Fit of Slide to Receiver

[FarAim]

From time to time I see people asking about the best slide/receiver fit. Perhaps the following will be of some help. The other day I went to the range to use up some assorted ammunition. I hand a Springfield Loaded, A Springfield WW2 model, and a 80 series LtWt. Commander. The Loaded has a slide/receiver fit that was about normal, just the tiniest bit of play. The WW2 is so tight and slick that I am thinking about building it up into a match gun. And the Commander rattles so much that I am tempted to look on the ground for spare parts after shooting it. I installed a Wilson bushing, and an EGW slide stop to attempt to tighten things up a bit.
When I got home I noticed that the WW2 averaged about an inch in width, but over 2 inches in height; new sights are on the way. The loaded averaged a little under 2 inches, but the Commander grouped better,(more rounded) and averaged 2 inches! All shooting was at 15 yards, unsupported.
No longer will I be concerned about the elusive slide/receiver fit on a combat arm.

[perry1963]

There's a post somewere here that say's the slide to frame fit is only a small percent of the guns accuracy, i've always belived that a good barrel and bushing fitted properly is the best thing you can do for accuracy, thats not to say a tight slide to frame fit isn't important but i think some people give it too much credit for accuracy.

[Jim Keenan]

I have posted on the subject and I don't think I said that slide to frame fit is a SMALL part of accuracy. I have said, and will repeat, that slide to frame fit is LESS IMPORTANT than slide to barrel fit. But one critical factor in accuracy is the way the barrel cams up on the slide stop pin, which in the frame. So the fit of the slide, which has the barrel, to the frame, which has the slide stop pin is important. It does not need to be extremely tight, and can even be loose as long as it does not affect the way the barrel rides on the pin and cams up to lock.

Jim

[Bob Hostetter]

The mechnical accuracy of a pistol is determined by the ability of the barrel to return to the same position when in battery, every time, in relationship to the slide. This is accomplished by fitting the frame and slide together, the barrel and frame together, and the barrel and slide together (I am including the bushing in the barrel fit, if so equiped).

The most important single item in the fitting is the lower lugs, followed closely by the bushing, barrel, and slide fit at the muzzle. Then would come frame to slide fit, and then upper lugs and hood.

As a side note, frame to slide fit is much more important on a pistol using frame mounted sights such as a red dot or scope. As long as the barrel returns to the same position relative to the slide each time, if the sights are mounted on the slide the barrel is also returning to the same position relative to the sights insuring mechnical accuracy. If the sights are mounted to the frame then the slide also has to return to the same position relative to the frame or there will be a misalginment between the sights and the barrel degrading the mechnical accuracy of the pistol.......

[OCG1911]

Bob you are on the money but practical accuracy for basic combat shooting is not effected by a tight frame to slide fit . Frame to slide fit is part of an equastion only when you trying for 99% weapon ruling out the pistol rather than shooter but for most just good basic skills, good trigger and sights 80 % of accuracy is met if want to split hairs then yes start with the process. I mean just because a new springfield is tighter than a colt does not mean a thing there other parts of the mystery possibly still not right. Factory guns are made to mass specs + or - and as long as they go bang and hit paper they have accompolished their goal . The process of accurizing can be done in phases or just as far as a new bushing or maybe match barrel but if you want the full meal deal it is all the above plus frame to slide fit this mechanical accuracy process brings the tolerances closer and the variables of pistol less ,now coupled with good clear sights and a trigger with crisp let off you now have gun that is repeatedley working in the same fashion round after round . Ocg 1911