why the gas?

>>30777187
Because the M4 is supposed to be an automatic weapon and the ROF on an "inertia driven" (piston driven a la Benelli ARGO) M4 would be slow as fuck.

Plenty of guns are... "inertia driven". Look at the HK33 or the FAMAS.

>>30777187
because they already have an inertia driven firearm?

File: U9YasJK.jpg (654KB, 1440x2560px) Image search: [Google]

654KB, 1440x2560px

Gas allows low power shells to chamber more reliably than inertia.

>>30777203
So you're saying Benelli M1s and M2s have a slow ROF

>>30777203
This I did not know, always bought into the advertising without looking into it.

>>30777269
This is also a good point. I've never shot an m4 but there's no discernible speed difference between the super black eagle and gas operated shotguns I've fired.

File: inertia action.jpg (33KB, 400x337px) Image search: [Google]

33KB, 400x337px

>>30777203

>Look at the HK33 or the FAMAS.

Those are delayed blowback.

Inertia driven action is different. They fire from a locked bolt, with a bolt carrier sprung against the bolt with a short, stiff spring. When fired, the bolt of an inertia system gun stays locked, and as the gun recoils, the inertia of the bolt carrier causes it to lag behind the rest of the gun, compressing the spring between it and the bolt. Then, the spring pushes the bolt carrier backwards, and when it passes the neutral position, it unlocks the bolt via a cam, and then the action cycles.

A delayed blowback action like the FAMAS or CETME just uses some kind of mechanical linkage to provide a mechanical disadvantage to the bolt, so the bolt carrier's effective mass is increased, making a blowback action for a more powerful round not retardedly heavy.

>>30777211
And it is still shit. Why didn't they just keep to the semi/pump combo like the m3?

>>30778476
Weight and balance IIRC.

We don't replace our M3's because we need to be able to use beanbag and pepper rounds.
M4 won't cycle them well. But is better balanced and less complicated.

>>30777211

Really? I have a gas operated shotgun (mossberg 930), and while i've never had problems, the model is notorious for poor reliability with low powered shells.

>>30778476
good luck finding an benelli M3 convertible.

You can sometimes find it on gunbroker. But all retailers have discontinued the gun

>>30777187
Because M4s can have different stocks, forends, optics, lights, grips, ammo saddles etc mounted.

Drastically changing the weight of an inertia gun can affect the rate of fire/time it takes to cycle. Or it can plain make it not cycle.

>>30778476

Because it is extra weight and complexity and sometimes it makes for two very shitty actions instead of one really good one?

File: image.jpg (51KB, 1047x768px) Image search: [Google]

51KB, 1047x768px

>>30777187
Google: Benelli MR1

This already exists

When I lived in Eurotrashia I owned the shorty version for apartment defense.

>>30778579

There's really not much difference between the two. All that really needs to happen is to disengage the gas piston, assuming the pump handle is normally acting as a non-reciprocating charging handle.

>>30778638
>>30778579
>>30778476
Actually it could be done on really any shotgun not gas operated that is also semi auto.

From the pictures I found, the M3 is closely related to the Stoeger M3000 inertia system

Using the recoil of the shot, the bolt carrier basically pulls a piston back, that "pumps" the tube like a pump action does, pulling a shell back, and into the chamber after the spent shell has been ejected. Carrier moves forward and everything returns to status quo.

If you were to have a pump action added to this, you'd essentially have to basically stop inertia from throwing the carrier back by triggering a lock that keeps it in place like how a regular pump works.

Why is it not really done anymore?

Because it makes the shotgun absurdly complex, almost needlessly so. This also ends up making it delicate.

>>30778610
Where you lived? How you moved?
Anon with a similar story here, I wanna do the same you did.

>>30777203
Are you fucking retarded?

Inertia guns aren't slow in the least, neither of the guns you listed are inertia driven, non of them are slow and the only two valid answers to the questions are

1) it works fine
2) it wouldn't be the m4 anymore

>>30778476
Since you know so much about the systems why don't you tell us?

>>30778579
You're using the internet RIGHT NOW and you didn't bother to look it up. The M3 is not the SPAS and the M3 is simple as fuck. That's like saying making an AR straight pull adds complexity

>>30779444

the M3000 is a copy of the Benelli M2.

https://www.youtube.com/watch?v=4IOvu_eq6uY

>>30778544

this.

>>30781102

it's kinda a crappy pump action, though. i own a 1301, but dad's got a M3 somewhere.

I have an M2 and if I'm shooting sporting clays and accidentally give it the sloppy shoulder it fails to eject. Gas system takes away that possibility for more reliable use.

9 rounds in under 2 seconds isn't slow at all.
https://youtu.be/bVxKnH-VALE

Also, the M4 is not automatic. It is semi auto.

>>30784470
op said "like other" semi-autos

>tried a couple inertia shotguns
>none of them cycled
>slugs barely cycled, stoppages because action wasn't cycling enough

Shit just doesn't run when you're decent at controlling recoil.

>>30785078
Son, you've got this backwards.
Inertia shotguns need a good stiff brace - if you let the whole gun move, it won't cycle.
That is not "decent at controlling recoil", that is "shooting incorrectly".

>>30786822
Actually you've got it wrong, if you brace an inertia shotgun too much it will cycle too slowly. An inertia action needs to move backwards fast enough to get the bolt carrier group moving so that when the rest of the gun stops moving against the shoulder, the bolt carrier group has the speed to cycle.

If you're controlling recoil well, it won't cycle.