870 Magazine Spring Advice Please

[Tom E Gun]

Background:
I recently purchased a used 870 Wingmaster on the EE. It is missing the magazine spring. I have a spring from SJ Hardware that is intended for a 7 shot magazine.

Question:
Is it OK to cut this long SJ spring to fit my standard mag tube (no extension)?
If so, what length should I cut it to?

Answer:...


Thanks!

 

[manbearpig]

yes you can cut it.
as for the length, noone can give you an exact length since it depends on the particular spring you have - if youre sure its an S&J maybe they can give you a better idea.
insert it as is, test function, snip off a few loops, test function, continue snipping a couple loops at a time.

worst case you can just order an 870P magazine spring from Brownells, its only $4.

 

[Tom E Gun]

Thanks manbearpig, I will give that a try.

 

[hawkrider]

.

 

[Tom E Gun]

Mission accomplished!
It turned out to me remarkably easy to figure out the proper spring length. I just used a little math. I had a spring designed for a 7 round magazine that was 28 1/2" long. I wanted to cut it for a 4 round magazine. So I just went 4/7 x 28.5" then added 3/4" just in case. It worked first try. However I did learn the hard way that you must position the cut end of the spring towards the follower and not towards the spring retention insert. A little blood was spilled when the cut end of the spring started to corkscrew its way through the hole in the retention clip!
Anyway thanks for the input.