I am trying to tighten the slide on my Kimber, but the slide just keeps returning to the same width. Do I need to squeeze more, or does stainless have too much memory? Is there any formula or known measurements that say for every .005 in. of movement should give you .001 in.?
I don't have them here with me, but Kuhnhaeusen, in his books on the M1911 gives the formula for tightening the slide to frame fit. You need to squeeze the slide more than the desired finish width, following Kuhnhaeusen's formula, to allow for spring back of the steel. Either stainless or steel or plain steel will spring back. Whether or not they will spring back the same amount I don't know. The best thing to do is to get a copy of Kuhnhausen's books and follow his instructions, if you don't already have them.
Thanks for the info. I have squeezed it .020+ and it still springs back. I will look for his book.
KRM, man you are in the realm of no return when you start to pinch your slide. If you are lucky you will manage it without having to have it spread back open without cracking at the safety slot. Safer approach to this problem on your Kimber. If it is just at the beginning of rattle, it is pretty tight for stainless, which is prone to gall. Railing bars and a 2 ounce ball peen with a rounded face. Take the frame rails out into the slide instead of pinching, if it is not a rattle trap. If you are pinching with out gauges in a vice, remember to use a smooth jaw vise with no grit in the lever and only pinch behind of the ejection port.
Thanks for the input Sam. I heard that modern stainless steel alloy that is used for making guns is not prone to galling, especially if you use any lube. I don't think galling will be a problem. The main reason I want to squeeze the slide is because it is quite a bit wider at the breech face and middle of the ejection port than it is at the rear and front. The rear of the slide is pretty tight. This gun shot 10+" at 25 yards until a match bushing was installed. Now it still shoots 6". I use it for USPSA and would like for it to be a little more accurate. Any other suggestions would be appreciated.
All the points that Sam mentioned are covered in Kuhnhausen's books on the M1911 along with complete instructions, and all of them are valid concerns. Tightening the slide to frame fit is only going to net you perhaps a 15% increase in accuracy. You might be better off measuring the slide to frame fit, both horizontal and vertical, and if it is allready within the low side of within spec's for a factory M1911, have a match grade barrel fitted instead. The fitted match grade barrel should net you a greater increase in accuracy than tightening the slide to frame fit. You can allways tighten the slide to frame fit later if you like.
+1 for what Toolman just said. You need to measure the amount of play between the slide and frame. Then measure the amount of play at the muzzle and at the aft end of the barrel when the gun is in battery. Comparing these two plays will give you an idea of where the most accuracy can be gained. In a well-fitted gun, when the slide goes into battery, it wedges the barrel between the slide and frame and everything is in the same position when the gun's fired. If the barrel is not wedged between the frame & slide, the barrel's location relative to the line of sight is uncertain and accuracy will suffer.
Believe me it will gall up. I am not into this thing of saying I have vast amounts of experience, but I do in this area. Stainless on stainless is always harder to get tight without it galling up on you. Smith & Wesson has a balance in hardness between slide and frame to help with this problem, but then they also do not overtighten. I have pinched, peened and fit hundreds of stainless guns and always set them a little loose, but tight with oil on the rails. I just prefer the railing bar method over pinching on everything if It"s not too loose. Stainless is full of chromium which makes it softer than carbon steel mixtures. Carbon on stainless can render a tight pistol. I'm only trying to save you the headaches I have already had, besides pinching a stainless slide is usually a waste of time, usually spring back out after several hundred rounds.Now for the accuracy concern, look somewhere else for a problem (leaded up barrel). Slide to frame fit is only about 15% at the most. Most Kimbers I have shot are one holers at 15 yards off the bench. Not to sound to critical, but I bet its something else.