A question for the experts re loosening slide to frame fit.


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harmonic
August 5, 2008, 10:34 AM
When I first started shooting (1978) I bought a Colt Mk4/Series 70 govt model 45 ACP and sent it to Jim Clark for a target package. Along with everything else he did he tightened the slide to frame fit.

It's too tight. I figured I would "shoot it loose" but since 1978, according to my shooting log, I've only fired 1,691 rounds through it.

I want to start shooting it again, but it's still too tight. (Age+arthritis+weakening hands)

Somebody, somewhere, recommended the following approach: 1) JB Bore lapping compound; 2) Mix 2 parts oil to 1 part JB lapping compound; 3) Hand cycle 500 times; 4) Blow out compound with WD 40.

Suggestions? Is the above an acceptable alternative to sending the gun back to Clark for them to "loosen?"

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Rustynuts
August 5, 2008, 07:20 PM
Where is it too tight? Slide to frame, or slide to barrel? Either way I would just do a semi-agressive "fluff & buff". Get some fairly fine wet/dry sandpaper (autoparts store should do) and go to town on all the mating surfaces.

At first I would go no lower than 800 grit. Use whatever liquid to lubricate things, even water if you dry it up nice later. Some solvents though tend to eat through the sandpaper as well. Once you get it pretty close, I would then step up the grit progressively thru 1000, 1500, and maybe 2000. The finer grits will polish it off nice and smooth things further without taking off too much metal.. With polishing compound, you might be there forever!

You can use the sandpaper wrapped around a stick to get in the grooves of the slide/frame. Just try not to round off the edges too much (or at all!).

tipoc
August 5, 2008, 07:42 PM
harmonic,

Rustynuts, asked a couple of questions that I think are important. One is exactly where and how is the gun too tight?

When the gun is disassembled (barrel, spring, guide rod out) does the slide ride freely on the frame? Or is it tight and hard to move?

When assembled does the gun seem too tight in lock up? Barrel to bushing fit?

That you only have 1671 rounds through the gun suggests that you used it rarely or only for bullseye shooting. It'd be a shame to loosen up a good range gun too much. Better to know exactly what's making it too tight for you.

Once you do know exactly what is too tight the lapping compound approach may work. As it removes less metal I'd try that first. If it doesn't work rather than sand paper on a stick I'd try a set of stones. Brownells sells for a few bucks, sets of stones for the 1911 that will fit inside the grooves of the rails and when used carefully won't round off the edges of the rails.

You can also call Clarks and ask for their advice. They are very good on this sort of thing.

One other thing to try...A friend who has an injured weak hand racks his slide by holding the slide firmly in his weak hand close to his body. He then pushes the frame forward with the strong hand while holding the slide steady. In essence he pushes the frame into the slide rather than racking the slide backward. Try this and see if it works for you.

tipoc

1911Tuner
August 5, 2008, 07:49 PM
Start with a little straight J&B Bore compound. Shoot the gun 50 rounds and reapply. Shoot 50 more.

Field-strip it...dry wipe the rails... and use a 50/50 mix of J&B and CLP Breakfree or FP-10 oil. Don't be shy. Slop it in and coat the upper and lower barrel lugs. Go shoot it normally.

Field-strip and clean thoroughly and oil well with the same stuff you used to make the slurry. If that doesn't free it up a bit, you may need to do a little surgery.

32winspl
August 5, 2008, 08:13 PM
Hey harmonic. Is the gun just not working? Is it failing to feed? Can you operate the slide? Back then, "tightening the action" of a factory gun often involved peening the slide and rails. It not only worked well, but was repeatable.

Please be more specific. What problem are you having? I have to say that whatever problem you're having is likely not due to whatever work you had a 1911 Magician do to your pistol. Please be more specific.

1911Tuner
August 5, 2008, 08:40 PM
Please be more specific.

Very often, the issue is that the gun is hard to hand-cycle from in battery due to the barrel being such a tight fit. It's literally wedged into the slide on two planes between the lower lug/slidestop pin and the breechface/barrel hood area.

People with arthritic hands may have a tough time operating it. Loosening it up just a tick can make all the difference in the world to such folks.
I suspect that this is where his problem is...and the cure is usually simple. It won't degrade the accuracy one whit, and is no more than accelerating the "break-in" that was suggested to him by the smith.

Once in a while, it's not quite enough and requires a bit more...also simple.

You'll notice that I tweaked your post just a little. It seemed to be a bit...confrontational...for a response to someone who asked a legitimate question. Just keep in mind that one day, your hands will be old and cranky, too. ;)

harmonic...If you're within driving distance, I'll be happy to take care of that hitch for ya. No charge.

harmonic
August 5, 2008, 10:08 PM
Thanx tuner. You hit the nail on the head.

But let me ask you a question.

Let's say I'm loading 200 SWC copper plated (Barnes) bullets ahead of 6.2 grains Unique. What's the lightest recoil spring I can use without creating a situation where the slide is excessively battering the frame?

And let's say I install that spring. Can I safely fire hardball ammo without battering the frame?

thanx

1911Tuner
August 5, 2008, 10:30 PM
A 16-pound spring will do just fine, harmonic...and it'll also do for hardball. My go-to load is also a 200-grain SWC and 6 grains of Unique...so we're not too far apart on that. Good load, too by the way.

If you use an EGW square-bottomed firing pin stop with a light bevel on the corner...and a 23-pound mainspring...you can get by with a 14-pound recoil spring.

I see you've figured out that the heavier the recoil spring, the sharper the recoil.

My hands and wrists are also starting to protest a little...so I understand.

The offer stands. If you can bring it, I'll tune it. It's what I do... ;)

harmonic
August 6, 2008, 01:54 AM
tuner, part of the problem is the slide serrations. The slide serrations on my Combat Commander Series 80 are very crisp and are easy to hold.

The slide serrations on the gun in question has been satin nickled and the serrations almost feel smooth/slippery. Can you maybe recommend a metalsmith to recut the serrations, plus add some on the front of the slide?

thanx

1911Tuner
August 6, 2008, 08:03 AM
Nickel presents a little problem in that...once it's breached...it tends to flake and peel. Cocking the hammer before working the slide will help.

For that "sticky" initial travel from in battery, you can place the recoil spring plug against a tabletop and use your arm strength to break it loose.

If the barrel has also been plated, the J&B/Oil slurry may not help much.

If all else fails, you can send the pistol to the younger Clark to see if he can resolve the issues. He's carrying on the tradition, and I'm sure that he'd probably like a chance to see a pistol that his daddy built so many years ago.

harmonic
August 6, 2008, 10:30 AM
Tuner, you said,

If you use an EGW square-bottomed firing pin stop with a light bevel on the corner...and a 23-pound mainspring...you can get by with a 14-pound recoil spring.


I had a stainless steel flat mainspring housing installed on the gun a couple of years ago. I'm going to assume the spring is factory spec at 23 pounds.

Would that be a correct assumption?

If so, you're saying I can install a 14 pound recoil spring and not have the slide batter the frame during shooting?

What about the hammer spring? How light can I go on that without having too light hammer strikes?

And you mention the firing pin stop. Does anyone make a drop-in firing pin stop that has the configuration you describe?

1911Tuner
August 6, 2008, 10:58 AM
I'm going to assume the spring is factory spec at 23 pounds.


Correct. The standard mainspring is rated at 23 pounds. If Clark did a match trigger job on the gun, there's at least a chance that the spring is lighter than that.

If so, you're saying I can install a 14 pound recoil spring and not have the slide batter the frame during shooting?

You can probably go even lighter with the recoil spring if you use the square EGW stop. Although it's become accepted that the standard recoil spring is 16 pounds...that's actually a bit oversprung from an original design standpoint.

It was never really specified in pounds, but rather wire diameter and number of active coils.

"32 and 3/4 turns of .043 music wire."

Compared to a Wolff 14-pound/32 coil spring, that works out to be about 14.5 pounds.

Later, the specs were revamped to 30 turns of .044 diameter wire...and it's back to somewhere around 14 pounds when compared to a Wolff 16-pound spring.

So...16 pounds is just a bit much. It's not frame battering that you need to be concerned with so much as the slide anyway, and neoprene shock buffs can put your mind at ease if you want to go that route. Be aware that some pistols run just fine with the buffs in place, but a few don't. If yours does, just change it out whenever it starts to get beat up, and change the recoil spring every couple thousand rounds.

What about the hammer spring? How light can I go on that without having too light hammer strikes?

The hammer spring IS the mainspring, and it has a strong effect on delaying and slowing the slide. Moreso even than the recoil spring.

Ned Christiansen ran an experiment several years ago with a 10mm Delta Elite in which he bumped up to a 25-pound mainspring and a square-bottomed firing pin stop. He was able to drop the recoil spring all the way down to 18 pounds from the standard 22 pounder, with no loss of slide to frame buffering...and the gun was much more user-friendly with the lighter recoil spring.

I don't know of anybody who makes a drop-in firing pin stop, but if you contact George Smith at Evolution Gun Works and provide him with the dimensions...he'll probably cut one that will drop in for a nominal extra charge...and he'll cut the radius on the bottom that you want. I'd ask for 1/16th inch. If you can't get the dimensions, you can send him your old one to copy. George is very easy to work with and means to please. He's also a genuinely nice guy. If you explain your situation to him, I'm confident that he'll do what he can to help.

harmonic
August 6, 2008, 11:07 AM
Thanx tuner.

You know, lately I've become a little disenchanted with the overall mentality and experience of some of the posters on some of the threads re political and ideological topics here, but it's pretty much your contribution and the contribution of the experts on the tech portions of THR that keeps me coming back.

You and the other experts dispensing sage advice on the specified threads are a class act.

thanx for the help.

1911Tuner
August 6, 2008, 11:41 AM
Thanks, harmonic. I do what I can. ;)

Mad Magyar
August 6, 2008, 12:07 PM
You know, lately I've become a little disenchanted with the overall mentality and experience of the posters here,
And the rest of us are chopped liver.....

Jim Watson
August 6, 2008, 12:20 PM
The slide serrations on the gun in question has been satin nickled and the serrations almost feel smooth/slippery.

"Sharpening" the serrations and adding front serrations would cut through the plating and either look strange or require replating with care not to buff off the corners of the serration. It would be an expensive proposition.

Some strategically located patches of skateboard tape, stair tread tape, or aircraft wing walk would add a lot of grip at low cost. It would still look odd on the plated gun, however.

Walkalong
August 6, 2008, 12:54 PM
And the rest of us are chopped liver.....I really don't believe he meant it like that.

Some posters, some of the time, can be quite "snippy". Old Timers, and I am getting to be one, often times have little patience in that area. :)

Excellent advise Tuner. I read it all with great interest.

atblis
August 6, 2008, 12:57 PM
Send it to me with along with 5k rounds of ammo or so and I'll loosen it up for you. No charge.

harmonic
August 6, 2008, 01:49 PM
I really don't believe he meant it like that.

Some posters, some of the time, can be quite "snippy". Old Timers, and I am getting to be one, often times have little patience in that area.

+1. I actually didn't even mean the tech sections. Anything to do with technical, reloading, gunsmithing information 999 times out of 1000 will bring out measured responses from truly eloquent and experienced posters.

But on other sections of THR, viz. the political, social, "tacticool" sections, I get the distinct impression it's populated by mostly prepubescent males who glean their knowledge from cartoons and video games. Because their contribution sharply tapers off when school starts.

Present company excluded.

Rinspeed
August 6, 2008, 03:36 PM
Thanks, harmonic. I do what I can.



Great advice as always Tuner.

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