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Suitable Mav/Furyfire spring upgrade?

As it says on the tin. I have a bunch of oldies lying around and I'd quite like to give them a bit more oomph.

The full draw on a Mav/Firestrike spring is about 50mm, since it doesn't compress all the way. With the 4Kg draw =~40N, that gives an approximate spring rate of 8N/mm, which is really rather high compared to most. Obviously it also needs to fit through the ~20mm catch mechanism, and compress into the ~20mm space behind the catch. That's making finding a suitable replacement spring quite a challenge - I don't really want to try to squeeze in an overly long spring, but all the others with a high enough strength to be worthwhile are possibly too wide to fit through the catch mechanism. I've also tried looking at spring stocklists but haven't found anything which fits all the requirements, or which doesn't have a minimum order price.

The closest I've found so far is the BSUK 7Kg Firestrike spring, which is only slightly too long, has what should be a suitable strength boost and doesn't cost a stupid amount, but I'm not sure if it'd actually fit through the catch mech - I suspect it's slightly larger diameter than the stock springs are. Does anyone who happens to have one of these fancy finding out?

Alternatively I could just sacrifice two of them to double up the springs in the other two, but that feels like a dirty way to do it - or perhaps in a tribute to the age of the blasters I would be better off just to do it the really old fashioned way and get out the pennies and hot glue.

NB: Not the Blasterparts springs. With the postage included I don't fancy paying twice what I got each blaster for per spring!

I've got an old Firestrike I'm playing with as an ongoing project.

Don't bother with trying to double spring it by overlaying the springs. It just feels horrible to prime as the springs can't compress nicely without hitting bits of the shell inside, and doesn't always catch the mech properly. (I'm sure ON will be along in mo to curse anyone who ever suggests double springing).

Firing it I've not noticed any increase in range, and tested side by side with a stock FS there doesn't appear to be any gains from double spring (fired at the same time from each hand both darts will hit the door at the end of my hallway at the same time, about 35ft away).

AR removal and some PTFE tape under the o-ring on the plunger head, along with some grease inside the plunger tube have given an airtight seal, as well as an increase in velocity compared to the stock blaster in side by side testing (can't give FPS figures as I don't have a chrono).

I've yet to play with adding a spacer to the back of the plunger head to give full compression to the spring, but that's the next step before upgrading the spring. And then it's on to brassing the barrel for maximum gainz!

Take maverick/furyfire.
Throw as hard as you can towards nearest bin
Enjoy extended range.

If you are working on a firestrike or any direct plunger blaster, putting any tape under the O Ring will cost FPS, it's a floating o ring, it needs to move in the groove to minimise breakaway friction and maximise piston velocity. The big gains in the firestrike/nitefinder are in better barrel fit (17/32 ID brass, about 100-150mm long) and spring rate, basically more is more if the barrel is good.
If you have a poor/damaged O Ring get to a plumbing/car place and find a new one, NOT too big, you want it to move in the piston. Some plunger tubes are also deliberately tapered- calipers can check, so if you have a "perfect seal" at the top 1/3rd you have too tight at the bottom 1/3rd where all the compression and firing power gets made.

Well that's a pretty clear spin on matters Razz I'll just settle for "Functional" and stick to the newer blasters for perfomance

You are fighting against the terrible performance of the reverse plunger system. That's why elite era stuff largely shoots much better out the box, because they ditched reverse plunger for the more efficient and powerful direct plunger layout.

Time to paint them up and leave them somewhere to look pretty then Razz I was aware of the reverse plunger system, I was just hoping that a decent spring would give them the oomph to sit next to stock Elites - but oh well. I'm very unlikely to use them at widegames anyway, I have enough decent armament for that by now

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