How to check the angle on a 1911 sear?

nathanl · December 7, 2014, 11:13 AM

I recently purchased a wilson combat value line sear and hammer. They say that the angle on the sear is already cut and it will just "drop in" I know thats not always the caseso is there a way to check if the hammer and sear are matching up correctly? If any fitting has to be done it's going to a gun smith I would just like to know if there is a way to check so that I dont spend money paying a smith to say it fit together fine and he didnt even have to do any fitting.

polyphemus · December 7, 2014, 12:45 PM

To check sear angles and hammer ledge engagement.You need the fixtures
available from gunsmith tool suppliers.
Blue prints showing full dimensions for all M1911 parts are also available and easy to obtain.

Dixie Gunsmithing · December 7, 2014, 02:33 PM

This may help you too, it's the Army Technical Manual for armorers on the 1911. I know it has most all the jigs and fixtures used in repairing them in the shop.

TM 9-1005-211-35 Pistol, Caliber .45, Automatic, M1911A1:

https://archive.org/details/TM9-1005-211-35

Also, you can easily make a sear jig. Just measure the hole centers for the hammer and sear pin, then drill a small steel block with those centers, using the correct hole sizes to match the pins. Buy original pins to use in the jig, as they will fit the hammer and sear correctly. After the block is drilled, and the pins tapped in, slip the hammer and sear over the pins, and visually check the fit. Hone the sear until it has a positive engagement, in other words, when the sear is moved forward out of the hammers notch, it should barely move the hammer backwards. Last, check it in the gun, and measure the trigger pull. If the assembly shows either neutral or negative hammer to sear engagement, it is unsafe, so correct the angle(s).

The best way to measure the hole centers, is to place the pins in the holes on the frame, and measure across them with a dial caliper, then subtract 1/2 of each pin diameter from this measurement. The sum of the subtraction is the hole centers. If you have a frame print, you may get the centers from it.

I would advise looking for a DVD on these, by AGI, for gunsmithing the 1911.

phudd · December 7, 2014, 03:00 PM

December 7, 2014, 11:13 AM	#1
nathanl Junior Member Join Date: November 30, 2014 Posts: 6	How to check the angle on a 1911 sear? I recently purchased a wilson combat value line sear and hammer. They say that the angle on the sear is already cut and it will just "drop in" I know thats not always the caseso is there a way to check if the hammer and sear are matching up correctly? If any fitting has to be done it's going to a gun smith I would just like to know if there is a way to check so that I dont spend money paying a smith to say it fit together fine and he didnt even have to do any fitting.

December 7, 2014, 03:00 PM	#4
phudd Member Join Date: November 16, 2014 Location: North Carolina Posts: 25	__________________ https://www.youtube.com/watch?v=0joaQpLzVjs

December 7, 2014, 12:45 PM	#2
polyphemus Senior Member Join Date: June 24, 2012 Posts: 1,055	To check sear angles and hammer ledge engagement.You need the fixtures available from gunsmith tool suppliers. Blue prints showing full dimensions for all M1911 parts are also available and easy to obtain.

December 7, 2014, 02:33 PM	#3
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	This may help you too, it's the Army Technical Manual for armorers on the 1911. I know it has most all the jigs and fixtures used in repairing them in the shop. TM 9-1005-211-35 Pistol, Caliber .45, Automatic, M1911A1: https://archive.org/details/TM9-1005-211-35 Also, you can easily make a sear jig. Just measure the hole centers for the hammer and sear pin, then drill a small steel block with those centers, using the correct hole sizes to match the pins. Buy original pins to use in the jig, as they will fit the hammer and sear correctly. After the block is drilled, and the pins tapped in, slip the hammer and sear over the pins, and visually check the fit. Hone the sear until it has a positive engagement, in other words, when the sear is moved forward out of the hammers notch, it should barely move the hammer backwards. Last, check it in the gun, and measure the trigger pull. If the assembly shows either neutral or negative hammer to sear engagement, it is unsafe, so correct the angle(s). The best way to measure the hole centers, is to place the pins in the holes on the frame, and measure across them with a dial caliper, then subtract 1/2 of each pin diameter from this measurement. The sum of the subtraction is the hole centers. If you have a frame print, you may get the centers from it. I would advise looking for a DVD on these, by AGI, for gunsmithing the 1911.