Bob Smalser
Member
- Joined
- Apr 1, 2011
- Messages
- 26
Light, compact, accurate, and a natural pointer, the Colt 1903 Pocket Auto retrofitted with modern sights remains a great little pistol, but a difficult one to reassemble. The manuals I’ve seen either say “assembly is the reverse of disassembly”…which ain’t so…or not to disassemble beyond field stripping…or to take it to a gunsmith. Fine…except where does the gunsmith go for guidance? So when I got one of these in (as a bag of parts) to replace the slide safety, mainspring and trigger all broken or bent by an owner’s disassembly attempts, I thought I’d document how to reassemble one of these for the benefit of the next guy.
Field stripping is easy and you can find how to do it in books. I’ll only cover the parts internal to the frame. Here I’ve already installed the trigger, sear and disconnector, which are also straightforward. Also note that I’m using a rubber band to prevent the ejector from pivoting, which will make aligning the hammer easier.
The first parts to go in are the magazine catch and the sear spring. Both are straightforward…the magazine catch has a tenon that fits in a rectangular slot in the frame and the sear spring in the lower of two circular recesses in the frame sides. After installation, apply pressure to the spring with your finger to insure the three upper leaves engage the rear surfaces of the sear and disconnector and the lower leaf the magazine catch, and that all function correctly.
Note the upper circular recesses in the frame. These are for the mainspring, but are a sloppy fit until the mainspring is compressed, so watch the alignment as you proceed.
Slide the mainspring upward into the frame its position controlled the recesses. Note I’ve lightly mounted the pistol in a bronze-lined vise for stability.
Next I remove the mainspring temporarily to check the position of the sear before installing the grip safety. The sear must be tilted to the rear (push the lobes down) to properly engage the hooks on the grip safety in relationships shown in the diagram below:
Note how the three leaves of the sear spring (28) engage the sear (22) and disconnector (23), how the upper mainspring leaf (29) fits into the hammer slot above the pinned roller (18), and how the hooks of the grip safety (27) engage the rear lobes of the sear.
I slide the grip safety into the frame. Note that pressing against the mainspring will cause the bend of the mainspring to seat into the recess milled into the grip safety. I lightly greased both faying surfaces to make that easier.
Here I’ve seated the mainspring by applying pressure to the lower end of the grip safety, and am holding the assembly in place using a rubber band. Note the upper rear face of the grip safety rests firmly against the mortise in the frame. For future reference, this is the “cocked” position of the grip safety.
If instead, your efforts result in the grip safety ending in the “fired” or hammer-down position, the upper grip safety hooks rode over the sear lobes. You need to remove the grip safety, tip the sear to the rear and reinstall the grip safety so the end result is the “cocked” position.
An alternative to using a rubber band to hold the grip safety in position is to use a thin slave pin. Keep in mind that the more play there is in the bottom of the grip safety, the less pressure is required for the hammer to engage the upper leaf of the mainspring, which is the next step.
Continued…
Field stripping is easy and you can find how to do it in books. I’ll only cover the parts internal to the frame. Here I’ve already installed the trigger, sear and disconnector, which are also straightforward. Also note that I’m using a rubber band to prevent the ejector from pivoting, which will make aligning the hammer easier.
The first parts to go in are the magazine catch and the sear spring. Both are straightforward…the magazine catch has a tenon that fits in a rectangular slot in the frame and the sear spring in the lower of two circular recesses in the frame sides. After installation, apply pressure to the spring with your finger to insure the three upper leaves engage the rear surfaces of the sear and disconnector and the lower leaf the magazine catch, and that all function correctly.
Note the upper circular recesses in the frame. These are for the mainspring, but are a sloppy fit until the mainspring is compressed, so watch the alignment as you proceed.
Slide the mainspring upward into the frame its position controlled the recesses. Note I’ve lightly mounted the pistol in a bronze-lined vise for stability.
Next I remove the mainspring temporarily to check the position of the sear before installing the grip safety. The sear must be tilted to the rear (push the lobes down) to properly engage the hooks on the grip safety in relationships shown in the diagram below:
Note how the three leaves of the sear spring (28) engage the sear (22) and disconnector (23), how the upper mainspring leaf (29) fits into the hammer slot above the pinned roller (18), and how the hooks of the grip safety (27) engage the rear lobes of the sear.
I slide the grip safety into the frame. Note that pressing against the mainspring will cause the bend of the mainspring to seat into the recess milled into the grip safety. I lightly greased both faying surfaces to make that easier.
Here I’ve seated the mainspring by applying pressure to the lower end of the grip safety, and am holding the assembly in place using a rubber band. Note the upper rear face of the grip safety rests firmly against the mortise in the frame. For future reference, this is the “cocked” position of the grip safety.
If instead, your efforts result in the grip safety ending in the “fired” or hammer-down position, the upper grip safety hooks rode over the sear lobes. You need to remove the grip safety, tip the sear to the rear and reinstall the grip safety so the end result is the “cocked” position.
An alternative to using a rubber band to hold the grip safety in position is to use a thin slave pin. Keep in mind that the more play there is in the bottom of the grip safety, the less pressure is required for the hammer to engage the upper leaf of the mainspring, which is the next step.
Continued…
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