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1911 Action Job
by Roy Seifert

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Disclaimer:  This article is for entertainment only and is not to be used in lieu of a qualified gunsmith.  Please defer all firearms work to a qualified gunsmith.  Any loads mentioned in this article are my loads for my guns and have been carefully worked up using established guidelines and special tools.  The author assumes no responsibility or liability for use of these loads, or use or misuse of this article.  Please note that I am not a professional gunsmith, just a shooting enthusiast and hobbyist, as well as a tinkerer.  This article explains work that I performed to my guns without the assistance of a qualified gunsmith.  Some procedures described in this article require special tools and cannot/should not be performed without them.

Warning:  Disassembling and tinkering with your firearm may void the warranty.  I claim no responsibility for use or misuse of this article.  Again, this article is for entertainment purposes only!

Tools and firearms are the trademark/service mark or registered trademark of their respective manufacturers.

I recently purchased a Rock Island Armory 1911A1-45 FS GI made by Armscor of the Philippines .  This is a WWI military pattern 1911 clone in .45 ACP with a parkerized finish.  It has a few modern improvements such as a throated chamber, polished feed ramp, and roll-over notch.  It got great reviews on the Internet and the price was right.

The trigger let-off was heavy at 6 1/2 pounds and was long with a lot of creep.  This was caused by rough cut hammer and sear engagement surfaces and long hammer hooks.  The hammer hooks measured 35-thousandths of an inch; much too long for a crisp trigger.  So, I needed to reduce the length of the hammer hooks and polish and hammer and sear engagement surfaces.

CAUTION:  Working on hammer and sear engagement surfaces requires special tools and cannot/ should not be performed without them!  Without the use of these special tools the surfaces can become rounded and uneven and could cause the firearm to become unsafe.


Many years ago I purchased a Bob Marvel 1911 Auto Sear & Hammer Jig from Brownells.  This jig allows me to work on both the hammer and sear; other jigs on the market would only allow me to work on one or the other. 

I also purchased the recommended medium-fine and extra-fine ceramic stones from Brownells.  These stones are perfectly flat and square and are the right tool for this type of work.  The sharp edges fit into the corner of the hammer hooks so the entire surface gets polished.

To reduce the length of the hammer hooks I used a Power Custom Series I Stoning Fixture that I also purchased from Brownells along with the 45 adapter.  These can also be purchased from MidwayUSA.  For cutting I used a 220-grit silicon-carbide polishing stick I purchased from Boride Engineered Abrasives.  Their Gunsmith Action Kit contains a number of different stones and grits I regularly use for gunsmithing work.

Reducing Hammer Hook Length
The instructions that came with the Marvel jig stated that the hammer hooks should be reduced to 0.018” – 0.020”.  I decided to reduce the length to 0.025” and work from there. 

I removed the hammer strut pin and hammer strut from the hammer.  I installed the 45 adapter onto the Power Custom Series I Stoning Fixture then installed the hammer onto the adapter with the hooks pointing up.  I used the 220-grit silicon-carbide stick coated with gun oil and polished the hooks until they measured 0.025”.  The jig ensured that the ends of the hooks were even and square.  I went very slowly here and measured often.  Because of the coarse stone it only took about 10-15 passes to get the proper length.

I installed the hammer onto the Marvel jig following the instructions.  I used the black ceramic stick to perform the initial polishing, then finished with the white ceramic stick.  Ceramic sticks use water as the cutting/cleaning agent; I never use oil on a ceramic stick.

Next I disassembled the frame and again following the Marvel jig instructions, installed the sear onto the jig.  When adjusting the height if the sear above the top of the jig I use a 0.0015” shim under the front of the polishing stick and raise the height adjustment until the sear is just touching the bottom of the stick.  If the sear is too high the angle of the sear would be changed.

I used the black ceramic stick to polish the sear so it was straight across.  Many sears I have polished were cut crooked, but the jig ensures it is cut straight.  After using the black stick, I used the white ceramic stick to final polish the surface.

Finally I cut the break-away angle on the rear of the sear so that about 0.020” of engagement surface was left.  This provides a nice, crisp trigger pull.

I used a toothpick to apply a very small amount of Brownell’s Action Lube Plus® to the corner of the hammer hooks before reassembling the gun.  After the gun was assembled I cocked the hammer, applied pressure to the rear of the hammer with the thumb of my left hand, and pulled the trigger.  This is called “pushing the hammer” which helps the hammer and sear seat together quicker.  Finally I allowed the slide to slam home with no magazine in place to test if I had any hammer follow.  This is a very unsafe condition which usually results in having to replace the hammer, sear, or both.  I did not have any hammer follow.  By the way, this should not be performed very often as it can damage the slide and frame.

The sear now breaks crisply and cleanly at 4 1/2 pounds with no grit or creep.  The investment for tooling for jigs and stones can be fairly expensive, but the results make the investment well worthwhile.  If I had reduced the length of the hooks to 0.020 I could have reduced the pull weight even farther.  I have a couple of 1911’s that I build from all hand-fitted parts and their sears release at 2 3/4 pounds.


   © Copyright 2011 Roy Seifert.