I have a Colt Stainless Gunsite pistol the barrel bushing fit is nice. Barrel to bushing and bushing to slide. What I noticed is the barrel lug has a small amount of play when it comes into contact with the notch it engages in the slide.
This is allowing the bushing to slide forward and back about 1/16" or less.
Will this damage the bushing, barrel, or slide? Accuracy is great so I'm on the fence as to swap the bushing with a new one.
The average Government Model M1911A1's bushing will have 0.006" of fore-aft play in the slide. If you want to determine why yours seems to have so much play, Ordnance blueprints for the slide and bushing are available in our Tech Issues section, 14th link down.
1/16" is .0625. You say "or less" -- how much less? Did you measure it, or is your 1/16" a guesstimate based on the M3A4, Mod2 eyeball method?
As you can perhaps tell from niemi24s's response above, we stand ready to assist and advise, but we have difficulty basing solid advice on "it looks like it's about ___."
Shouldn't the recoil spring take up all that slack in battery, anyway?
Typically, yes. Mass produced 1911's will usually have pretty generous tolerances and that includes the fit of the bushing. Such tolerances don't help accuracy, but it makes it easier to manufacture and assemble pistols and it's easier to field strip them. 1/16" is about 0.062" of movement and that is a whole lot, about 10 times more than what you will find in most 1911's.
While the average gap is 0.006" as previously mentioned, it can be as much as 0.010" or a little as 0.002" on a Government Model.
I can't get a handle on this. If the vertical & horizontal play is within specs on the barrel,what difference does the end-play on the bushing matter as regards accuracy? Assuming the bushing is tight on the slide?
Quote:
. . .what difference does the end-play on the bushing matter as regards
accuracy?
No difference.
I'm not sure where our resident blueprint expert came up with these numbers. The blueprints I looked at show the slot in the slide at .128" +.005, and the lug on the bushing at .091" - .006. Using those dimensions, the clearance between the two would range from .037" to .048". However, in order for you to see that full amount as fore-aft slop, it would mean that the slot has to be cut sufficiently forward that the bushing can be pushed all the way to the rear of the slot before the bushing flange contacts the slide and arrests further movement.
I'll ask again: Is that 1/16" an accurately measured dimension, or is it an eyeballed estimate?
In addition to the widths of the slide slot and bushing tab, their distances from the nose of the slide and the aft surface of the bushing flange must also be taken into consideration.
The play (and gap) are solely determined by those later distances as the aft surface of the tab can never touch the aft surface of the slot if the parts are within spec.