Adjustable spring guide

[dt00th]

Has anyone had any experience with or made an adjustable spring guide

 

 

I ask because with more CQB sites opening and lower/stricter Fps it ma be the

 

answer to not having to run more than one gun if you swap between woodland

 

and urban site .

 

 

 

i did do a search so apoligize if i missed an aready topic

 

 

[Yuri]

An interesting idea. It seems to me though that there isn't a lot of room for adjustment since it all needs to fit inside the piston. Perhaps you could do a test where you put shims on the spring guide and see how much difference you see in the fps. But then again, how many shims can you put on until the coils of the spring hit each other?

[counterassasin]

I think on weapons such as the M4, could have a longer spring guide inside the buffer tube. That way, you could slide the stock off, then get access to spring guide.

[dt00th]

Maybe the guide extension could be shorten to allow more adjustment .

 

 

[Docv400]

I've often thought about doing something like that, but always came up with the same answer; I really don't need the ability to change fps in any particular AEG.

If you're stuck with just one AEG, and regularly flit between two (or more) sites with different fps limits, then it might be worth it.

 

Closest I've come is modifying the M249's spring retainer/guide so it has two positions, giving two FPS levels.

Changing the setting is simply a case of hinging the stock open, and pushing the guide in to the second setting (to go from 'high' to 'low'), or releasing the guide latch and letting it move back to the rear setting ('high' to 'low').

[dt00th]

How much movement do you have and how much change in fps does provide

[Docv400]

Ooops, just noticed I put ('high' to 'low') the first time, that should be vice-versa obviously

 

This is one of the ones I've done...

FPS depends on the spacing of the extra groove from the first, but I aim for 350 and 330 ish from the two settings.

The rear groove is the original.

 

It would be possible to have more positions, by machining several 'short' slots i.e. not full circumference grooves, but several partial ones at different positions.

I can't really imagine a need for more than the two (or maybe three max) settings though to be honest.

I think you could get 3 full grooves in, if you made them narrower, and reshaped the retainer latch accordingly.

You could then have a lower than 330 setting, say 280-300 for CQB use.

[dt00th]

Its been awhile since i looked inside a gearbox but i need to get one opened and measure how adjustment space there is

.

if we can get a 20 to 30 fps change i think that would cover most applications .

[ED-SKaR]

Even without the multiple positions, you can use the hole to easly remove the spring and replace it with another one.

 

Added benefit is you can remove the spring before you dissasemble the rest of the gearbox, making gearboxes much easyer to work on.

[dt00th]

star gearbox already has that abilty and there are a couple of aftermarket gearboxes do as well .

 

I have 2 star M4's but the rear of the body is different, the stock tube unscrews to allow access to the spring guide .

 

My problem is since both of my star recievers are now broken and most aftermarket bodies don't have a screw-in tube. The whole lower part of the gun needs to striped down is access tthe spring guide .

 

which is why i was looking into this idea .

[ED-SKaR]

star gearbox already has that abilty and there are a couple of aftermarket gearboxes do as well .

 

 

As does the ICS SA80 gearbox. It has a spring guide with three positions(20-30FPS difference between them) and you can remove it altogether to swap the spring.

[magic_golem]

my star g36 gearbox has a removable spring guide as well, so handy for testing out springs

[LordElpus]

ACM has a complete 8mm V2 gearbox with a hot swap spring. For £50 plus postage, it might be a easier way forward if you have a V2 gearboxed gun

[Vice]

Don't the stock tubes on armalites usually bolt into the back of the gearbox, where this adjustable thing would be..

[Rob15]

Don't the stock tubes on armalites usually bolt into the back of the gearbox, where this adjustable thing would be..

Yes, G3s and MP5s also have a spacer which bolts into the spring guide of a V2 gearbox as well.

[dt00th]

Yes, G3s and MP5s also have a spacer which bolts into the spring guide of a V2 gearbox as well.

 

not sure about g3 neverhad one apart and mp5 is dependent on stock type i think

 

 

It would be easier to remove the stock tube screw use a long alley key to adjust the fps then replace once fps is reached, than disassemble

whole gun /gearbox to change spring no!!.

 

plus the stock tube screw could act like a lock

[dt00th]

Rigth i've had my star apart and i have about 9mm of travel on the piston guide before the spring guide interfers with the piston head bearing

 

 

once i put it back together i 'll start testing how much difference this makes to the fps

 

 

[Vice]

not sure about g3 neverhad one apart and mp5 is dependent on stock type i think

 

 

It would be easier to remove the stock tube screw use a long alley key to adjust the fps then replace once fps is reached, than disassemble

whole gun /gearbox to change spring no!!.

 

plus the stock tube screw could act like a lock

 

 

You'd need to get spacers for the stock screw then, if you had the system fully back (for lower fps) the stockscrew would not go as deep as if you were running a higher fps setup.