recoil in aeg?

Stercus Accidit

Insane idea here....


If you plopped a lump of lead inside your piston, youd get some felt recoil wouldn't you....

Ok rof would drop, as would fps, due to having a greater mass to accelerate, but balancing it with a stronger spring and higher voltage or higher torque motor could yield results.


Anyone with some free time want to try this?


Ok, possible negatives;

will put much more strain on 1 gearbox, 2 gears, 3 piston, 4 motor, 5 battery, 6 contacts and wiring.

The gearbox on an m4 etc. is a type 2, notorious for breaking under piston impact.


Anyone want to take the plunge? I might try this myself on an old type 3 GB I have.

Bernie Mac

well there should be no space in your piston to fit a piece of lead because all the air is compressed and released out into the barrel.

and if there wasnt it would do some serious damage having a lump of lead in the piston! :P

Stercus Accidit

lol,

no, not in the cylinder, in the piston itself, the bit that moves forward and back.

I think its been done before.

Feck, maybe I'll do an AK with recoil and moving bolt over the college break.

Masada

I cant see it working out to be honest, theres too much involved to make it semi reliable and that before even mentioning the fact that it would be negative recoil, ie, its going the wrong way.

If it did recoil it would be more of a kick away from you instead of back into your shoulder. the reason being that the piston is drawn back a relatively slow speed and released, compared with the forward speed and impact under spring pressure..

I designed and half built a recoil system last year but i never got around to finishing it.
it uses a very basic cylinder with a metal weight in it, an electro magnet on the shoulder end and elastic material on the other to return the weight to the front. it worked really well actually, i might see about finishing that during the weekend.,:)

Stercus Accidit

You'll have a weight moving back and forth, even if it rattles like hell I'd be happy, I understand what you mean about it being in the wrong direction, but in a 10rps aeg, that piston moves back and forth 10 times a second, thats fast, and in either direction you will feel something.

I'm going to give it a shot all the same, your system sounds very cool, I look forward to hearing about it.

The irish seem to be very milsim and realism obsessed altogether!

Masada

Oh i would agree with ya, any movement would make it more fun. I just don't see the Physics of it working out very well,

most average clones would have about 10-12 rps as standard, then adding the weight to that would in theory cut a lot of them off so then you have to spend a load on getting a really high torque and ROF setup. then with the inertia from forward movement you might be looking at possibly shearing the front end of the gearbox off.,

I agree about the Irish though, we seem to be more geared to realism even with the comparatively small size of our community with other countries .,

Stercus Accidit

I think it will work tbh, but you're right, I'll be using a type 3 box (no shearing) and a stronger spring and a large type battery, more current.

If a wa m4 makes such a rattle just going back and forth, an aeg (though with a slower back stroke) should, could do something interesting. Net forces of the mass moving forward and back will cancel each other out, they will be equal, but one will be slower than the other, its just a matter of how much of an effect that will have.

Its all pie in the sky for now, but I'll be having a whack at it all the same.

Would'nt it be epic if it was this simple to get wa m4 gbb performance?

I cant stop grinning at the idea, no matter how likely or un-likely it is to work!


Bye bye gearbox!

Masada

The key is in the way the piston comes back though, when its released forward it travels under spring pressure, the length of the cylinder and then stops dead in the bottom with a bang. this is where you will get the kick.
but when it comes to the piston coming pack, its already going to want to go forward since its under spring pressure, so there is no inertia involved in carrying it back and creating recoil. The piston never actually travels all the way back into the gear box ya see. aswell as the speed difference between coming back and going forward.

This is where we see the difference between the design and theWA blowback, the WA will fire back under very little sprung resistance and it will impact on the end of its travel, therefore carrying more energy through the gun and creating the feeling of recoil.

I know ya mentioned it being a V3 gearbox but i would say there is still a high likelyhood it will shear the front off. V3s arn't immune to it, just better able to resist it. Then you get a weighted piston in there and the weight, higher spring power etc all combine to give you a much high rate of wear on the gearbox which obviously isnt designed for that.

If you had the space, maybe in a box mag or something, what you could do is construct a kinda pendulum with alternating electromagnets on each end of its travel. this would be doable by getting 2 relays, 1 "normally on" and the other "normally off". these would be wired to the one power source so when they are powered up they will change roles giving you the release and attach mechanism on the pendulum. a small positional switch could be inserted in the gearbox that would simply give and take away power to the relays.





Th beauty of this resign is the recoil will be in timing with the firing of the gun and wont really effect the rate of fire.,:)

Stercus Accidit

The spring will only affect the speed of the mass, going forward will be faster than going backward.

If the aeg is pushing a mass forward and back, whether by spring on forward stroke, or by motor on back stroke, by pushing that mass, the aeg is pushed back by it. - newtons 3rd law

So your motor and spring are the same thing here, just one is faster than the other.

There is a sharper resetting of the forces at impact, as you say, this may be the "felt" recoil, than at say the other end, max spring compression, which will be gradual and maybe not felt.

Only way to know how it "feels" will be to do it, and if I wreck the gearbox, it will be in the name of milsim. But, its worth doing, maybe a buffer material of some sort at the end of the piston will reduce the impact on the gearbox body.


TBH your system sounds beyond the sort of thing I'll be trying, I wont have electro magnets and all that! My idea is pretty simple, and as I don't really have access to better things, an added mass to the piston is as far as I'll be taking it for now.

Masada

Post back on how it goes., it'll be an interesting experiment. I might have a aul piston lying around on my desk and theres probably some V3 shells in the freebies box.,:)

Single Malt

I don't think adding mass to the piston would be a very efficient way of generating recoil. Granted, when the spring is released Newton's 3rd law says that a force will be applied to the AEG and your shoulder. But when the piston comes to a stop, all that extra forward momentum will also be transferred to the AEG. This will cause a pendulum rocking motion, and feel quite unnatural, especially considering the forward momentum will be greater than the backstroke momentum (momentum is mass*velocity). It will give a feeling as if something is pulling the AEG away from you when you are expecting it to be pushed into you. Thats all not mentioning the negative effects on reliability and piston cycling due to the greater mass and spring force. I am sure this idea has been researched to death by some of the AEG manufacturers, as an AEG with recoil would be quite desireable for a lot of people.

If it were possible to use a longer piston cylinder coupled with a stronger spring and a negative braking spring, then the forward momentum transfer may be reduced enough to give a decent recoil feel. The spring would absorb some omentum, and help in piston cycling. Still unlikely to work though, and figuring out the springs and cylinder size for firing at 1J would be pretty tough too, due to factoring deceleration.

disclaimer: I don't know a massive amount on AEG's, due to being new to airsoft, but I have several semesters of statics and dynamics behind me.:)

Stercus Accidit

I hear ye, I considered a buffer at the forward most point of travel, but feck it, its too complicated, this in theory could be very simple.

No aeg "recoil" is recoil, it is just vibrating the gun, if it shakes my iron sights and shoulder when I'm aiming, it will be worth it.

A regular aeg just feels so static when you fire, a very clinical whirr and neat stream of bbs.


The philipinos did something like this on a stubby m4, saw it on the philipino forum, oldish post but looked like the same idea.

Masada

A lot of people over rate what recoil is though, the only gun's I've ever fired with a good whack from it are a 12gauge double barrel and an old boltie i dont even know the name of. assault rifles dont have much in the way of recoil compared to boltie's. they have a return spring that soaks up a lot of it.

I was talkin to Tony the other week about the Western Arms blowback compared to the real steel M16A1 and the difference in recoil from the 2 isn't really noticeable.

Stercus Accidit

The WA has a great shake off it, I also used KD's gas mp5 once too.

Its the feedback really I'd like to replicate, pull the trigger and it feels more substancial than a regular aeg.


It might be noisy too

Single Malt

Masada, recoil on full auto is quite considerable. In Cambodia you can shoot all manner of assault rifles, and an AK has quite a kick:). Even on single shot the recoil is enough to have re-align sights when aiming at a 11/2 foot wide target at 50ish metres. I think you underestimate what recoil is:)

Masada

Single Malt wrote: »

I think you underestimate what recoil is:)

I knows exactly what recoil is..,:)

I spent a whole day playing with a whole mannor of weapons unavailable in Ireland on this range last week, and believe me, the "kick" is over rated.

https://www.youtube.com/watch?v=xPmELzAKrHQ

Single Malt

Which was your favourite?

edit: don't answer that. didn't want to hijack the thread:)

Masada

M16A1.,:)

Single Malt

I dunno, m60...feel like rambo. enough now thread derailed enough

TheDoc

Masada wrote: »

I knows exactly what recoil is..,:)

I spent a whole day playing with a whole mannor of weapons unavailable in Ireland on this range last week, and believe me, the "kick" is over rated.

https://www.youtube.com/watch?v=xPmELzAKrHQ

I know this is all good vibe and its not nasty

But that was possibly the best comeback to " well what would you know about it"



Its a very interesting idea alright, I dont know jack **** about it, but get it work, I'll just pass you moneyz

Masada

Anyway., to get this thread back on topic.,


Sam, what are you thinkin as far as springs are concerned? are you gonna use a shorter but thicker coil spring to compensate for the spring space taken up inside the piston?

I might give it a bash tomorrow evening and post a vid or something. ive a few gearboxes lying around doing nothing much.

Maybe even, you could post up a diagram on how you'd like it to be built, others can do the same and we can see if collectively we can come up with a decent idea thats fairly simple and cost effective to make.,

Stercus Accidit

Masada wrote: »

Anyway., to get this thread back on topic.,


Sam, what are you thinkin as far as springs are concerned? are you gonna use a shorter but thicker coil spring to compensate for the spring space taken up inside the piston?

I might give it a bash tomorrow evening and post a vid or something. ive a few gearboxes lying around doing nothing much.

Maybe even, you could post up a diagram on how you'd like it to be built, others can do the same and we can see if collectively we can come up with a decent idea thats fairly simple and cost effective to make.,

I was thinking of avoiding shortening spring travel, by having a long thin weight in the spring, like a spring guide the wrong way round, and cut down the actual spring guide itself(I've skirmished guns without spring guides entirely).

A lump of lead I could shape and fix in place would be ideal, maybe screwed in place by a longer bolt into the piston head.

Stercus Accidit

[DM]-TheDOC- wrote: »

I know this is all good vibe and its not nasty

But that was possibly the best comeback to " well what would you know about it"



Its a very interesting idea alright, I dont know jack **** about it, but get it work, I'll just pass you moneyz

My fuggin idea!


Also yeah, epic responce