Increased Spring Tension on the Mag Release - PS90

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iFire
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Increased Spring Tension on the Mag Release - PS90

Post by iFire » 18 Mar 2011, 18:55

So here is an idea I had to modify the spring pressure on the mag release for the PS90 - I added a second piece of spring to the original to increase the tension on the mag on my first go around. This increased tension helped to eliviate the mag from popping up with some of the bullet/powder/charge combos that i shoot.

It worked so well that I decided to step it up a notch to gain even more spring force and go to a solid, one piece spring.

It is a pain to try and get the spring put in, and takes a lot of patience, but it is well worth the modification. If I were to do this mod repeatedly It would make sense to create a tool/jig to help install the spring...

Sometimes I grow out a small beard... When i have the beard and shoot the ps90 with the original mag spring, I feel the hair in my beard get caught/pulled in the mag realease while shooting... This tells me that it is moving during the shot, so that is why I thought about the mod. With the new heavy spring, I have not felt anything as the mag doesnt even flinch and function has improved. I would never go back to the original spring.

First set-up attempt just to give this idea a whirl
Image

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New Spring - This is a really heavy duty spring, I would say nearly twice the force as the original...

Image

Comparison of the srings - I had an identical spring to the heavy one in this pic that i used and clipped off the amount shown here

Image
Last edited by iFire on 21 Mar 2011, 10:44, edited 2 times in total.

freelienr
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Re: Increased Spring Tension on the Mag Release - PS90

Post by freelienr » 18 Mar 2011, 20:42

would probably be easier to just buy a longer spring?
Great idea though, i've had my mag pop once or twice. Going to have to pull that apart and do this mod!

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iFire
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Re: Increased Spring Tension on the Mag Release - PS90

Post by iFire » 18 Mar 2011, 21:48

freelienr wrote:would probably be easier to just buy a longer spring?
Great idea though, i've had my mag pop once or twice. Going to have to pull that apart and do this mod!
Yup a longer, solid one-piece spring is in my future...

This was just the preliminary experiment to see if it would improve/alleviate the problem...

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Re: Increased Spring Tension on the Mag Release - PS90

Post by panzermk2 » 18 Mar 2011, 22:47

I have to put in an order for a new batch of mag springs, first batch of FsN HD recoil springs. Let me know how it works I may have a run made of HD.
Jay Wolf
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freelienr
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Re: Increased Spring Tension on the Mag Release - PS90

Post by freelienr » 19 Mar 2011, 10:44

what is the new overall uncompressed length of the spring?

freelienr
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Re: Increased Spring Tension on the Mag Release - PS90

Post by freelienr » 19 Mar 2011, 10:46

panzermk2 wrote:I have to put in an order for a new batch of mag springs, first batch of FsN HD recoil springs. Let me know how it works I may have a run made of HD.
You can get FsN HD in the new length?

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Re: Increased Spring Tension on the Mag Release - PS90

Post by panzermk2 » 19 Mar 2011, 22:41

new length? I am talking about a higher rated recoil spring for the FsN.
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iFire
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Re: Increased Spring Tension on the Mag Release - PS90

Post by iFire » 20 Mar 2011, 11:52

panzermk2 wrote:I have to put in an order for a new batch of mag springs, first batch of FsN HD recoil springs. Let me know how it works I may have a run made of HD.
I will try and get out this week and shoot it with a variety of loads, from Standard to Max and see how it handles the different range loads. I will rip it apart and figure out the exact length spring that it can handle. I know when I put my spring section in I was about two coils under the max compressed length that it would be able to accept without bottoming out and no longer releasing the mag. I will caliper my total length, free length between coils, compressed length and wire diameter and shoot you a pm...

freelienr
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Re: Increased Spring Tension on the Mag Release - PS90

Post by freelienr » 20 Mar 2011, 13:56

panzermk2 wrote:new length? I am talking about a higher rated recoil spring for the FsN.
so a stiffer spring to remedy the issue instead of a longer one?

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Re: Increased Spring Tension on the Mag Release - PS90

Post by PainKillaX » 20 Mar 2011, 13:59

freelienr wrote:
panzermk2 wrote:new length? I am talking about a higher rated recoil spring for the FsN.
so a stiffer spring to remedy the issue instead of a longer one?
Won't changing the recoil spring in the FsN change the timing and blowback characteristics? And if so will you have to re-invent all your loads?

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Re: Increased Spring Tension on the Mag Release - PS90

Post by panzermk2 » 20 Mar 2011, 16:53

No because it will have to work with factory loads still.

Think of it as swapping the factory 18 pound 1911 recoil spring with a 20 pound.

Just a little more spring that is all. It will hold the chamber closed for a millisecond or so longer and reduce the amount of shoulder movement though.
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Re: Increased Spring Tension on the Mag Release - PS90

Post by iFire » 21 Mar 2011, 10:21

Added new pics of a solid, heavier, one piece spring...

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