is .012-.015 inch of clearance between the top of the barrel and the underside of the slide's first lug.

NOW...you'll start to see the barrel protrude from the front of the slide.

The slide continues rearward via the momentum that it conserved during the acceleration phase...while the bullet was still present.

You can see the point of full linkdown/barrel impact on the VIS by simply pushing the muzzle straight back until it stops. (Cock the hammer first.)

Cycling it manually on the bench, you'll see a little barrel drop almost immediately because the lower lug is angled slightly, and gravity will pull it down as soon as the lug moves off the slidestop pin...but that won't happen during firing because the upper lugs are horizontally engaged in opposition under force. You can see how that works by using a tight-fitting plug in the barrel...such as an oversized cleaning patch on a rod...and pulling forward on the barrel while you have someone move the slide slowly. The barrel won't start to drop until the link has swung far enough...or about .100 inch...and will continue to drop until it contacts the VIS.

In the photo, the slide appears to have moved about .075 inch...so the barrel couldn't have tilted at the rear.
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Old January 19, 2013, 05:13 AM   #71
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Lips

Quote:
also of interest is
how little contact there is between follower and round it seems to have almost
no effect on how the cartridges line up which leads me to believe that the guide
lips are the main factor in the proper magazine function.
Correct...sorta.

Before the slide has moved rearward past the magazine, there is no contact between the top round and the feed lips. The center rail is pressing down on the top round.

When the slide uncovers the magwell, the top round moves up into position...above the bottom line of that center rail. If it didn't, the slide would ride over the top round and never pick it up. That's why you feel spring resistance when locking in a magazine with the slide forward.

We'll address that a little later, with photos that illustrate the two basic different feed lip designs and how they affect the angle of entry. Might be better on a separate thread since this one has kinda gone wide of the mark.
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Old January 19, 2013, 08:05 AM   #72
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A tour de force (that ok?)a lot to digest,thank you again for taking the time.
Actual barrel slide separation takes place fractions of a second after rearward
movement of both,this is the critical point.A more thorough reading of the post
is needed,probably more than one.As to the round geometry in the magazine
this one requires spatial thinking to understand sort of like the disconnector
function.I digress,much obliged.
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Old January 19, 2013, 08:57 AM   #73
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re:

Quote:
Actual barrel slide separation takes place fractions of a second after rearward
movement of both,this is the critical point.
Yes. Separation occurs after the lugs have vertically disengaged. A timed event that occurs at its assigned place in the cycle...regardless of the speed of the cycle. Firing normally or in slow-motion by hand...the barrel begins linkdown at .100 inch, and it's completed at .250 inch of travel.

While the lugs are still vertically engaged, the slide and barrel can't separate.

Which incidentally, is why the pistol can't fire far enough out of battery to kaboom. At .100 inch out, the hammer can't reach the firing pin...so even if it could fire that far out...the lugs are still engaged and the breech can't open.
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Old January 19, 2013, 10:31 AM   #74
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Tuner - I love your posts because they are clear and concise in your explanations - and I alway learn a lot.

My only question about FLGR is, why do some gunsmiths use them for their 1911's? I have a custom 1911 built by Bob Marvel, whom I would assume knows as much about 1911's as anyone, and Bob uses a FLGR. At the cost of his builds, it makes no sense that it was used only to "increase the cost," as is often touted as the reason behind using them. If you look at the cost of the FLGR versus GI guide rod - the cost difference is inconsequential in the overall price of the gun.

When Bob built the pistol, I told him to do whatever he wanted, and to build it the way he thought best. When I received it from Bob, I have to say, I was surprised that it came with a FLGR - but, there it was.

The gun is exceptionally accurate. The two test targets are from 50 yards and the 10 shot groups are <1.4 inches - but, I would assume that could be done with or without the use of a FLGR.

Do you have any thoughts on why the FLGR was used? Personal build style? Aesthetics? Performance reason? Or...?
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Old January 19, 2013, 11:58 AM   #75
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re:

Quote:
My only question about FLGR is, why do some gunsmiths use them for their 1911's?
Don't know the answer to that one. Aesthetics? Because it's expected?

The FLGR is inert. It doesn't move, and it doesn't do anything that the standard length guide rod doesn't do just as well. It neither enhances nor degrades the accuracy or reliability of a 1911 pistol, other than making field-stripping a little more trouble.

So, it again raises the question:

"What is it for?"

The only answer that I can come up with is:

"To sell."
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