HOME MADE RECOIL SPRING TESTER

[RaymondMillbrae]

OK, folks,

Yall have helped me out in the past, so now I guess it’s time for me to give back. (Maybe this will stay a "Sticky").

I was sitting around and looking in my tool box, and I noticed that I had a few recoil springs floating around. Upon checking the notes I had marked them with, I realized that I had not specified the weapons that they came from. (My 10mm, or my .45 ACP).

Shoot!!

So that got me thinking. Hmmm…how do you test for recoil spring poundage?

I started looking online, and realized that those recoil spring testers are either super expensive ($80.00 smacker-roo’s), or almost impossible to find.

So I put ON my thinking cap, looked at a few pictures of professionally-made ones, and said to myself, "Shoot...I can make one myself"!

So here in front of yall, for the whole world to see, is my creation.

Here is a rundown of the parts, and what they cost me:

3/8” x 10” galvanized pipe nipple - $4.53

3/8” cap - $1.47

5/16” x 8” hex cap screw - .37 cents

25 pound fish scale - $9.99

* a few washers that I had laying around

This recoil spring tester only cost me $18.00…and the value of having it is immeasurable!

I got the metal parts at Lowes, and the fish scale at a sporting goods store. (You can go even more "ghetto" and use PVC pipe nipples and caps, and a less expensive fish scale). But I was not comfortable with PVC parts, and I thought a cheaper scale would not be too accurate.

Anyhoo...here is a step-by-step guide – with pictures - to making your own recoil spring tester.

Consider making this a “sticky post”.

Below are the parts I used to make the recoil spring tester. (See inventory list above for details). Make sure to purchase a bolt that is NOT completely threaded.

Below are a few pictures of the new bolt and the pipe nipple. The bolt head will need to be ground-down to fit inside the pipe nipple. Here are a few pictures to show you a before and after of the bolt head and threads. (I didn’t like feeling the threads at the end of the hex screw…so they had to go).

cont'

[RaymondMillbrae]

Cont'

After the bolt head (and threads) are ground down, the next step is to get a few washers and stack them onto the end of the pipe nipple. (In this picture I only show 2 washers, but in the end I had to use 4 of them. More later).

After the washers are stacked on the end of the pipe nipple, get the cap and screw it on very tightly to seat the washers onto the end of the pipe nipple. This is a very important step, as the washers must be flush with the bottom of the pipe nipple. After you have done this step, remove the cap, and you should have the washers imbedded into the cap.

Now we are going to take a very important measurement. This measurement will be taken from the end of the pipe nipple where the cap was removed from. (See…now you will know why it is so important to ensure that the washers in the cap were flush with the end of the pipe nipple). For a 1911 pistol (Government model), the spring must be compressed to a size of 1.625” inches when taking the measurement for the spring poundage. (As per a note I found on the Brownell’s website, and also another pretty good source). And from my understanding, “Wolf Springs” also supports this.

Below is a picture of me measuring the 1.625” compression distance. This is measured from the bottom of the pipe nipple. Then I used a counter sink to mark the spot at EXACTLY 1.625”. (You can see the countersunk spot in the picture). This point will have a small hole drilled into it, so that I can see when the spring is compressed down to this size. More later.

[RaymondMillbrae]

Cont'

Once the 1.625” spot is marked, the drilling begins. Below is a picture of me drilling a tiny pilot hole (to ensure I am in the EXACT SPOT I am supposed to be in), before going to a larger drill bit. There is no specific size hole that you need to drill. Just drill it large enough for you to see the bolt head and spring when it appears there. While I was drilling "the window," I took advantage and also drilled a very small hole on the threaded end of the hex bolt. (My madness for this will be revealed shortly).

By the way, all the drilling was done with a plain ole' Milwaukee cordless drill.

Once these holes are drilled, place the cap, with the washers inside, onto the pipe nipple. Tighten the heck out of the cap! Like I mentioned before, I “initially” only had 2 washers in the cap. But when it was super tightened, the washers rattled around inside the cap – revealing to me that they were NOT FLUSH with the bottom of the pipe nipple. So 2 more washers were added to ensure they were tight (and flush) with the end of the pipe nipple.

Now that the cap is on tight, with the washers flush with the bottom of the pipe nipple, drill a hole in the center of the cap. This hole needs to be large enough to ensure the hex bolt will pass smoothly through the washers and cap.

OK…now we are done. This picture below shows the finished parts.

Cont'

[RaymondMillbrae]

Now lets get down to the nitty-gritty and show you how this “corn-fangled contrapshun” works.

The next 3 pictures show you how to set the recoil spring into the recoil spring tester. First you need to place the spring onto the hex bolt. Be VERY SURE to place the tightly-coiled portion of the recoil spring towards the top of the hex bolt. If you don’t, the other end (the piggy tail) will slip around the bolt head when you are compressing it, and wedge itself between the bolt head and the inner walls of the pipe nipple. Once the spring is placed onto the hex bolt, insert both of them into the pipe nipple in the same way I am showing in the pictures.

Once the parts are in the pipe nipple, you need to place a heavy duty ring into the small hole we drilled onto the threaded portion of the hex bolt. Also take note of the line I engraved into the sides of the “window”. This is the center line of the window, which is EXACTLY 1.625" inches. When the bolt head and spring hit this line, we need to stop and take our reading. (Follow along and all will be made clear, Grasshopper).

cont'

[RaymondMillbrae]

We are done. Now just hook-up the ring to the fish weighing scale…and “Let’s get ready to ruuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuumble”.

This picture shows you how I prefer to hold the recoil spring tester. I find it more comfortable to pin the scale on the ground with my left hand, and then grasp the pipe nipple and pull it with my right hand. Now you can see why it is so important to make sure the washers are flush with the bottom of the pipe nipple - as this is the “0" mark where we begin to measure from. The window is at the 1.625” mark, where we need to compress the spring to. When the top of the spring/bolt head hits the mark on the “window,” the recoil spring is compressed to the specified 1.625” point, and the poundage on the scale is read.

Here is a close-up of the window. Look closely, and you will see the bolt head and spring, lined-up with the line on the "window".

And here is a closer look at the scale, itself. Notice that this paticular spring is an 18-pounder.

It’s that easy, folks.

And for your information, if you have a 1911 commander model, the compression point where you take the reading from is 1.125”.

And if you have a 1911 officer’s model, the compression point where you take the reading from is .700”.

Since I only have a Government model, I only marked the 1.625" point.

And one more point before I conclude: There are various types of fish weighing scales. Some will weigh items from 1 pound all the way to 50 pounds - which is too much. (The larger the scale variance, the less accurate the scale will be). So just purchase a scale that will cover the the recoil spring poundage that you use. In my case, it was 1 to 25 pounds.

Hope this helps someone out.

Thanks again for being a help to me. I was glad to oblige.

In Christ: Raymond

[wide45]

You put a lot of work into that. Thanks for a new way to make a spring tester.

http://www.brianenos.com/forums/index.php?showtopic=3920

http://www.brianenos.com/forums/index.php?showtopic=49888

http://www.brianenos.com/forums/index.php?showtopic=64317

http://www.realguns.com/Commentary/comar16.htm

[RaymondMillbrae]

Thanks.

I had read the first link you posted a while back. And I had also read the last link you posted.

But you know the ole saying, "A picture is worth a thousand words".

So I figured I would do a step-by-step instructional that was simple to follow, with a monitary breakdown of the parts as well.

Hope this helps someone out.

In Christ: Raymond

[Jaxshooter]

Excellent instructions and pictures. If you can't make a spring tester with that info you have no business owning a gun.

Thanks for going to the trouble to share the info.

[vluc]

hmm, anyone know the spring compression for a Glock 34?

[shooterbenedetto]

THANK YOU!!!! time to make one for my 1911 and CZ recoil springs..

I'll make sure that the bolt they slide into are SMALL enough for the CZ and Tanfoglio

as the diameter of the recoil springs are smaller than 1911s..

SB

[RaymondMillbrae]

Shooterbenedetto,

I'm not sure what a CZ spring looks like...but I would have the spring on hand when you go looking for the correct-sized bolt.

Just find the bolt that the spring fits into nicely, with MINIMAL amount of play...and that's the size you need.

You can also mark off different compression distances (Commander, Government, Officers, etc), and drill various holes for them on your pipe nipple.

Or if you have the means, use a milling machine to cut a nice loooooooong oval window in the correct area. Then place lines for the corresponding recoil spring sizes on the sides of the window. (Wa-La...you can now check recoil springs from various weapons)!

In Christ: Raymond

Edited September 27, 2009 by RaymondMillbrae

[Loves2Shoot]

Clever.

Do you mind if I show an easy, cheaper, more versatile way to do one that I haven't seen anyone suggest yet?

[wide45]

Clever.

Do you mind if I show an easy, cheaper, more versatile way to do one that I haven't seen anyone suggest yet?

Please do.

Brian's forums are all about sharing better ways to do things.

[Loves2Shoot]

Well, Raymond went through a lot of effort, so I don't want to detract from the excellent work that he did, but this is stupidly simple with things that most shooters already have.

Parts list

1. El cheapo cleaning rod w/ extra attachment rod or jag.

2. .25" drill bit and 3/32" (or other small) drill bit

3. Tiny split ring (if you want to use a fish type scale, but you can use a regular scale also by pushing instead of pulling.)

Steps

A. Drill a hole in the top of the handle

B. Drill a hole in the extra extension (you can trim down a rod or attachment) and attach the split ring if you want to use a fish scale.

C. Assemble per photo and weigh the spring.

You can measure most all recoil springs with this setup. For recoil springs like in the M7 you could throw washers on it.

Edited September 28, 2009 by Loves2Shoot

[RaymondMillbrae]

Cool idea, LovesToShoot!

I love to see ingenuity at work. Mine was just ONE WAY to skin the cat.

If I may...the end of your rod (opposite the brown handle) will need some washers or something to ensure the spring is totally perpendicular to the rod, as this will provide a constant "zero/starting" point.

Then the compression points for different recoil springs (Gov't, Commander, Officer) will need to be marked on the rod itself.

Once again, great tip.

In Christ: Raymond

Edited September 30, 2009 by RaymondMillbrae

[kimberacp]

raymond, great post with a very detailed photos. I get the idea and will make one.

thanks

[RaymondMillbrae]

raymond, great post with a very detailed photos. I get the idea and will make one.

thanks

Great!

If this thread helps someone, I have achieved my goal - giving back to the shooting community.

In Christ: Raymond

[Josh Biondi]

Well, Raymond went through a lot of effort, so I don't want to detract from the excellent work that he did, but this is stupidly simple with things that most shooters already have.

Parts list

1. El cheapo cleaning rod w/ extra attachment rod or jag.

2. .25" drill bit and 3/32" (or other small) drill bit

3. Tiny split ring (if you want to use a fish type scale, but you can use a regular scale also by pushing instead of pulling.)

Steps

A. Drill a hole in the top of the handle

B. Drill a hole in the extra extension (you can trim down a rod or attachment) and attach the split ring if you want to use a fish scale.

C. Assemble per photo and weigh the spring.

You can measure most all recoil springs with this setup. For recoil springs like in the M7 you could throw washers on it.

Scott... you're great!!!!!!!!

[boz1911]

Pretty sporty, nice job. Looks like I'll be able to figure out what all the loose recoil springs I have laying around are now...

[jmorris]

Very good step by step and photos.

As long as we are sharing, here is a photo the ones I use. It’s just 1X1 thin wall box tubing with one side cut off and the ends folded up. ¼” rod for the spring and a clevis or eye bolt accepts the fishing scale.

[COMATZD]

Ok, so where would one find the proper test lengths for various springs? Does Wolf have this info or something?

[RaymondMillbrae]

COMATOSE

here you go.

RECOIL SPRING COMPRESSION RATES

I went by this website, and I also got some info from 2 other places. (Which I cannot remember, or find, at the moment).

Sorry.

In Christ: Raymond

[openmike]

I built one that measures with a digital scale when the spring is compressed to 1.600. I found a few springs that were obviously mis-packaged.

[dvc4you]

I built one that measures with a digital scale when the spring is compressed to 1.600. I found a few springs that were obviously mis-packaged.

Could you please explain how you did it, I recently bought a postal scale and I am trying to figure the easiest/cheapest way of doing this.

Thanks,

Edited November 2, 2011 by dvc4you

[Jeffrey Yao]

Could you please explain how you did it, I recently bought a postal scale and I am trying to figure the easiest/cheapest way of doing this.

Thanks,

I hope it makes sense. This might be the easiest/cheapest way to test recoil spring.

In Govt model of 1911, 1.625" is the spring length when the slide is in full recoil. I took a guide rod and Sharpie to mark the point where the spring will be compressed to 1.625" as in first picture.

As in 2nd picture, I put a 7lb spring to the guide rod, and on a food scale, I push the plug until it reached the line I marked with my Sharpie. This simulates the spring in full recoil when the slide bottoms out.

The reading on the scale should show the spring weight at full recoil in a Govt model of 1911.