Found a simple method to measure spring rate

[igolfat8]

I was sorting through some recoil springs and thought some “felt” a different rate than others in the same rate. I needed a way to measure spring rate but couldn’t find an simple method in the search function. So .... I took my pistol cleaning rod (minus the jag) and slid a flat washer on it and then a recoil spring. I placed the spring vertically on my digital postal scale. Then I pressed down on the flat washer to compress the recoil spring on the pistol cleaning rod. I read the weight on the postal scale and darn if it wasn’t pretty close to the rated spring weight. I measured all of the springs I had and most were very close, within a few ounces. A couple were a pound to pound and a half off. At least this gives me a method to compare and measure my recoil springs now. Perhaps this method has been used before by others but if not give it a try.

[coolcw1987]

Thanks for the info i have some unknown springs and would be great if i could label them with a weight.

[Climbhard]

What is the compressed length of a spring for a 5” 1911?

[igolfat8]

6-1/2” free length of a 9# spring, compressed length is 1-7/16”.

[gmantwo]

How do you find/know the compressed length?

[barrysuperhawk]

Uhm, compress it?

 

I suppose you could mic the wire and multiply by coils but that seems like math....lol

[igolfat8]

+1, ^What he said ^

[BlueBulletBeaker]

Oh snap this is a good idea. I'm going to try this over the weekend. I have a ton of unknown springs in my kit.

[Treeclmbr]

Great idea, guess im going to find a postal scale now to try this. Ive often wondered what the actual spring weight is after its had 2-5000 rounds shot, and when they loose there set poundage

[Norther]

On 1/12/2018 at 7:17 AM, Climbhard said:

What is the compressed length of a spring for a 5” 1911?

The length 5” 1911 springs are rated at is 1.625”. Commanders are rated at 1.125”, and Officers at 0.70”. 

[Darthrader18]

Never thought about that. Kudos and I'll be using this in the future for sure. 

[tedahlenius85]

Thank you for this idea. I tried it and it was pretty accurate.

[Zmaniac]

Nice tip!   I'm interested in using this method to measure when I need to replace the recoil spring.  So, can anyone provide data on how much a worn spring is reduced compared to a newer one?  Others from this forum suggested replacing when old spring is 3 coils shorter than the new one.  Just curious.  One way to answer my own question would be with a set of various spring weights and seeing which weight was too low.  

[Banacek]

On 1/9/2018 at 6:35 PM, igolfat8 said:

I was sorting through some recoil springs and thought some “felt” a different rate than others in the same rate. I needed a way to measure spring rate but couldn’t find an simple method in the search function. So .... I took my pistol cleaning rod (minus the jag) and slid a flat washer on it and then a recoil spring. I placed the spring vertically on my digital postal scale. Then I pressed down on the flat washer to compress the recoil spring on the pistol cleaning rod. I read the weight on the postal scale and darn if it wasn’t pretty close to the rated spring weight. I measured all of the springs I had and most were very close, within a few ounces. A couple were a pound to pound and a half off. At least this gives me a method to compare and measure my recoil springs now. Perhaps this method has been used before by others but if not give it a try.

That is brilliant, I am going to check my known ones with a few that I have laying around.

[Youngeyes]

Try this one...

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

[Trinimon]

Nice! Gonna have to give this a try.

[tcazes]

Just an fyi, for anyone with a Dillon press, the large pistol primer tube is the exact od to fit perfectly into a 1911/2011 recoil spring. Makes for real easy measuring and most of us have one laying around probably not in use. Slap on a washer, grab a food scale or postal scale, go to town. 

[GrumpyOne]

7 minutes ago, tcazes said:

Just an fyi, for anyone with a Dillon press, the large pistol primer tube is the exact od to fit perfectly into a 1911/2011 recoil spring. Makes for real easy measuring and most of us have one laying around probably not in use. Slap on a washer, grab a food scale or postal scale, go to town. 

Why do we have to go to town? Can't we measure it at home?

[Steve RA]

Only if old and feeble and can't go to town !     

[tcazes]

lol. its more fun to go to town than just stay at home and be old lazy bones

[NuJudge]

There's also this:  

https://www.ebay.com/itm/142770080129

[tcazes]

6 hours ago, NuJudge said:

There's also this:  

https://www.ebay.com/itm/142770080129

 

That's actually really nice looking

[IHAVEGAS]

On 3/31/2018 at 2:57 PM, Zmaniac said:

Nice tip!   I'm interested in using this method to measure when I need to replace the recoil spring.  

 

Before it breaks.

I never replace recoil springs. Only issue I have ever seen is a broken spring in a compact 9mm. 

[tcazes]

i have found that as my splits start getting worse and worse ill replace the spring and it tightens things back up (open gun). usually happens every 4k or so rounds. realistically i could get probably 8 or 10k out of it but they are super cheap so i swap them out regularly. more of a precautionary swap than anything. 

[gigamortis]

I use a 5/8" deep wall socket without any gun disassembly. Place the socket square drive side down on your scale. Place your pistol muzzle over the top of the socket and press down just shy of bottoming out your slide travel. Your barrel will simply extend into the deep wall socket unhindered. Observe your scale reading.