Dry Fire Device - Patent Pending

[NugginFutz]

Sent info and pmt. Great job, Bro.

[ejkoechling]

Payment sent. Thank you

[CPT.CRAZY]

Do you still have some available?

[dmsims21]

Do you still have some available?

I have about 80 left.
If you are interested, just send me a PM or email with your address.
I am taking payment through PayPal.
My email is dmsims21@gmail.com

Thank you very much.
David Sims

[rasp65]

Thanks dmsims21 I look forward to receiving it. From what I have read from the people that have T&E'd it I believe you may have a winner here.

[dmsims21]

I am sorry to say that there is an issue with the Dry Fire Device. There has been one customer who could not get the device to lock into two different lowers.
The slot in the device for the mag catch is too short. With a certain combination of tolerance stack up, the mag catch on the lower will not properly seat into the slot on the device.

I discovered that I messed up the slot location. Pmags have a longer slot that GI mags, because the Pmags have larger radii in the corners.
I mixed measurements from the two mags and started my mid length slot, too close to the back of the mag well. Technically my slot isn't too short, it just needs to be moved toward the muzzle by 0.075"
It fit in every lower I tried, so I didn't notice the mistake.

Three options.
1. If yours works and you are happy with it, continue to enjoy it.
2. I can send you a new and fixed device with money to return your defective one, whether you have an issue or not.
3. You can lengthen the slot toward the muzzle end with a dremel tool. 0.075" should be more than enough.
It should still hold well even if you mangle that end of the slot a little. The rest of the slot will hold it. I will have to work out a quick way to fix the remaining devices with my machinist.

It is easier if you send any correspondence to my email address, but you can PM me if you prefer that method. Please include your name and forum handle. It helps me keep things straight.

I have received a few orders today. I will hold onto those until I can get my stock devices corrected.

David Sims
dmsims21@gmail.com
830 Alley Dr.
Friendsville, TN 37737

[dmsims21]

I have the devices back from the machine shop. I had the mag catch slot lengthened. I also had it cut 0.05" deeper in case a mag catch had large lead in chamfers.
I sent one to the customer who had a problem. Once he confirms that the modification worked, I will begin shipping orders again.
Hopefully I can ship on Monday.

[LRRPF52]

I tried the device in the following lowers:

* NoDak Spud partial fence (reproduction of the Colt Model 602, early 603, and 605 rifles/carbine from the early 1960s)

* Palmetto State Armory A2 x 2

* McKay Industries A2

It worked just fine in all of them. This is a great training aid for the AR15/M16/M4, which can be used in conjunction with a chamber flag in a classroom setting.

[explorecaves]

Just had a thought. Using the holes in the bottom portion of the device, could you design a lever that screws on after inserting it into the mag-well with thumb screws that would allow you to use your thumb to reset? In my mind I am envisioning there would be no more movement of the thumb than what it would take to flip the safety on and off. Could even design the adaptor lever to be ambidextrous by making it a 3 piece U-shaped lever held together with screws.

[dmsims21]

Explorecaves, u r right on the money.
I have the holes there for that exact purpose.
I eventually will have something polished enough to sell, but in the meantime, I figured guys could rig up something on their own. My prototype is cut out of wood.
I will post a picture later.

[dmsims21]

I want to clarify my post above. I was trying to encourage new ideas. I appreciate Explorecaves' idea. I want customers to come up with more. One of the things I like about the Dry Fire Device is that it is made of plastic. Customers can round edges, add a chamfer, build up a spot with epoxy, etc.
I added the holes, so all sorts of things could be added on.
1. Wider pad that is more comfortable for your finger.
2. Thumb lever

If you don't like the loud click, you can add some mole skin or felt pad to the spot where the hammer contacts the lever. I wanted the loud click, so you could hear it when doing dry fire practice at the range with earplugs in.

I also figured out a way to work the lever as you lower the rifle from your shoulder.
First, attach a carabiner to the handguard. Then tie a cord to the lever, run it through the carabiner, then tie it to your arm above the elbow. When you lower the rifle from your shoulder, the cord gets pulled, which in turn pulls the lever to recock the hammer. Just start from a low ready, shoulder the rifle, aquire the target, pull the trigger, follow through, then lower the rifle back to a low ready position, and repeat.
This would be good for practicing snap shots like you would take when stalking for wild game.
That is probably more confusing than help. I will put a video on my youtube channel (Friendsville Precision) in a day or two.

Again, thanks for everyone's interest and input.

[dmsims21]

One more thing.

A friend of mine, who is an engineer for a big gun company, ran my spring through a spring life cycle estimation program.
The spring should last for 10 million cycles.

To the first person to wear out the spring: I will send a free replacement spring and a box of moleskin for the blisters.