Slide to Frame Fit [Archive] - Glock Talk

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ricklee4570
07-19-2011, 15:44
Should there be any slide to frame play on a new 1911?

Im considering a couple and in comparing the two I noticed that one has a tiny amount of side to side play. If you grasp the frame tightly with one hand and grasp the slide with the other and move it side to side, you can see and feel some lateral movement. The rear of the slide is just enough to be perceptable but the front is more noticeable.

Also, when in battery if I push down on the barrel it has a very small amount of downward movement.

With todays modern 1911's that run in the $900.00 to $1100.00 range I wasn't sure if this is normal.

Thanks!

drc767
07-19-2011, 15:52
It is quite normal, to be honest. Slide to frame fit does not have any effect on accuracy in a 1911. The slide to frame clearances will vary quite a bit from one pistol to the next from the same manufacturer on production 1911's. Choose the one that feels best in your hand and go with it.

knedrgr
07-19-2011, 16:43
+1 on what Dave said. More concerning is the springing of the barrel 's hood area. You don't want that, since it will affect accuracy.

custom2
07-19-2011, 19:52
It is quite normal, to be honest. Slide to frame fit does not have any effect on accuracy in a 1911. The slide to frame clearances will vary quite a bit from one pistol to the next from the same manufacturer on production 1911's. Choose the one that feels best in your hand and go with it.


Not exactly true. Slide to frame fit does have an effect on accuracy. The thing is, most shooters are not proficient enough to have that effect detract from their accuracy. While it is true that the vast majority of a 1911's accuracy comes from the quality and fit of the barrel and bushing, it would be wrong to say that slide to frame fit has NOTHING to do with accuracy. Many pistolsmiths and pro shooters search for that perfect slide to frame fit for a reason.

Take a loose pistol, peen and hand lap the rails and shoot it. Tell me if you notice a difference. Most won't. The guy who is upset when he usually shoots 1 inch groups at 25 yards only shoots 1.25 inch groups will.

drc767
07-19-2011, 20:05
Not exactly true. Slide to frame fit does have an effect on accuracy. The thing is, most shooters are not proficient enough to have that effect detract from their accuracy. While it is true that the vast majority of a 1911's accuracy comes from the quality and fit of the barrel and bushing, it would be wrong to say that slide to frame fit has NOTHING to do with accuracy. Many pistolsmiths and pro shooters search for that perfect slide to frame fit for a reason.

Take a loose pistol, peen and hand lap the rails and shoot it. Tell me if you notice a difference. Most won't. The guy who is upset when he usually shoots 1 inch groups at 25 yards only shoots 1.25 inch groups will.

Just for sake of argument, let's suppose slide to frame accounts for 10% of the accuracy of the pistol. A pistol that shoots 1" groups is now shooting .90" groups with a tightened up frame/slide.....I am not sure anyone, I don't care how good you are, will notice .10 difference in accuracy. Maybe I shouldn't have said there slide to frame fit has "nothing" to do with accuracy.....I should have said it is very negligible, at best. If the barrel locks up into the slide tightly each time it cycles and the sights are tight on the slide then slide to frame fit is really not very important to accuracy.

custom2
07-19-2011, 20:40
DRC, I totally agree with what you just said. What I should have said was it wouldn't matter to most shooters, that extra .10 inch. Not that they wouldn't notice. Thanks for pointing that out.

I would say the top 2% of shooters would pay huge money to get that exta 10 percent. But they are at a level where they shoot as good as their pistol. Most of us would say their pistol is capable of more accuracy than we can provide.

glock2740
07-19-2011, 20:57
I agree with Dave. I'm not a stickler for slide to frame fit. A well fitted barrel and bushing make alot more difference than slide/frame fitting.

bac1023
07-20-2011, 02:26
Should there be any slide to frame play on a new 1911?

Im considering a couple and in comparing the two I noticed that one has a tiny amount of side to side play. If you grasp the frame tightly with one hand and grasp the slide with the other and move it side to side, you can see and feel some lateral movement. The rear of the slide is just enough to be perceptable but the front is more noticeable.

Also, when in battery if I push down on the barrel it has a very small amount of downward movement.

With todays modern 1911's that run in the $900.00 to $1100.00 range I wasn't sure if this is normal.

Thanks!

Completely normal. Some have movement, others have little to none. You normally won't see much at all when dealing with the higher end models.

CMG
07-20-2011, 06:18
A tight slide-to-frame fit isn't vital to accuracy, but it often indicates a level of attention to the pistol's assembly that lends confidence it was done correctly and with care.

My Kobra, TRP and Trophy Match had no discernible movement in the slide to frame fit.
Likewise, the barrel fit was solid at both hood and bushing.

bac1023
07-20-2011, 11:59
A tight slide-to-frame fit isn't vital to accuracy, but it often indicates a level of attention to the pistol's assembly that lends confidence it was done correctly and with care.

My Kobra, TRP and Trophy Match had no discernible movement in the slide to frame fit.
Likewise, the barrel fit was solid at both hood and bushing.

Very true

Barrel lockup is much more vital to good accuracy than silde to frame fit.

HAIL CAESAR
07-20-2011, 14:11
"Slide to frame fit"

Don't worry about it.

bac1023
07-20-2011, 14:17
"Slide to frame fit"

Don't worry about it.

I do think people worry far too much about it, quite honestly.

HAIL CAESAR
07-20-2011, 14:51
I do think people worry far too much about it, quite honestly.

I think so also. It is much over thought and worried about, with no real reason.

harrygunner
07-20-2011, 14:58
I've read that one should not be able to push the barrel downward when it's locked to the slide. Indicates improper fit of the lower barrel lugs. My two custom 1911's have no movement at all when I push on the barrel hood.

About slide fit, fast action video shows the bullet leaves the barrel very soon after the slide starts moving. Rough estimate using conservation of momentum and ignoring small effects leads to the slide moving a little over 0.1 inch before the bullet leaves the barrel. This implies slide-to-frame has limited effect on the point of impact.

It could be argued that slide-to-frame fit can only subtract, never add to precision. And would have no negative effect only if the rails were cut and aligned perfectly.

First, I'm imagining a loose fit for a slide, meaning the frame won't be imparting much force on the slide as the slide moves. With a proper breech face angle and properly fit upper and lower barrel lugs, the impulse vector coming from the cartridge case would lie on the axis of the barrel. This would cause the slide to move perfectly backward, imparting no transverse forces on the barrel.

Second, imagine a tight, perfect fit plus perfectly cut and aligned rails. That would have the same effect as above, but no better precision

Finally, a tight fit on a less than perfect rails would cause the frame to push the slide/barrel in some direction perpendicular to the barrel's axis, reducing precision.

Any holes in that thought experiment?

HAIL CAESAR
07-20-2011, 15:23
Any holes in that thought experiment?

The only thought I have after reading your post is as follows;

Whatever money you spent for your education, was money well spent.:wavey:

lsbbigdog
07-20-2011, 15:34
I've read that one should not be able to push the barrel downward when it's locked to the slide. Indicates improper fit of the lower barrel lugs. My two custom 1911's have no movement at all when I push on the barrel hood.

About slide fit, fast action video shows the bullet leaves the barrel very soon after the slide starts moving. Rough estimate using conservation of momentum and ignoring small effects leads to the slide moving a little over 0.1 inch before the bullet leaves the barrel. This implies slide-to-frame has limited effect on the point of impact.

It could be argued that slide-to-frame fit can only subtract, never add to precision. And would have no negative effect only if the rails were cut and aligned perfectly.

First, I'm imagining a loose fit for a slide, meaning the frame won't be imparting much force on the slide as the slide moves. With a proper breech face angle and properly fit upper and lower barrel lugs, the impulse vector coming from the cartridge case would lie on the axis of the barrel. This would cause the slide to move perfectly backward, imparting no transverse forces on the barrel.

Second, imagine a tight, perfect fit plus perfectly cut and aligned rails. That would have the same effect as above, but no better precision

Finally, a tight fit on a less than perfect rails would cause the frame to push the slide/barrel in some direction perpendicular to the barrel's axis, reducing precision.

Any holes in that thought experiment?

I had to use a dictionary to figure out some of those words :tongueout:

harrygunner
07-20-2011, 16:36
Well, simply stated, not really important. I had my gunsmiths eliminate any slide rattle.

In that 0.1 inch of movement, the barrel is still locked to the slide, so I could see the need for a tight barrel bushing. Had those custom fit to the new barrels in each gun. But, I couldn't imagine a rail cut so bad that the effect could not be rectified by adjusting the sights a little.

harrygunner
07-21-2011, 15:54
This thread caused me to notice why the mechanics of a 1911 can handle so many different kinds of ammo. A simple design, yet subtly sophisticated.

The conservation of momentum thing is baby physics, but implies:

1) The slide displacement is independent of the speed of the bullet. So the slide will move the same fraction of an inch for a 200gr .45 ACP moving at 900 ft/s as it would for a 200gr 10mm moving at 1200 ft/s.

2) The lower the mass of a bullet, the lower the slide displacement. If a 230gr bullet causes the slide to move 0.12" by time it leaves the barrel, a 185gr bullet will cause the slide to move 0.097". A 255gr bullet gives 0.13".

I'm not a gunsmith. What is the distance the slide moves back where the barrel link starts to pull the barrel down? I imagine even the 255gr bullet keeps the travel within the safe zone.


(These fractions of an inch were written with more digits to the right of the decimal point than warranted. Just wanted to show how they change. Numbers are based on a slide+barrel weighing about a pound and a quarter and the bullet having to travel about 4" in a 5" 1911 barrel. They are high since the recoil spring and bullet drag would cause the slide to displace less.)

GammaDriver
07-23-2011, 14:19
I don't know much about it, but my father who used quite a few .45's in the Army stated that the looser the 1911, the better he found it could handle dirt and grit out in the field... so would part of it depend on if you want a high-end range-queen or a trusty sidearm?

Personally, I would prefer a reliable and loose-fitting 1911 unless I was competition shooting in some class/category that did not involve getting down in the dirt. What we consider loose is what i understand as the way the original 1911's came out of the factory (I'm not saying they were specifically designed that way, but the looseness worked to our guys' advantage out in the field).

limbkiller
07-23-2011, 14:36
I don't know much about it, but my father who used quite a few .45's in the Army stated that the looser the 1911, the better he found it could handle dirt and grit out in the field... so would part of it depend on if you want a high-end range-queen or a trusty sidearm?

Personally, I would prefer a reliable and loose-fitting 1911 unless I was competition shooting in some class/category that did not involve getting down in the dirt. What we consider loose is what i understand as the way the original 1911's came out of the factory (I'm not saying they were specifically designed that way, but the looseness worked to our guys' advantage out in the field).

:thumbsup:

drc767
07-23-2011, 14:38
Believe it or not, there is such a thing as a "high end" trusty (ie. reliable) 1911, too.....Those who do not believe so, have obviously never owned a high end 1911 and just use such fiction to justify their "low end" 1911's.

GeorgiaRedfish
07-23-2011, 14:42
Believe it or not, there is such a thing as a "high end" trusty (ie. reliable) 1911, too.....Those who do not believe so, have obviously never owned a high end 1911 and just use such fiction to justify their "low end" 1911's.
LIES!













:tongueout:

bac1023
07-23-2011, 18:23
Believe it or not, there is such a thing as a "high end" trusty (ie. reliable) 1911, too.....Those who do not believe so, have obviously never owned a high end 1911 and just use such fiction to justify their "low end" 1911's.

Yeah, we see that here at times for sure. :dunno:

That said, GT is much better than some other forums in that regard.

drc767
07-23-2011, 18:59
Yeah, we see that here at times for sure. :dunno:

That said, GT is much better than some other forums in that regard.

Agreed, Brian.....I always get a kick out of the, "my 1911 is a rattling ****bucket, but it is more reliable than a hand fit, custom/semi-custom 1911" because they are fit too tight. I think the Les Baer Thunder Ranch (for starters) has pretty much taken care of that debate....Look at Clint Smith's TRS and tell me that thing has not seen more abuse than 99% of any 1911 anyone has ever seen......and that includes the battlefield.

glock2740
07-23-2011, 22:10
Agreed, Brian.....I always get a kick out of the, "my 1911 is a rattling ****bucket, but it is more reliable than a hand fit, custom/semi-custom 1911" because they are fit too tight. I think the Les Baer Thunder Ranch (for starters) has pretty much taken care of that debate....Look at Clint Smith's TRS and tell me that thing has not seen more abuse than 99% of any 1911 anyone has ever seen......and that includes the battlefield.

Something like this...:whistling:


http://i914.photobucket.com/albums/ac341/OU1911/Guns031.jpg

:cool:

skdmrklcy
07-24-2011, 09:55
My Colt is not as tight as my TRP was, but the barrel to bushing feels the same in both.

If the Colt sticks around... It will be sent out for some work, and it will be tightened up. I don't think it needs it, but if I am going for it, I am going to go all the way!

I think if it is not super tight it is easier to be reliable, while it is still possible to be reliable while being tight it just takes more work.

Cerebrus
07-24-2011, 10:05
Pulled this from here...http://findarticles.com/p/articles/mi_m0BTT/is_153_25/ai_75211979/
"Vickers said the slide fit really doesn't have that much to do with accuracy, but shooters have come away with the impression that slide-to-frame fit is important, mainly because it's something that can easily be checked by a nimrod. ""It's something the average guy can check, so he thinks it's important, but it's really not,"" Vickers stated."

From what I understand Vickers knows a thing or two about the 1911..:supergrin:

RH45
07-26-2011, 15:50
This thread caused me to notice why the mechanics of a 1911 can handle so many different kinds of ammo. A simple design, yet subtly sophisticated.

The conservation of momentum thing is baby physics, but implies:

1) The slide displacement is independent of the speed of the bullet. So the slide will move the same fraction of an inch for a 200gr .45 ACP moving at 900 ft/s as it would for a 200gr 10mm moving at 1200 ft/s.

2) The lower the mass of a bullet, the lower the slide displacement. If a 230gr bullet causes the slide to move 0.12" by time it leaves the barrel, a 185gr bullet will cause the slide to move 0.097". A 255gr bullet gives 0.13".

I'm not a gunsmith. What is the distance the slide moves back where the barrel link starts to pull the barrel down? I imagine even the 255gr bullet keeps the travel within the safe zone.


(These fractions of an inch were written with more digits to the right of the decimal point than warranted. Just wanted to show how they change. Numbers are based on a slide+barrel weighing about a pound and a quarter and the bullet having to travel about 4" in a 5" 1911 barrel. They are high since the recoil spring and bullet drag would cause the slide to displace less.)

Now, I understand why a couple of pistols I own, that aren't real tight, shoot tighter groups with lighter bullets!:wow:

harrygunner
07-26-2011, 18:51
I believe John Moses Browning understood classical physics very well. I concluded that based on his fix for soldiers complaining about how hard it was to pull back the slide.

Within the constraints of a production product, he realized that reshaping the firing pin stop would lengthen the moment arm for the force the slide places on the hammer.

Nice, clean, easy fix. Today a committee would decide the gun has to be redesigned.

RobertW44
11-18-2011, 20:32
I had a Kimber Warrior with some play in the slide, it was extremely accurate and never jammed. I bought my second Glock 34 today, traded my other one awhile back. This one is looser then the other one and is more accurate. I think there are too many variables to consider to be too concerned about a really tight fit.