Tuesday, June 26, 2007

Rebuilding a Springfield Mil-Spec 1911

My friend Kommander bought his first 1911 about three years ago; a Springfield Armory Mil-Spec 1911; and since then he's put at least 10,000 rounds through the thing.

It's a perfectly good gun. It's always been reliable, but it was never very accurate, and it just wasn't quite "right". He did use it as his primary carry gun for much of that three year period, but he was never quite satisfied with it. I did a trigger job, and installed a new extended safety for him last year, and that helped a bit; but it still wasn't where he wanted it to be.

Well, a couple months back for his new gig as an armored car driver and guard, he picked up a new carry gun. His employer required that he have a DA/SA in 9mm or .40; so he bought himself a Sig P229 (on my recommendation as well as the recommendation of almost everyone else he talked to) ; and man, he was just blown away by it.

He like the feel in the hand, the ergonomics, the ease of recoil control; and mostly he really liked the accuracy. He was used to 4" rapid fire groups at 10 yards with his 1911, and he went down to under 2" groups at 10 yards with the SIG. He never really could get a good doubletap with the 1911, and the holes were touching with the SIG.

Well, we figured out a while back that part of the problem he had shooting the 1911 was his grip; he was holding the gun way too low, and without proper weak hand support. We've been working on correcting that, and he knows HOW to do it, but it's still not natural to him.

The other part of the problem though is the gun itself. Let me illustrate first with a stock Springfield Mil-Spec (which isn't actually a GI.45 - they have a model that is pretty close to the original actually called the GI - it's just their lowest end stripped down 1911 model)

Firstly, the grip thing.

Because of its grip shape, the SIG pretty much cannot be gripped improperly, while still keeping control of the weapon. The shape of the backstrap just kinda naturally puts your hand in the right place. The Mil-Spec 1911 on the other hand has an extended but not deep or flat grip safety tang, and it's quite uncomfortable for him to get a proper high and deep hold on the gun.

This isn't quite the original 1911 or 1911-a1 grip safety, it's a bit longer; but it's similar; and like millions of shooters before him, he cant get the proper high and forward grip established easily, and when he does the grip safety tang abrades his hand.

The Mil-Spec also has a conventional spur hammer, and with the high forward hold, again as millions before him; he gets hammerbite.

Finally, like most springers; the Mil-Spec has a curved serrated mainspring housing with an integrated lock that Springfield calls the ILS (integrated locking system). The serrated mainspring housing doesn't give very good grip (though he prefers the arched housing to the flat that most shooters prefer - as do I actually); and just on principle he doesn't like lawyer locks.

Oh, and after three years of daily carry, the original Parkerized finish was more than a little bit worn; in fact in some places there wasn't really any finish left at all.

Thankfully, we're talking about a 1911; and the wonderful marketplace has provided solutions for all of these problems. A few hours worth of work, and a $150 order from Brownells later; this is what he's got:

Step one - the refinish job:

Visually speaking, the biggest change was certainly the refinish job. It was also by far the most work, and the most difficult thing for a novice to do at home.

First, he completely stripped the pistol to the bare frame and slide (well... he left the sights on), then baked the pistol in the oven at 200 degrees for 45 minutes before completely degreasing the pistol. The heat makes the accumulated grease, oils, and crud leech out to the surface. Then after the pistol had completely cooled, he did the whole thing one more time just to make sure.

Before you refinish any part it must be COMPLETELY free of any and all oils or contaminants, including those from your bare skin; so use a good de-greaser, and wear gloves.

Next step, lightly hit the frame and slide with 000 (or finer) steel wool, and scrub every bit of both with de-greaser and a wire brush.

Are you getting the point that the gun has to be absolutely clean?

Next, fashion a heat resistant means of suspending the frame and slide (and any other parts you're going to re-finish) that doesn't mask out any area that you want to paint (most people use wire coat hangars or something similar); and deliberately mask out any areas you DON'T want to paint with a residue free masking product (blue painters tape is close enough).

It is important to note here that even if a coating product states you can use it on all internal parts, and that it goes on very thin etc... that it's still not a good idea to coat your barrel, the inside of your bushing, the locking lugs inside the top of the slide etc...

Basically, unless you plan on cleaning and polishing them off later, you should mask off any metal bearing surfaces. If your gun isn't TOO tight, you can probably get away with coating the lugs and rails, and then just shoot the gun (and be prepared for it to jam up a bunch of times) until the coating wears off; but I'd really prefer not to do that on the barrel lugs or feed ramp.

When I say "mask off any bearing surface", what I mean by that is any surface that has a metal to metal contact, and takes pressure and friction. Just any surface with metal to metal contact is different. The area under your thumb safety has metal to metal contact, and you want to coat that for example.

Make a clean, breeze free and dust free (but properly ventilated) area where you can spray the parts. They sell cheap portable spray boxes for doing this, but you can make one yourself from cardboard or plywood, and plastic sheeting.

There are several different coating technologies and products out there for the home user; the same basic prep steps I've described above apply to almost all of them (though some require more prep work); but you should follow manufacturers directions.

Kommander chose a rattlecan GunKote from Brownells (it also comes in a version for airbrushing) because it's relatively cheap, and very easy to apply without special tools. You can get a better finish by applying with an airbrush, but I think the rattlecan version does a good enough job for a carry gun.

One nice thing about GunKote; Brownells has free videos up about how to apply it (and their other spray on finished by the way), so you know what you're getting into before you buy it:

Metal prep
GunKote application

Those are flash videos hosted on youtube by the way; so if you can't get youtube or flash, sorry about that. They also sell a DVD with the instructions for a nominal fee.

The basic prep process for GunKote is pretty simple. Clean the part, then sandblast it with aluminum oxide. Gunkote should really be applied over sandblasted surfaces; but if your frame was media blased then parkerized, as the Mil-SPec was, then you should get decent results without re-blasting. Finally clean and degrease it again, and heat the parts up to between 100 and 120 degrees to prep for coating.

To coat, you want to go ahead and spray a light tack coat (just a light but uniform dusting of finish) over the whole piece, then hit it with a heat gun on low or a hair dryer on high to get the coating to flash over (when the surface gets a skin of lightly cured finish over it). Then repeat for a second tack coat, and hit the heat gun again.

What this does is effectively act like a primer for the finish coats. The finish coat sticks to the just barely there and just slightly dried coating much better than it does to bare metal. This helps give you a more uniform finish, and to avoid drips and runs.

Apply a third, full coat; and be careful to coat only as heavy as you have to, to avoid runs or drips; and again hit with the heat gun. Finally, apply a fourth finish skim coat (meaning the lightest coat possible that fully covers the piece), again being careful about drips; and hang it up to dry for about a half hour.

Once you've let the piece dry a bit, you place it into a preheated oven a 350 degrees for an hour; and then shut off the oven and let it cool.


Seriously, this coating is going to outgas very nasty stuff as it cures; and it gets onto the metal permanently. You wouldn't want to eat food that had been sprayed with it; you don't want to use your food oven to cure it.

Kommander did, but the last time he used his oven was several months ago, and he accidentally set it on fire so...

You can make your own curing oven using a metal box, firebricks and/or kaowool, a store bought( or junk yard bought, or pawn shop bought) heating element, a thermostat, and a power supply. You can get most of those things from a salvaged toaster oven or radiant heater.

Hell, if you've got a spare 220 outlet, you can go buy a cheap old oven from the paper or craigslist or summat. You probably won't even pay $50 for it.

This was Kommanders first try at coating a gun, so it's a bit uneven. He got a couple runs, and had to sand them out and re-spray; so the slide and frame aren't quite uniform. When he's sure he's completely done messing with the gun, he's going to re-sand and re-coat the gun one more time just to even things out.

That said, I think it looks pretty good. Certainly a heck of a lot better than worn off Parkerizing (those shiny spots and streaks are lubricant, not problems with the finish).

He topped off the new finish with a set of Phillipine Mahogany double diamond checkered grips, that I'd say also look pretty darn good.

Step two - Mechanical Accuracy:

So, finishing addressed, we move on to accuracy (and the ergonomics of the gun, which have been adversely effecting it; but that's next section).

The Mil-Spec springer isn't an inaccurate by any means; but it is Springfields lowest end production gun. As such, the manufacturing tolerances are a bit looser, and the standards are just a bit lower.

Now, the Mil-Spec uses the same frame and slide forgings as Springfields' higher end loaded line; but on the Loaded line, they do fine final machining and surface prep in Illinois, on the Mil-Spec, they are done at IMBEL in Brazil, to a slightly lower standard (Kimber and Colt do the same thing by the way, so don't think it's just Springfield).

The same goes for the barrel and bushing. Springfield loaded guns use a Nowlin designed and specced barrel and bushing; and they finish them to Nowlins standards, in the US. The early loaded line guns actually had a Nowlin branded match barrel in them in fact. On the Mil-Spec and GI, the barrel and bushing are lower specced units, made in Brazil to a looser standard.

All of this is just fine for reliability; they are still good quality well made parts; but to save on cost, they aren't very closely fitted. They also aren't timed for optimum performance.

The single biggest determinant of the inherent accuracy of a semi-auto pistol is how consistent it's barrel lockup is. In a 1911 the barrel locks up in the rear at the lugs, and in the front at the bushing. The tightness of the lockup is determined by barrel to bushing fit, the fit of the barrel lugs into the slide lugs, and the fit of the slide rails to the frame rails. The timing of the lockup is determined by the tilting link. Both of the above are effected by the geometry of the rails, lugs, and bushings mechanical mating.

In a well fitted pistol, there should be very little play in between the barrel and bushing; and when the barrel is dry fitted into the slide lugs, there should be no more than about 1/64th" of motion from front to rear. The rails should slide freely and smoothly with no biding, and allow for a very little side to side play; but there should be no (or a very tiny amount at worst) vertical play.

In all three cases, a little play is necessary or the weapon wont lockup properly, unlock, or cycle when dirty; but as little as play possible while maintaining reliability is the goal.

On Kommanders gun, lockup was good, but a bit loose. The frame and slide rails had decent fit; but there was a lot of play between the barrel and bushing; and a bit more play in the lugs than I like to see. Also, although the gun was timed well enough to be safe and reliable; the link was a bit shorter than I would have liked for optimum lockup.

They sell matched "drop-in" match grade barrel and bushing sets, and link timing kits (which have three or four different length links); and I recommended he pick up one of each. He decided to get a new drop in bushing and the link kit, but to save money and time (drop in barrels are never really drop in, they always need some degree of fitting; unless they are made way too loose in the first place, in which case why bother?) he wanted to try and keep his existing barrel. I told him he would see some improvement, but that his barrel lugs just weren't a good enough fit (the slide lugs seem well cut and finished) to get any real accuracy out of the gun.

So, he put in his new bushing, went out and shot a bit; and it definitely made a difference, but not enough of one.

I'm gracious enough not to mention the obvious.

His next step is going to be to order a new match barrel (probably an Ed Brown as well)... and really he should just order the matched set, and I'll fit them for him. Barrel fitting of high quality parts (and Ed Brown certainly qualifies) really isn't that big a deal if you have the right tools and experience.

...I'm not going to hand lapp the lugs and bushing for him though; if he wants to do that he's welcome to spend the couple hours of mind numbing sloppy work it takes on his own.

It's good for the soul.

Step three - Ergonomics:

Now for the other changes you can see, and he can feel; the ergos. The fact is, if a gun isn't comfortable you wont shoot it well, it won't be accurate, and you want want to carry it (or shoot it for that matter).

First step hammer and trigger. I put a good quality (Ed Brown) sear, disconnector, and extractor in the gun when I did the trigger job on it a few months back; but Kommander wanted to keep the original hammer because he thought the rowel or skeleton hammers looked silly without a beavertail. I also changed him out to a longer solid Ed Brown trigger with overtravel adjustment (the original trigger was the super short 1911-A1 spec as pictured in the Springfield pic above); and a WIlson extended safety.

Unfortunately, with the new trigger and sear, the old MIM factory hammer was just not up to the job. The wear surfaces of the old MIM hammer wore in a bit too much against the harder sear, and the edges of the hammer hooks were starting to round. Combined with the heavier long, solid trigger, the pistol was occasionally getting trigger bounce (this is where the inertia of the trigger in recoil recovery, or when you drop the slide, makes it bounce against the sear and trip it).

So, to fix this, and to help with the hammer bite problem mentioned above, he did a full Wolff spring replacement (for the trigger bounce problem you only need to replace the sear spring, but the recoil spring was wearing out anyway) and put in a new Ed Brown speed hammer. This has the added benefit of reducing lock time, which improves accuracy.

The geometry of the hammer is good; and with the new parts in place, but with no additional fitting; the trigger pull is actually very crisp, with no creep, slop, stacking, or grit. The only issue is that it's a bit heavy at just about six pounds, but he says hes' fine with that, so we aren't going to mess with it.

Next step, reshaping the backstrap for better grip.

With some guns, reshaping the grip is a major chore, but in a 1911 it's a matter of two parts: the mainspring housing, and the grip safety.

Kommander wanted a checkered mainspring housing, and to add a beavertail; so he ordered a Wilson zero fit drop-in beavertail grip safety, and a Smith and Alexander arched checkered mainspring housing (I have the same housing on a couple of my guns) from Brownells:

Here's a better pic of the grip safety:

The only problem with those drop in grip safeties, is that in order to really be zero fitting needed; they need to leave a very large clearance for the grip frame; because different manufacturers have used different lengths and shapes of grip safety, and have shaped the rear of the frame slightly differently over the years; as you can see here:

They do make drop in models that will fit close for specific manufacturers models, but they still leave a fair bit of a gap. What he didn't realize was that the Springfield Mil-Spec you can fit a beavertail from a Springfield Loaded pistol with minimal machine work; because the frames are machined on the same fixtures (there are also several manufacturers that sell beavertails cut to that radius).

All you need to do is radius the horn (any die grinder or bench grinder with a fine wheel will do, for less than 1/8" material removed. Theres a jig from Brownells if you dont want to freehand it), then a little bit of final fitting, and it will fit quite nicely without that big gap (since he was doing a bake on anyway).

That big gap by the way chews up your hand; because the edges are crisp and sharp, unless of course you relieve the edges of the so called "drop-in" grip safety anyway... so there's really no point to the zero fit stuff for this gun (other guns may be different).

Now, the only thing it's missing to be 100% for him are night sights ( and unfortunately they are going to need a trip to the gun smith to mill a couple dovetails), and the new, better, barrel.

So Kommander is generally quite happy with the rebuild job. It's got a BIT more tweaking to do, but he's still spent a fair bit less than a brand new Loaded would have cost him, and now he's got a gun fitted and finished to his specifications; and the pride of having done it himself.

Once he's completely done it will have cost him just about the same as a Loaded (or maybe a bit more); but then he'll have a better gun, because he will have replaced all the factory hard parts with hand fitted premium components (no marshmallow immitating metal). Oh and none of those evil forward grip serrations.

Not bad I'd say.