Question about 1911's

[mark77418]

I have been reading a lot about 1911's and it seems like a lot of higher end guns have a lot of the parts hand fitted. My question is what is it about these guns that require extra gunsmithing work to make them fit together real we'll. Why is it that with modern day CNC machines do parts need to be filed and why does the frame and slide need to be matched for the gun to fit together well. My ar15 was put together from parts from different suppliers and the parts fit together very well and it runs flawlessly.

[tdyoung1958]

accuracy . . . it's the differences between thousands of a inch and ten thousands of a inch

[Paradiddle]

I have been reading a lot about 1911's and it seems like a lot of higher end guns have a lot of the parts hand fitted. My question is what is it about these guns that require extra gunsmithing work to make them fit together real we'll. Why is it that with modern day CNC machines do parts need to be filed and why does the frame and slide need to be matched for the gun to fit together well. My ar15 was put together from parts from different suppliers and the parts fit together very well and it runs flawlessly.

Doesn't just pertain to the 1911. That just happens to be one that has a lot of vendors. There are hand fitted CZ's and guys that hand fit Benelli's, etc. It's primarily either a competition or collector thing. 95% of shooters can't outshoot a stock Colt or Kimber (or Sig, Glock, etc.) - but it's a hobby so those of us with the money to spend can get a very nice Les Baer, or whatever and have a nice hand fitted gun.

Like the difference between a guy that restores cars, or hand builds his own engine versus a person that drives a Honda and is fine with it.

But don't think it's only about 1911s.

[jonzer77]

People trying to squeeze that last bit of accuracy out of an already accurate gun.

[21SF]

Plus the beautiful look and feeling of a tightly fitted gun.

[9mmepiphany]

It is because the gun was designed over 100 years ago when machining was expensive and hand-fitting was cheap.

It was designed from the outset to be handfitted.

It can be engineered with modern techniques in mind, but the basic cost of the resulting product is higher than many folks want to spend...so they start cutting corners in production. Most folks want to speed <$1k for a basic 1911, when they should be looking in the $1200-$1500 range

[sholling]

The design of the 1911 is such that it can be tuned until it works like a precision instrument but getting the most out of that requires an exact fit between components. You're right that Modern CNC mass production is a huge improvement over old fashioned mass produced parts but keep in mind that every mass component has tolerances - even CNCed parts. Just grabbing numbers out of thin ai the location of a hole in the frame may have a location tolerance of plus or minus .002" add similar tolerances for hammer and sear and they start adding adding up. Hand fitting makes up for flaws caused by stacked tolerances by assuring a perfect mating between components. Add in legal liability and a designs for a mass produced part has to error on the side of safety meaning extra "meat" has to be left to assure there are no NDs. That's extra material that a hand tuner removes a little at a time until the fit is perfect.

But on top of that hand work is used to polish out machining marks, reduce friction and allow tighter tolerances. For example S&W's Performance Center laps bushing to fit the barrel and the slide to fit the frame so that you have a zero slop yet near-friction-free fit. They go further and smooth each friction surface right down to the plungers for the safety and slide lock to remove all possibility of bind-up.

You can buy a perfectly serviceable and nicely configured 1911 (S&W or Springfield Armory "Loaded") for $1000 or you can get into the realm of a hand fitted 1911 perfection (Les Baer or S&W Performance Center) for around $1900 and way up from there.

[Jeepergeo]

Doesn't just pertain to the 1911....95% of shooters can't outshoot a stock Colt or Kimber (or Sig, Glock, etc.)...

I agree with Paradiddle. A great shooter can gain some with a precisely hand fit and tuned firearm. But for most shooters, me included, going beyond a mass market gun that maybe has some factory custom shop attention, like a Kimber Gold Match, will not make us noticeably better shooters. But such a gun is nice to own and to shoot.

It sort of like Snap On tools Vs Craftsman tools...both end wrenches will turn the nut about the same, with user satisfaction perhaps being the only difference.

[JeremyS]

The most modern manufacturers are choosing to use high-end CNC and other equipment (EDM machining, etc) to produce guns with tolerances as good as or even better than anything that can be done by hand, with better consistency.

Dan Wesson is a good example of a company making guns to extremely high tolerances without the need for hand fitting. They are not doing the kind of tolerances that require 1,000 rounds just to break in a gun because it's so tight that it may not run right, but are choosing to manufacture to tolerances that are approximately as tight as possible but still completely reliable.

On the extreme end of this is Cabot Guns, which can control tolerances to 40 millionths of an inch. Millionths.

http://cabotgun.com/cabot-guns-precision-1911-pistols/pistol-construction/frames-and-slides/

it's the differences between thousands of a inch and ten thousands of a inch

Yeah, see above. Sorry, but a dude with a file and some stones cannot achieve what modern machining can. Nobody on earth could hold a slide rail to 0.000040" (40 millionths) straightness along the entire thing. Not even anywhere almost remotely close. Cabot is doing this currently.

The reason some super high end custom-fitted guns MUST be broken in is because they are imperfect. The manufacturer leaves the gun itself and the rubbing of metal itself to actually do the final fitment, since he is not capable of being perfectly consistent. He comes close, errs on the side of metal contact, and lets friction wear away the rest. This is how you make the tightest possible gun by hand. If you could make the slide perfect and the slide rails perfect, and hold them to an insanely tight degree of straightness and size on both, you can get tolerances that are closer than you can do by hand and still have zero rubbing/binding issues that come from being a bit off. Yet, for some reason, we think that's the sign of a really well-fitted gun. It's just old-school thinking.


So, OP, the answer to your question is that hand fitting DOES NOT need to be done. Most manufacturers do it for two reasons. Well, one primary reason and then the second one is a function of that. One: the equipment needed to manufacture to a very high tolerance and require no hand finishing is very expensive. Two: most 1911 "manufacturers" only make a couple of parts themselves, most of the parts themselves, or even no parts themselves. They assemble parts from other manufacturers onto their guns and then put their name on it. Specs and tolerances will be different and, therefore, parts must be hand-fitted.

The original 1911 drawings are not as precise as modern machining is capable of, which means different manufacturers could keep to a 0.0001 tolerance on their own parts but still be a different size from another manufacturer keeping the same tolerance on their version of the part.

Given the right equipment and all parts coming from the same specifications so the relative sizing is all correct, you would not need any hand fitting and you can have results as good as or, even more likely, better than anything you could get hand-finished from the best gunsmith in the country.

[Cyc Wid It]

It is because the gun was designed over 100 years ago when machining was expensive and hand-fitting was cheap.

It was designed from the outset to be handfitted.

It can be engineered with modern techniques in mind, but the basic cost of the resulting product is higher than many folks want to spend...so they start cutting corners in production. Most folks want to speed <$1k for a basic 1911, when they should be looking in the $1200-$1500 range

Truth, per usual.

I will take a full house custom from any LTW smith over a Cabot gun.

[JeremyS]

I will take a full house custom from any LTW smith over a Cabot gun.

Sure. It's like a modern, tight-tolerances, computer-designed-and-manufactured, built-in-a-sterile room car (e.g. Nissan GT-R) vs. something mostly assembled and fitted by hand. Sure, the first choice might run laps around the second and beat it on paper in every possible way, but some people want the quirks and the "soul" that you simply do not get with something made entirely by machine. People can and will always continue to make that choice.

The OP's question, though ("Why is it that with modern day CNC machines do parts need to be filed and why does the frame and slide need to be matched for the gun to fit together well."), isn't answered by this. The answer is that parts absolutely, positively do not need to be finished by hand to achieve a good fit and that modern machining can, in fact, achieve a better fit than any by-hand method. Whether you still prefer the feel of a by-hand-fitted gun is a personal opinion.

[Cyc Wid It]

It's not just that, it's also the aesthetics and creativity behind various custom machined parts / checkering designs / bevel treatments / etc.

[dls]

Sure. It's like a modern, tight-tolerances, computer-designed-and-manufactured, built-in-a-sterile room car (e.g. Nissan GT-R) vs. something mostly assembled and fitted by hand. Sure, the first choice might run laps around the second and beat it on paper in every possible way,

...and sometimes the machine built just can touch the performance of a hand fitted high end engine,as in most super/race cars.

[mark77418]

Thanks for all the answers. I have glocks and I could never understand why anyone would pay 2 to 3 times the cost of a glock for a heavy chunk of metal. My cousin got a Kimber and I shot it and now I understand why people like them so much. I've been reading all I can about them trying to decide wich one to get.

[doc540]

precision machined does not necessarily equate to hand fitted

It can be the difference between an assembly line built engine and a blue printed engine.

Even the Cabots aren't polished by machine.