I was wanting a way to check recoil springs, as I have several and had no idea if they were 12lb or 21lb, or what.
I know, Brownells has a tool you can buy, but I was not wanting to buy yet another one use tool.
I looked at how they were made and some writeups on home brew versions, and went to my hardware collection.
These are stupid easy to make, the only critical measurement is the "standard length" used to measure spring compression .
What I did was take a piece of 3/8inch ID pipe about 9" long. Then cut a piece off and filed it to 1.625" (the spring must be compressed to a size of 1.625” inches when taking the measurement ) . This is for the Government size, Commander is .5" shorter.
Then put that spacer on a long rod and drop it into the 3/8 pipe. I had a 20" long bolt with threads on just the end. Mark the bolt where it clears the pipe, and file a witness mark there and highlight it with some paint.
Next, drilled a 1/8" hole in the end of the bolt so I could attach a fish scale.
To measure a spring, remove spacer, replace with spring and drop it into the 3/8 pipe. Pull to witness mark and read weight on scale. It helps to have a known spring to practice on so you get the hang of it.
This is accurate enough to tell one spring from another.
One thing this setup does is identify springs that are too long. If your recoil spring coil binds before the "measured length", it will damage your bushing lug and cause accuracy problems as it loosens. I did have one spring that was too long.
I know this may be clear as mud, but will post a pic tomorrow if anyone is interested.
I know, Brownells has a tool you can buy, but I was not wanting to buy yet another one use tool.
I looked at how they were made and some writeups on home brew versions, and went to my hardware collection.
These are stupid easy to make, the only critical measurement is the "standard length" used to measure spring compression .
What I did was take a piece of 3/8inch ID pipe about 9" long. Then cut a piece off and filed it to 1.625" (the spring must be compressed to a size of 1.625” inches when taking the measurement ) . This is for the Government size, Commander is .5" shorter.
Then put that spacer on a long rod and drop it into the 3/8 pipe. I had a 20" long bolt with threads on just the end. Mark the bolt where it clears the pipe, and file a witness mark there and highlight it with some paint.
Next, drilled a 1/8" hole in the end of the bolt so I could attach a fish scale.
To measure a spring, remove spacer, replace with spring and drop it into the 3/8 pipe. Pull to witness mark and read weight on scale. It helps to have a known spring to practice on so you get the hang of it.
This is accurate enough to tell one spring from another.
One thing this setup does is identify springs that are too long. If your recoil spring coil binds before the "measured length", it will damage your bushing lug and cause accuracy problems as it loosens. I did have one spring that was too long.
I know this may be clear as mud, but will post a pic tomorrow if anyone is interested.
