EGW Sear Spring

Improving on Perfection?

Reviewed for M1911.ORG by Harwood Loomis

As I wrote in a previous review of another EGW product, Evolution Gun Works (EGW, for short) is a small shop that has developed a large reputation among people who know 1911 pistols. Among other offerings not available anywhere else, EGW offers custom-made barrel bushings, to turn any existing barrel and slide into a match fit configuration. Our previous review was of their “trigger job in a box.” This time around, it’s a perfect complement to the “trigger job in a box”: the EGW Evolved Sear Spring.

When we reviewed the EGW Ignition Set in late 2011, the sear spring that came with the kit was a Colt sear spring. At the time, I wrote, “In this writer’s opinion, there is no better sear spring available for the 1911, anywhere, at any price.” Nothing has come along in almost nine years to cause me to revise that opinion. Can the new EGW Evolved Sear Spring unseat the long-time champion? Read on to find out.

No championship match is complete without a weigh-in. Let’s start with a look at the contenders, and a visual “tale of the tape.”

A generic sear spring (brand unknown) on the left, a new Colt sear spring in the center, and the EGW Evolved Sear spring on the right

In the photo above, several differences among the three sample springs should be immediately obvious. The generic spring on the left visually appears to follow the original Ordnance Department blueprint, at least in form. (I didn’t check it for length.) Each of the three leaves continues at the same width for its entire length. Where my generic sear spring didn’t follow the Ordnance Department print is that the center leaf should have a .01”x.01” chamfer on the face toward the disconnector, and the right leaf should have a .01”x.01” chamfer on the face toward the grip safety. These two tips on the generic spring were cut square and left slightly rough.

A closer view of the three springs, with the generic sear spring on the left, the new Colt sear spring in the center, and the EGW Evolved Sear spring on the right

These differences are spelled out graphically in a set of line drawings that appear on EGW's web site, and we reproduce them here with permission from EGW:

For test fitting the Evolved Sear Spring, I used my everyday carry pistol, which is a Colt Lightweight Officers ACP. The sear spring in the pistol appears to be almost identical to the generic sear spring of unknown brand that I found in my parts drawer. Both, as mentioned, appear to conform fairly closely to the Ordnance Department blueprint for the M1911 sear spring, except that the spring in the pistol has the chamfer in the locations called for on the blueprint. It does not, however, look like the Colt sear springs I have purchased in recent years from Brownell’s. The problem is that I bought the pistol used, so I have no way of knowing if it’s the original sear spring or a replacement. Whatever it is, it produces a trigger pull that breaks at 4¾ pounds, which I consider to be about perfect for a single-action self-defense handgun. That, then, established the baseline for my further investigations.

The Colt Officers ACP test bed pistol

The unknown generic sear spring has a center leg (the leg that bears on the disconnector) that is visibly longer than the other springs. This can be seen in the photo above by following the graph paper grid lines, and it can also be seen in photos of the springs when installed in the pistol.

The original sear spring in the Colt Officers ACP

The generic sear spring in the Colt Officers ACP

The left leg of the original sear spring falls almost perfectly halfway up the left leg of the sear, and the center leg of the original sear spring falls fairly low on the disconnector ramp. The left leg of the generic sear spring falls slightly higher on the left leg of the sear, and the center leg falls much higher on the disconnector ramp.

I then put the new Colt sear spring into the pistol. The left leg of this spring falls just below the midpoint of the left leg of the sear, and the center leg of the Colt spring falls quite low on the disconnector ramp.

The new Colt sear spring in the Colt Officers ACP

Lastly, I put the EGW Evolved Sear Spring into the Colt. The left leg of the EGW spring engages the left leg of the sear very high, and the center leg of the spring falls low on the disconnector ramp.

The EGW Evolved Sear Spring in the Colt Officers ACP

The photos also show how the new Colt sear spring has the left and center legs narrow for most of their length, flaring out to full width a short distance before the tips. The EGW Evolved Sear Spring has these legs narrowed even more than the new Colt spring, and they return to full width even farther up toward the tips.

EGW explains that, with so many companies making 1911s today, as well as hobbyists making their own from unfinished receivers, it is becoming more common to find the sear pin hole incorrectly located, or (even more common) the sear spring locating slot cut in an incorrect location. To compensate for out-of-spec frames, the Evolved Sear Spring has the left leg made .030” longer than the standard 1911 sear spring. The narrowed legs and reduced height tips are for the purpose of reducing weight in the spring, making the action more responsive to accomplished shooters.

What’s the bottom line?

Unfortunately, as I write this review I am in a state whose governor has issued an executive order calling for everyone who is not working in an “essential” business to stay at home except for trips to the grocery store or pharmacy. My town has a local ordinance that strictly prohibits the discharge of firearms anywhere in town. This means that I can’t take the pistol to the range and see how the EGW Evolved Sear Spring performs in live fire. I did put each of the sample springs into the pistol and test the trigger pull weight over an average of several pulls for each, using an RCBS analog trigger pull scale. The unknown brand, generic sear spring produced an ugly 6⅜ pounds. Fortunately, things improved after that. Straight out of the bag, both the new Colt sear spring and the EGW Evolved Sear Spring produced trigger pulls of exactly 4 pounds. Many people would consider that to be ideal. For an IDPA competition pistol I would agree, but I prefer just a bit more pull weight for a carry pistol. Adding pull weight is easy with the 1911—a very slight amount of bend to the left and center legs and it should be good to go.


The M1911 pistol “platform” is now 109 years old. Innumerable self-styled experts have repeatedly declared it to be obsolete, yet today there are arguably more different companies and custom gunsmiths making 1911 pistols and parts for the 1911 than for any other firearm, with the possible exception of the AR-15. If the 1911 is obsolete, it seems that a lot of people didn’t get the memo.

The M1911 was designed for one purpose: to be a combat weapon. Pinpoint, national match accuracy was far less a concern than reliability under harsh, battlefield conditions. In the pursuit of enhanced accuracy, many people and many companies have devised “improvements” to the original John Moses Browning design. Some of these improvements have proven to have merit; many of them have not. I approach any deviation from the original design with a great deal of caution and skepticism. I am not an advocate of change for the sake of change. Different is not always better; sometimes, different is just … different.

Over the course of a number of years tinkering with 1911s, I have had some unhappy results using generic sear springs, and I have had a couple of truly disastrous experiences using “brand name” sear springs. Long ago, I settled on genuine Colt sear springs as the only viable choice for reliability and proper performance. I’m not alone in this; a number of custom gunsmiths also rely on Colt sear springs, and EGW used Colt sear springs in their competition ignition kits that we reviewed here in 2011. The bad news is that it is becoming more difficult to source genuine Colt sear springs. Colt has discontinued direct sale of replacement parts to consumers, and Brownell’s seem to have trouble obtaining Colt parts these days. As I write this, I just checked Brownell’s web site, and the Colt sear spring is out of stock.

Therefore, it’s good to have a second source for a quality sear spring. Based on what I can see, the EGW Evolved Sear Spring is a good substitute for the Colt sear spring and, if you are unfortunate enough to be working on a frame that’s dimensionally out-of-spec, the EGW sear spring may be your salvation.

My only reservation is that EGW has left the tips of the legs cut square. The Ordinance drawing for the M1911 sear spring calls for a .01”x.01” chamfer on the tips of the center and right legs of the sear spring. I wish that EGW would put that chamfer in place when making the springs, but it requires only a few passes with a fine stone or a jeweler’s file to create the chamfer so the lack is not a show-stopper.

The Ordnance Department drawing for the M1911 sear. Note the detail calling for the chamfer

Overall, I think the EGW Evolved Sear Spring is a solid product that may become the first choice for a number of 1911 mechanics.

You may discuss this article on our forum’s site.

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Evolution Gun Works, Inc.
52 Belmont Avenue
Quakertown, PA 18951

Tel: 215-538-1012
Fax: 215-538-1016

MSRP: $18.00 (2 pack) / $80.00 (10 pack)