6 springs walk into a bar

Doing some some spring testing over the next few days and I thought I’d see what peoples expectations vs reality is on springs.

All being tested on a j10 acr ( by far my easiest blaster to repeatedly tear down , just stock removal and 3 pins) which is a perfect nylon stock box with green oring and air seals epoxy’d etc.

In the running for top spot is from left to right ,
¹_1.1mm x 165mm from a new spare gen 9 gearbox i bought.
²_1.1mm x 150mm with almost 1 coil less than the next spring , from a gen 8 jinming spare box
³_1.1mm x 150mm with almost 1 coil more than last spring , from the acr’s original gen 9 box
⁴_1.2mm x 140mm from a spare skd ss gen 8
5_ 1.25mm x 140mm with more coils ,from another skd ss gen 8
6_ M90 - already been tested and the obvious winner at 300+ avg fps.

Place your bets on what will achieve the best fps based on whats known.

Edit : finished and here are the results

All are avarages…
Spring1: 250
Spring 2: 230
Spring 3: 250
Spring 4: 250
Spring 5: 210
Spring 6: 300

So nearly 1 coil more ina 1.1mm gives me 20fps more lol. And the same as a 1.1 thats 15mm longer? Weird.

And weird the 1.25 was the worst at 219 fos average


If you cut a bit out of the rear in the main body then it will be 1 pin and out comes the spring retainer.


I seen ppl that left just enough there for a metal washer to screw a shot bolt in to secure the spring guide o.o

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Like this?


I also blew the plastic retainer out with the m150 spring. Lol

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what barrel and nozzle?

Onto it .Im just sussing out exactly what to cut out . That looks a bit more than i was going to take out , leaving the channel i cut out for wire separate but yours is all in 1. Looks good

And i like that washer behind the spring guide.

I only have 2 more springs to test , and so far the results arent whats to be expected…

@Obskewa I used a dremel with the sanding bit. It fitted perfectly

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Yeah cool i got that bit.

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arh i see, you are using the rear of the gear box to secure it O_O
the one i see uses the back of the recerver, he made a cut out there big enough for the spring to come out but still have enough meat around for a washer to secure.

have no idea where i saw it tho = .=

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Finished the tests and results are in the 1st post.

Anyone wanna buy a 1.25 spring haha

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it’s interesting that No.5 “1.2mm x 140mm with more coils” got the lowest FPS out of all of them

looking at it it seems the coil count is as follow.

  1. 1.1mm x 165mm - 250 @ 18 coils
  2. 1.1mm x 150mm - 230 @ 15 coils
  3. 1.1mm x 150mm - 250 @ 16 coils
  4. 1.2mm x 140mm - 250 @ 16 coils
  5. 1.2mm x 140mm - 210 @ 20-21? coils
  6. M90 - 300 @ 30 coils

material? wire thickness? coil gap? length?
just by looking at the result, it’s actually rather confusing as why some spring works better than the other :sweat:

btw, while the average has been shown, did you notice which spring has a more consistance FPS?
or less difference between each shot so to speak :thinking:

PS: i am curious if you spring 1 was cut down to 150mm-ish, or 16 coils
will it perform like spring 2 or spring 3…

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Even weirder spring 5 is 1.25mm!!! I made a typo originally.

Yep it really depends on the soring not numbers. Unless theres an M in front lol.

Actually mostly pretty consistant across the board around 5-10 fps up or down from the average. I restarted the chron every time i recorded a shot as really low or really high messong upnthe averages and did my own averages from them too.

Yeah if #1 was cut would be interesting. I expected it to do more than the other 1.1’s but this whole thing has thrown me.

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some of the chrono results that helped me decide. Ignore the max min and averages for theses photos.