Building A 1911 From A Base Gun: Colt

Stainless new rollmark Series 80 1991A1.

This article is an update of a resource that I had on my old website when I still built 1911s to customer order.  A customer contacted me about the article, so I thought I would update the circa 2005 information and put it back out.  Please note the usual caveats of “your mileage may vary,” “everyone has their opinion,” etc., etc.  These insights are based only on my own research and experience, and if you have built a bunch of 1911s and have your own thoughts, by all means let’s discuss in the comments section.

There are a plethora of Colts to choose from, but they all share certain traits, both positive and negative, in regards to their use as base guns. Historically, Colts have had good quality small parts and metallurgy through all their different production runs. The prancing pony has history and character that no other 1911 can claim, and the traditional cosmetics are hard to beat for an elegant buildup.   One of Colt’s biggest problems has always been with quality control. Different vintages of Colts will exhibit machining and workmanship varying from exceptional to abysmal. Many Colts have very sharp edges that preclude their use in stock condition. Countless variations of special featured Government models have been marketed over the years, but the best candidates are those most in line with the traditional 5” 1911.

Circa 2005 production stainless 1991A1, Series 80, as new. Newer production models now come with rosewood grips.

Colt 1991A1: The current production new rollmark 1991A1 models are really pretty, and a return to Colt’s glorious days of nice looking polished guns. Forged frame, slide, slide stop; bar stock hammer, ejector, and extractor; and other high quality small parts make these new Colts a great deal. A suitable candidate for any level buildup. I prefer these over both the older matte finished, big 1991A1 rollmark guns and the various big “MK IV Series 80” rollmark guns.

Colt XSE: I love the cosmetics of the slide serrations and rollmarks on these guns. Depending on how much you want to do to one, they may have numerous “custom” features that are marginally executed and will be discarded on a full house gun. The earlier XSE guns had a proprietary dovetail cut for the front sight, as well as an unsightly and less than optimal downward angled beavertail grip safety. The front strap high cut is generally not what folks want, but it can be recut. Current production models are the best examples of the XSE, and if you want a gun with modern cosmetics (ie. angled cocking serrations, front and rear) and a Colt horsie, this is the best choice to consider.

Colt Gunsite Pistol: If this pistol had the same style rollmarks as the XSE and was under $1000 street price (it doesn’t and it is not), then it would be super cool. Its main attraction is that it does not have the Series 80 firing pin system. If you want one, these guns are out of general production but can still be found NIB on the secondary market as well as direct through Gunsite.

Colt Series 70, “B” serial number, small roll mark.

“G” series serial number Series 70, large roll mark.

Colt Series 70: You need to understand what to look for, or else you may end up with some buyer’s remorse. Colt’s QC wandered dramatically during the Series 70 runs. The earlier, big letter (70G prefix and G70 suffix serial numbers) rollmark guns tend to be more mechanically solid, but the mid to late production small letter guns (70B prefix and B70 suffix serial numbers) often exhibited serious machining flaws. The slides on the ”B” serial number guns very often had shallow or rolled radial lug cuts in the slide (see below), which preclude the correct cycling of the gun. There is no saving such a specimen, and it is to be avoided at all costs.

The Colt on the left might work. Or it might not. You won’t be able to save this slide.

Other issues common to all Series 70 guns include: lines/contours not machined straight, crooked or shallow slide rollmarks, thin or misshapen trigger guards, and thin or wavy front straps. A good specimen is a fantastic choice as a base gun, but it is also very easy to end up with a turkey with some holes or other machining cuts in the wrong place. It is currently safer to go with one of the new Colt Custom Shop Series 70s or other available reproductions that they are making.

Pre-Series 70 Colt Commercial, aka “C” series gun.

Colt pre-70 Commercial: Made in the 50’s and 60’s, most of these guns were examples of the best combination of metallurgy and quality control from Colt. Most are great base guns, but are getting very hard to find in condition that’s usable but not collectable.

New production Colt Series 70 reproduction.

Colt Custom Shop Series 70: The new production of the small letter Series 70, they have all the cosmetic appeal of the old guns, but without the mechanical problems. My preferred choice for a base gun for any type of buildup. A bit more money to start, but worth it if you want the Colt tradition.

Colt Custom Shop WW I and WW II reproductions: Same benefits as the Series 70 reproduction, but being limited run items, these are significantly more expensive. If you find a good deal or simply must have one built up, go for it.

Colt Gold Cup: I saved the worst for last. The Gold Cup makes a poor choice as a base gun or even a basic using gun. The staked front sight is notorious for flying off, and the Elliason rear sight’s roll pin is equally well known for breaking. The slide’s raised rib also complicates and limits your cosmetic options. Some holsters won’t accommodate the ribbed slide. The frame is cut for a nonstandard wide shoe trigger, which severely limits your aftermarket replacement options. The factory serrated front strap will also limit your front strap texturing options.

Before you go hunting for a base gun for your dream project, make sure to do your research so that you understand what you are buying.  Your gunsmith may also have some input for you as well, and they can likely help you determine the viability of your base gun.

This entry was posted in 1911, Weapon Modifications and tagged , by Hilton Yam. Bookmark the permalink.

About Hilton Yam

Hilton Yam is the founder of 10-8 Performance, LLC. He is a full time law enforcement officer in Florida with extensive experience working robbery and violent fugitives. He is currently assigned to firearms training and SWAT. He is a team leader as well as the lead instructor for his team, responsible for providing training in firearms, CQB, rappelling, defensive tactics, and team tactics. Hilton is also responsible for RDT&E of equipment. He has carried a 1911 extensively on duty, and has spent a great deal of time examining what makes the guns succeed and fail.

16 thoughts on “Building A 1911 From A Base Gun: Colt

  1. In terms of build quality and metallurgy, the current production Colts are the best in Colt’s history. Some small parts are MIM, but they are done well and will likely outlast the lifetime of the shooter. As for the Rail Gun, it is on par with the XSE feature-wise.

  2. A very well-known, long time ‘smith told me long ago, when looking at original Series 70 Colts was simple guide: “G” serial numbers are good; “B” serial numbers are bad.
    Funny, but an easy guide. All of my Colts are NRM Series 70 guns. An added bonus is the availability in stainless.
    I printed and saved your original series from the other forum on building Colts; looking forward to the update. Seems like parts are still getting better – look at the various parts like safeties, etc. now done in barstock, a serious upgrade from MIM.

    • When done correctly, MIM is just fine. SA uses Metal Injection Molding for all of their slide stops, including the ones in their Professional model and I have yet to ever see one break. On the other hand, I have seen quite a few popular bar stock thumb safeties break at the flange/pin interface.

    • That’s funny, as I’d also use the “G for good, B for bad” reminder, but was lambasted by some other smiths for daring to say such a thing. I’m over it, but that is indeed a simple way to remember it. With the ready availability of the new Series 70, there is no real reason to roll the dice and use a vintage Colt for a build.

  3. Gentleman,

    Any thoughts on the recent CCG Talo model? I recently examined several examples and they seem like a really nicely built firearm though the slide to frame fit seemed to vary between examples.


    • They are a modified 1991A1, so any observations about them fall in line with those base models. They seem nice enough, with a few added features.

  4. Still don’t own a 1911…. but I still love reading this stuff. Great read.

  5. Great reviews!! I appreciate you doing that. I have decided on a Colt CCG myself. My only problem is finding one. I have contacted all my local Colt dealers, and looked online. Colt says they produce them usually every other month, but cannot release their distributers. Any ideas? Thanks

  6. Can you comment on where the Colt Series 70 9mm guns fall in the range of QC problems? Most I’m seeing have an L prefix, but I have seen some with the small and the large lettering. I’m interested in buying one as a base gun for a competition/range shooter build.

    • You are better off having your smith put something together from scratch. I had a few of those guns and got rid of all of them as the slide radial lugs were poor on each one. There is no saving one with a bad slide. With those costing upward of $1000 for the base gun alone, you are wasting a ton of money as all you’d salvage from a PERFECT specimen is a slide, frame, and a few pins. The slide then may or may not sit squarely and tightly on the frame. Had a few of those where the frame ways were cut off center in the slide. In case I am too subtle here….don’t use one.

      • Thanks, Hilton! I really appreciate the feedback and lack of subtly. Go or no go in this case is exactly what I needed.

  7. Great article! What do you think about the relatively new 5″ Government Wiley Clapp edition?

  8. Also, do you have any idea what MIM parts are in the Wiley Clapp Gov’t? Or which parts should have work done for increased reliability? Thanks!

    • As mentioned in my Colt Reliability Test article elsewhere on this site, the Colts come generally pretty reliable (for a 1911) right out of the box. The MIM parts Colt uses are of pretty high quality. In fact, I have a stash of MIM Colt sears that I use to replace the crappy sears that come on Kimbers and “Loaded” grade Springfields. The MIM Colt disconnectors are also pretty darned good. From a reliability standpoint, I wouldn’t get wrapped around the axle about replacing Colt small parts. Shoot the thing, do the extractor test, and address issues as they arise.

Comments are closed.