Trash Can Snap Cap
- Category: Bullseye Tutorial
- Topics: Safety S&W Model 41
After working with three “snap cap” gadgets for the Smith & Wesson Model 41 target pistol but finding each solution inadequate, I crafted my own design.
Since then, I have dry-fired hundreds of “shots” with it. It shows very few signs of wear and appears to be good for hundreds more. It is easy to install and remove with a small tool such as a miniature screwdriver. No dis-assembly of the pistol is required.
I call it the Trash Can Snap Cap.
Introduction
Here is my Smith & Wesson Model 41 target pistol. The slide is locked in the open (rearward) position and is ready for insertion of the Trash Can Snap Cap which is sitting next to the pistol in this photograph.
The Trash Can Snap Cap is a U-shaped piece of plastic that fits into the underside of the rear of the M41’s slide with the open end of the “U” cupped over the tail-end of the firing pin. When the trigger is pulled, the hammer strikes the solid bottom of the Trash Can Snap Cap instead of the firing pin. The firing pin does not move and, hence, neither the firing pin nor the breech face are touched.
Disclaimer
Although I have used this in my own dry-firing practice and it works well for me, I can’t speak for any number of factors including your construction abilities, the dimensions and appropriateness of any trash can other than the one in my shop for this purpose, whether or not your S&W Model 41 will adequately accept it, nor for anyone’s abilities to install and use it correctly. Nor can I verify that it has been installed correctly in your gun, nor that it remains in position in spite of oil, dirt or simple “wear and tear.”
I must, therefore, disclaim all warranties and responsibilities for the Trash Can Snap Cap for any purpose whatsoever.
“Once trash, always trash,” might be a good motto to keep in mind.
Use of the Trash Can Snap Cap is, therefore, completely at your own risk.
Materials and Tools
You will need the following items:
- Eldon Wastebasket, Black, 7 Gallon, 15"H x 10 1/2"W x 14 3/8"D (Staples, $3.49 plus tax on 12/30/2004);
- Ruler with 1/16" markings (or better); and
- Single-edge razor blade, Exacto knife or similar cutting implement.
Fabrication
Note: Do not use sandpaper or other abrasive because small bits of plastic might be left behind that could lead to a catastrophic failure of the pistol during subsequent live fire.
Here is my shop trash can. You can see the “bite” where I snipped out the material. One trash can should be good for several dozen.
To fabricate the Trash Can Snap Cap, remove a small piece of the lip around the top of the wastebasket as follows:
- Make two parallel vertical cuts down through the top lip of the wastebasket 5/16" apart and 3/8" deep; and
- On a line directly across from the bottom of the outer lip, cut and remove the (inverted) “U” shaped piece from the lip of the wastebasket.
The finished “U” shaped piece will be 3/8" deep with the left and right sides of the “U” 3/8" tall and the bottom of the “U” 1/2" wide.
Adjustment
Here is my finished model. It has been used for several hundred dry fires and, as you can see, it is holding up quite well.
Adjust the fit as follows:
- Make certain the S&W Model 41 is unloaded;
- Locate the firing pin in the slide and, thence, the rear of the firing pin which is in a cup-shaped depression on the underside of the slide;
- Trial-fit the Trash Can Snap Cap into that depression with the open end of the “U” cupped over the tail-end of the firing pin – the fit should be snug; and
- Check the clearance by slowly closing and opening the slide, and carefully trim the Trash Can Snap Cap so that the slide operates freely and the Trash Can Snap Cap remains fixed in position immediately around the tail-end of the firing pin.
- **Warning!**If the Trash Can Snap Cap slides backward away from the tail-end of the firing pin, it will become ineffective. The hammer will strike the firing pin and the front of the pin may be damaged. Actuate the slide several times and verify that the Trash Can Snap Cap does not move out of position (see photograph) immediately over the tail-end of the firing pin. If necessary, trim the height of the Trash Can Snap Cap so that movement of the slide does not cause it to be pushed out of position.
Installation
In this close-up, the Trash Can Snap Cap is fully installed. As you can see, it cups over the back end of the firing pin. Installation and removal are easier with a small tool such as a miniature screwdriver or tweezers.
To insert the Trash Can Snap Cap before dry-firing the pistol:
- Make certain the S&W Model 41 is unloaded;
- Lock the breech open and hold the pistol upside down so that the tail-end of the firing pin can be seen in the underside of the slide; and
- Insert the Trash Can Snap Cap into that depression with the open end of the “U” cupped over the tail-end of the firing pin – a small tool may be useful in seating the part fully.
The pistol is now ready for operation in “dry fire” mode.
Dry Firing
Note: When the Trash Can Snap Cap is correctly positioned, the hammer strikes it after a very brief movement. The sound this makes is quite different than if the gun is dry-fired against other protective devices. Listen for this distinctive sound because it assures you the Trash Can Snap Cap is working. Should the sound change, immediately stop and investigate. Verify that the Trash Can Snap Cap is correctly positioned and functioning before continuing.
To practice firing the pistol without ammunition (“dry fire”):
- Make certain the S&W Model 41 is unloaded;
- Make certain that the magazine (below) is empty;
- Insert an empty magazine and close the breech;
- Aim the pistol in a safe direction and pull the trigger;
- The hammer, when released, will strike the “bottom” of the “U”-shaped Trash Can Snap Cap instead of the firing pin; and
- Manually cycle the slide to re-cock the hammer and repeat as desired.
Removal
To restore the pistol for live-fire operation:
- Make certain the S&W Model 41 is unloaded;
- Lock the breech open and hold the pistol upside down as before; and
- Use a small tool to remove the Trash Can Snap Cap.
Rights
I crafted the Trash Can Snap Cap on December 30th, 2004. I published the directions (on that date) so that others may make their own Trash Can Snap Cap for personal use only. All such use is granted without royalty or fee of any kind.
Addendum
Ed Mini, edmini@inftek.com, found a source that works for older model 41s. He reported it to the Bullseye-L mailing list in May 2009. He is quoted here with permission.