Roller-Delayed Blowback

>>33042717
As elegant and cool as I think it is, it doesn't seem to do anything other designs can't do better. It gets dirtier than gas operated or short recoil guns, has a shorter lifespan, is often less accurate, and recoils harder. I don't see delayed blowback anything ever making a comeback...unless of course the Maxim 9 does better than expected.

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>>33042761
>less accurate

M8...

>>33042779
I messed up on that point, you're right.

>>33042717
I hate diopter drum sights
Everything else about these HK roller delayed guns are fine except the sights and the lack of bolt hold open on last round fired
They are popular, reliable, and there are a ton of magazines and parts available. So new ones for civilians are expensive, used or older or copies will be cheaper.

>>33042717
It works in the guns that have it. No new weapons should use it, though. There's no point.

>>33042761
>recoils harder. I

the MP5 has the least recoil of any 9mm carbine i have ever shot and i've shot about 5 of them

the mp5 is like butter

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>>33044395
>the MP5 has the least recoil of any 9mm carbine i have ever shot and i've shot about 5 of them

I own an HK 94

can confirm, also it's very accurate

Isn't mechanically retarded blowback typically less flexible in the loads it will cycle reliably?

>>33044484

no, it is the opposite

reliability becomes a function of bolt thrust as opposed to ammo dependent gas port pressures.

HK set up the rollers to function with the weakest expected ammo, then the spring loaded buffer helps protect the receiver from battering when shooting stronger ammmo

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>>33044484

my HK 94 does everything from hotloads to subsonic with out an issue

rape

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>>33042779
>>33044395
>>33044427
>>33044527
>>33044537
So then what's the bloody problem with it?

>>33047297
Who said there is a problem with it?

>>33042761
>It gets dirtier than gas operated or short recoil guns

Never figured why that would be...

>>33042717
Yes to all 3.

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>>33047297

there is no problem with it

OP said something about it being for "people too poor to have a proper gas system"

when in actuality the roller delayed blowback costs more to produce than a gas system and is usually only found on high end $2000+ HKs and clones

Go shoot an MP5 or HK 94 and then shoot a gas operated AR15 in 9mm and tell me which is more pleasant

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>>33047371
>usually only found on high end $2000+ HKs and clones

They cost more because they are fringe and obsolete guns that have to be made from scratch by skilled workers. Not because they are good.

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>>33047360
>>It gets dirtier than gas operated or short recoil guns
>Never figured why that would be...

it does not, they have never used one

just noguns memeing

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>>33042761
>It gets dirtier than gas operated or short recoil guns

This is true.

>has a shorter lifespan

So... you have to eventually replace the rollers in addition to the extractor and firing pin?
Because other than that, no, it doesn't.

>is often less accurate
>and recoils harder

Are you even trying now?

Tbqh I prefer gas operated systems for rifle calibers, but roller delayed pistol carbines / SMGs are god tier.

>>33042761
>It gets dirtier than gas operated or short recoil guns
No, it doesn't.

>>33047387
>They cost more because they are fringe and obsolete guns

nope, they were always fairly expensive

the machining to create the bolt on a roller delayed blowback is far more complex than say an AR bolt, you are simply wrong

>>33044537

How did HK get away with such a shitty extractor spring design

I heard those stupid springs only last a few thousand rounds before you start getting FTEs

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Love me some ptr 91.
The recoil is more like a shove, than a kick.
Also, for $900 new, it's moderately accurate with steel cased russian ammo.

Eats coyotes regularly.

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>Post a pic of the MP5, the smoothest least recoiling best SMG ever made
>bitch about it

no

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>>33047408
>How did HK get away with such a shitty extractor spring design

>>33047408
>I heard those stupid springs only last a few thousand rounds before you start getting FTEs


it's probably the most reliable 9mm smg ever made

you are retarded

>>33047408
>How did HK get away with such a shitty extractor spring design

bc HK is Germany's Colt, meaning welfare queens who have a gun monopoly and don't really have to work.

>>33047415

>900 new

Where the hell are you getting yours?

The expected retail price on PTR's website for the barebones railless GI model is $999.

>>33047371
>Go shoot an MP5 or HK 94 and then shoot a gas operated AR15 in 9mm and tell me which is more pleasant

fucking this

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>>33047390
>>33047399

Yes, they do get dirtier. They're about as dirty as direct blowback guns.
It's fairly easy to figure out why.

>bolt starts traveling back immediately after the bullet leaves the casing
vs.
>bolt only starts traveling back after the bullet has cleared the muzzle

It's delayed blowback, but still blowback. The guns have fluted chambers for a reason.

>>33047317
The police forces, militaries, and individuals around the world who use ARs/AKs/etc. instead.

>>33047464
>bolt only starts traveling back after the bullet has cleared the muzzle

you meant to say

>after the bullet has cleared the gas port and the gas travels to the piston?

>>33047488

Piston movement and unlocking takes time. By the time the bolt actually starts traveling, the bullet is long past the muzzle and the pressure is down.

>>33047464
>They're about as dirty as direct blowback guns.

This. Everybody else talking shit otherwise have never owned one before

>>33047464
>They're about as dirty as direct blowback guns.
Every self loading firearm design is about that dirty because chamber blowback is where most of the dirt comes from.

>>33042717

its less mechanically complex than a gas operated rotating bolt action

tl;dr if it aint broke don fix it

>>33047486
ARs and AKs are cheaper with a greater market ecosystem. That's literally it.

>>33047396
>Because other than that, no, it doesn't.
except the receiver stretches until oversized rollers won't adequately headspace the gun correctly.

other than it being shit it's gtg though.
>>33047408
>few thousand rounds before you start getting FTEs
about 2k, recoil spring itself every 1k

>inb4 my pakishit runs fine
yeah on semi...

>>33047543
Long recoil.

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>>33047543

Nigger what

Go compare a PTR 91 after 5k rounds without cleaning to a Scar 17 after 5k rounds without cleaning

You're a delusional noguns faggot

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>>33047580
>about 2k, recoil spring itself every 1k

>>33047591
I'll give you that one, I don't own any shotguns and I can't think of any other small arms that use long recoil.

>>33047602
https://www.youtube.com/watch?v=PApRcRE-ft8

He's lying too.

>>33042717

Neat and simple action but it does have its drawbacks. It runs dirty, but that's to be expected from an action that behaves similarly to direct blowback.

Biggest drawback I think is the life. Roller to receiver tolerances need to be spot on for an accurate/reliable gun. Once they start wearing down you really need to keep an eye on them. And when the receiver wears to the point oversized rollers can't compensate, you're fucked and need a new receiver.

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>>33042717
I dunno bro, mine is pretty fun.

>>33047631
This video is misleading.

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>>33047616
Remington Model 8, a John Browning semi-auto rifle.

>>33047659
>N...no it isn't true
Fuck off fag. My experiences had similar results. It's a fucked up design.

>>33047663
Neat, I always assumed that was short recoil.

>>33042717
>obsolete
Anon, I don't think you understand what that word means. The flintlock is obsolete. A roller delay is pretty much the only concentric way of delaying blowback, though almost no one takes advantage of that.

>>33047689
>A roller delay is pretty much the only concentric way of delaying blowback, though almost no one takes advantage of that.
Nope. you could use just a very heavy spring. ofc, racking the action would be very hard then...

>>33047631

I talked to a LEO guy who said their armorer changed out those extractor springs every time they guns got cleaned, because they were cheap in bulk and known to shit out so often.

>>33047659
How the fuck so? You'd be hard pressed to find any place in the world that puts more rounds through their guns than that

>>33047743

That a problem specific to the MP5, or does it happen to the G3 as well?

>>33047777

Not sure what the G3 bolt looks like, but if it uses the same extractor spring design I'd assume it would.

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>>33047442
Hmm. This would be like winter 2013 on Atlantic firearms. Came with every thing you see, except the cheek riser, sling, glass, and bipod. That bipod was cheaper on hk parts than any where else, even used. And I still paid $120 new.

>>33047743
>How the fuck so?
You can't really determine the cause of the failures they have. It could be something they're doing, it may be the manufacturer of the parts they chose rather than the design. Maybe the video itself isn't misleading, but people read way too much into it.

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>>33047891

I think it's just a heavily beefed up verison of the MP5 bolt.

>>33044395
My buddy has a Zenith MP5 SBR. It has significantly less recoil than my 9mm AR pattern SBR. Blowback guns in general get very dirty but I will say that the system is pretty robust. I have a CETME that only shoots wolf 308. It gets absolutely filthy but is utterly reliable

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>>33047415
That looks very nice, Anon.
>Muh HK91

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>>33047371

>Go shoot an MP5 or HK 94 and then shoot a gas operated AR15 in 9mm and tell me which is more pleasant

Tell me about these gas operated 9mm AR15s. I'm pretty sure there ain't no such animal. all 9mm ARs I've seen are straight blowback.

I'd be curious to see how the recoil feels compared to a similarly weighted eurocuck converted pistol.

>>33047580
>about 2k

Yes, the bronze extractor springs are shit and can last anywhere between 500 and 5000 rounds. They get bent really easily, too.
The simplest upgrade you can make to your MP5 is getting a steel G3 spring. They last much longer, work much better, and don't cause any issues as long as you're using good ammo.

>recoil spring itself every 1k

This, on the other hand, is complete bullshit.
The recoil spring barely settles by 1k rounds, so if the rifle starts malfunctioning by then, you have a different issue, most likely some shit ass underpowered bargain bin 9mm ammo that is causing short strokes or feeding issues.

>>33049288
Nice.

>>33047371
Wasn't the whole point of roller delayed system that it is cheap to make?

>>33049767
That's what I thought too, I think the claim that it's more expensive is BS.

>>33049390
>so if the rifle starts malfunctioning by then
never sad that. it's done to extend receiver life since the design is shit and it batters itself t death even when """functioning."""

>>33049767
the whole point of roller delayed blowback was the German government was completely autistic about barrels being drilled for semi/auto functioning firearms due to fuddlore. that's why so many of the early war and prewar guns used workarounds.

later on it became a cost saving measure in the stg45 prototypes.

>>33047408
>FTE

pro-tip: roller-locked guns will function without an extractor since the case pushes itself into the ejector

I wish PTR would start making 9mm roller-delayed guns. It would make me very erect.

>>33050092
or a 5.56
there aren't many hk33 clones out there

>>33050076

While this is true with straight blowback guns (some you see don't even have an extractor, period), a roller-delayed action cannot extract reliably without an extractor.

Why don't you take a select fire mp5, remove the extractor, and tell us all how well it functions?

>>33049380
There are a handful of em including 7.62x25 and 10mm versions, but those are a rarity

>>33049767
>>33050000
Being a stamped metal gun helps cut costs, eventually, but even without the rollers the G series guns weren't exactly hastily slapped to together tube guns.

>>33050410
>muh select fire

full auto has nothing to do with it

the statement is that roller locked hk's *can* function without an extractor, absolutely nothing was said regarding reliability.

>>33050526
>absolutely nothing was said regarding reliability.
wew.

>>33050541
>can't read

wew

>>33050555
>This car functions great.
>I didn't say it was reliable.
wew.

>>33050583
>great
>if i make a strawman by adding my own words, i win the argument!

wewlad

>>33050526
>absolutely nothing was said regarding reliability

Nigger what

>guy makes claim that HK's ejector spring design on the mp5 is garbage in design and needs to be replaced every 2k rounds
>you argue that the roller locked action will function with or without an extractor
>somebody points out there's no way it will function reliably without an extractor especially in full auto
>muh ***can*** function without an extractor

>>33050526

If you call stovepiping and other FTE failures every 1.05 rounds "functioning" then all the power to you I suppose

>>33050526

I wouldn't call a single shot mp5 a functioning firearm.

>>33050594

>if I drop a random label literally no educated individual would use in real life, I win the argument!

wew laddie

>>33042779
Just because something can be made accurate doesn't mean it normally is. The PSG-1 is prohibitively expensive. Simply put, having a shitload of locking lugs that are actually locked for an extended period of time leads to a case that is supported almost exactly the same way every time. Having a bolt that goes fucking flying backwards almost immediately leads to less intrinsic accuracy.

Remember kids, accuracy is about everything happening the same way every time.

>>33050454
Ignoring the guns themselves, because every HK is autisticly complicated, I'm wondering why a roller delayed system would be more expensive than gas operated. It doesn't make sense to me.

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Less accurate?

My friend. I usually check the rankings of nearby competitions and most people in the Top 10 use this for sports shooting.

It's accurate as fuck, sturdy as fuck and reliable as fuck.

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>>33050845
You should take a look at the rolls Royce of battle rifles.

When it was made, it was the most expensive rifle ever issued to an army.

>>33050900

what is that

>>33050935
That is the Stgw 57 aka SIG 510 battle rifle, chambered in 7.5 Swiss.

>>33050867
>check swiss competitions
>rifle literally subsidized by the swiss government is used by many competitors
Its a poverty rifle.

>>33050978
Clearly you have no idea.

A rifle like this >>33050867
Costs more than a SCAR 17, and it shoots better too.

>>33050900
And every Swiss gun is an expensive meme, not sure what your point is.
>>33050845

>>33050900
Wonder how a HK roller delayed would benefit from a trunnion similar to a STGW (the two removable cups)?

>>33050978
If only it were, I'd have one.

ROLLER STRONK, TIGHTER LOCK UP MORE ACCURATE, MORE CHAMBER PRESSURE, CZ52 CC MASTER RACE.

>>33051217

>tighter lockup

True due to design, as it wears the strength of the lockup is not compromised as the rollers compensate for that. However as it wears, the headspacing does change. It's easy for these guns to slowly creep into dangerous headspace territories at higher round counts if the armorer doesn't keep an eye on them.

>more chamber pressure
This is untrue.

>>33047408

Only valid criticism so far. The HK roller delay guns have a very goofy extractor spring design. It does work so long as the gun is operating normally but a failure that leaves a case or live round where it should not be can pivot the extractor far enough to ruin the spring. I killed 2 extractor springs because I had a bad (cheap korean) magazine spring that was popping live rounds loose while the gun was cycling.

If everything is actually correct they will shoot problem free for a very very long time.

>>33050845
It's not as if gas systems are any more complex. Bit easier to use a metal tube, or a tube and a rod which are pretty straight forward, vs rollers

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>>33042717
>>33047543
>>33047602
>>33042890
>>33042761
>>33042717
>>33042717
>>33042717

your cat is posting again

So is a ptr91 a strait clone of the g3 aside from semi auto or does it just look like one? Also how is parts interchangability with an hk91?

>>33054241
>Hurr I am the all seeing god of 4chan
>>33042761
Is mine not OPs retard

>>33042717
What about durability? Everything I've heard about roller-delayed blowback is that they're much more rugged than most gas systems when it comes to functioning in shitty conditions. Every review says it never fails to feed.

>>33047390
2 1 4 3 5

>>33054329

Basically the PTR-91 GI model is the closest thing you can get to a real G3 you can get nowadays aside from the old HK91's that aren't sold anymore. And even the HK91 didn't have a paddle release like the G3 did, whereas the PTR-91 does.

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>>33054329
The PTR GI is basically a straight semiauto clone except for the cosmetically incorrect cocking tube.

>>33054660
Where did you get that grip? Mine is one piece, navy lower. Fucking hate the grip almost as much as I hate the trigger pull

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>>33055315
Mine came with it since it's the GI model. You can buy the metal lowers from robertrtg and hkparts though.

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>>33055315
Also, how does one go about fixing the trigger pull on the ptr91? I don't feel like paying $100+ for a williamson trigger job, or whatever.
>pic unrelated

>>33042717
no

Hai guys!!!! Am I missing something? https://www.youtube.com/watch?v=WEPwmYcCPFs

>>33042717
>people too poor to have a proper gas system on their weapon
>people who buy HK
are you retarded son

op is a moron

>>33047464
I thought in the G3 the bolt started moving back after the barrel reached a certain safe level of pressure, after the bullet left the barrel. I thought that's part of the reason it was so inherently accurate, no moving parts until the bullet is gone and no gas port.

>>33059122
You are correct.

>>33059122
>>33059150
That's not correct. The bolt starts moving immediately, that's why it's a delayed blowback and doesn't have a locking system.

>>33042717
how the fuck does the shit even work anyway?
goddamn krauts and making shit confusing

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>>33060014
>doesn't have a locking system
>The extra mechanical work that must be done to overcome this force generally allows the pressure in the barrel to fall to a lower level by the time the bolt starts to move backwards and thus delays the motion of the bolt until the bullet has left the barrel and the pressure has already dropped to a lower level.

http://firearmshistory.blogspot.com/2010/08/actions-blowback-action-roller-delayed.html

>>33060028
See above

>>33060014
>The bolt starts moving IMMEDIATELY
> that's why it's a DELAYED blowback
Did you even think before you posted?

>>33060044
>>33060122
If it's not locked it does start moving immediately, it has to. All the delaying does is only allow it to move a very small amount backwards, until the pressure is safe for it to go the rest of the way. If you thought about it before posting you might have figured that out.

>>33050070
I'm fairly sure that the stg45 was the first ever recoil-delayed blowback.

>>33042717
>Is roller-delayed blowback an outdated and obsolete action type that needs to be retired?
Serious answer: they've always been a shitty solution for intermediate calibers and above

leave that non-locking bullshit in pistol calibers

>>33060304
Nigga, where are you getting this not locking idea from? That's what the rollers and locking piece do. Read the article I posted, it's got a lot of detail.

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>>33042717
gas system. nigga please don't tell me you fell for that meme. we all know the germanophiles would be best at gas systems anyways, if you catch my drift.

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>>33047595
Ok

>>33050753
>accuracy is about everything happening the same way every time.
No, that's precision. Accuracy is about hitting your target.

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>>33060122
>>33060044
Not that anon

That animation is bs. There is no physical reason why the bolt should stay in place and wait till the bullet leaves the muzzle. The entire idea of delayed blowback is to make the advantages of simple blowback guns available for high powered ammo.

A simple blowback gun needs a certain mass so that while the bolt moves back when the barrel is still under pressure the movement doesn't go so far as to expose the thinner weaker part of the case which may cause it to rupture. See top picture.

With high powered ammo the mass would become prohibitively high. So the solution the delayed blowback gun offers is to decrease the movement by making use of the law of the lever, i.e. to exchange movement distance for force. It's like a transmission gear. But the movement starts immediately, just like in simple blowback guns. This is why the chamber needs notches. The higher pressures of high powered ammo press the case against the chamber wall which would lead to case rupture due to friction if the notches wouldn't allow gases to act on the outside of the case, too, so that the pressure differential is within limits.

>>33060563
>That's what the rollers and locking piece do.

Wrong. They just slow the movement down so that you don't have to use a 5 lb bolt assembly with 7.62 NATO like you'd have to with direct blowback.
The bolt head is not physically locked into place and starts its rearward movement the moment the case starts exerting pressure on it.

>>33060044

That gif is retarded. It shows the bolt magically gain momentum from nothing - it stays still until the bullet leaves the barrel (meaning the bottom of the case stops exerting any relevant amount of force on the bolt head) and then the whole thing starts moving for no apparent reason whatsoever.

>>33060654

This guy knows what's up.

>>33060563
There is no locking piece you illiterate nigger, that's why it's a blowback

>>33061448
>no locking piece

wat

http://www.hkpro.com/index.php?option=com_content&view=article&id=135:guide-to-hk-locking-pieces

>>33061520
If the rollers were actually locked they would be roller locked guns, not roller delayed blowbacks. Really not a hard concept.

>>33061520
Not that anon but that's just lazy nomenclature. These things are called Steuerstück in German, literally: control piece. Because the angle of the front flanks determines the transmission ratio between bolt head and bolt carrier and thus controls the movement of the bolt assembly.

>>33061568
>not that guy

i personally could not care less about this autistic argument on semantics. saying there is no locking piece is demonstrably wrong, according to manufacturer literature.

and yes the bolt does start moving immediately but the movement is small enough to be considered negligible. get educated, you stupid niggers.

>>33061615
>get educated
Not that anon, but that is something you should take to heart rather than recommending to others.

Conceptually firearms can be classified /wrt
1) bolt position
2) locking system
3) drive mechanism
4) force induction and drive element

Bolt position can be open bolt or closed bolt. Locking system can be locked bolt or unlocked bolt. Drive mechanism can be manually loaded, half automatic or fullly automatic. Force induction can be recoil or gas operated. Drive elements can be gas pistons, gas tubes, with forward motion, backward motion etc etc pp.

Locked in the sense of the locking system of a firearm means a system that is characterized by ensuring absolute rigidity of the bolt until it is safe to open the barrel from behind. I.e. the bolt is blocked or barricaded from movement.
Unlocked means a system without absolute rigidity of the bolt. I.e. the bolt and the case move backwards under a pressured barrel. Of course for reasons of safety this movement has to be retarded/slowed down/delayed so that the case is always sufficiently supported as long as the barrel is under pressure. But because it'S an unlocked systems this has to be ensured by other means than absolute rigidity, namely:
1) the extraction resistance of the case out of the chamber
2) inertia of the bolt mass
3) friction between bolt and receiver
4) tension of springs

That's exactly what happens in a delayed blowback gun. It makes clever use of inertia to delay/slow down/retard the movement. But it DOES move under pressure, the movement starts immediately. The bolt is not blocked from movement. Think about it. There would be no physical reason for the rollers to leave their pockets if it wasn't for the bolt head to push them out. The bolt head moves at once. This is btw the reason for the great accuracy advantage of delayed blowback guns, because the movement follows the gas pressure curve, i.e. there are no distinguished force spikes that affect accuracy negatively.

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>>33061615
Autistic arguments on semantics are my forte, friend. Also,
>>33061891
this.

>>33061891
>i already said the bolt moves immediately
>tells me to think about what i already said

REEEEEEEEEEEEEE

>>33061939
The difference between a locked and unlocked bolt is essential. It's a major design decision that spawns entirely different sets of design problems each. To try to discard it as semantics is to tell the world that you don't understand a thing about the mechanics of firearms.

>>33062002
>you

good thing i have never used the term "roller locked"

>inb4 using the term locking piece implies believing in a locked system

if only i paid more attention in middle school german class to point out shitty technical translators at HK

>>33062023
Everybody can recap the course of the discussion. You're not gonna weasel your way out of that one.

>>33062104
>once an autist enters the thread, only two people can post

this is not now 4chan works

>>33062135
I have better things to do. Good night.

>>33062202

but you are not done stopping some other anonymous person "weasel" their way out of a semantics argument on a sicilian cheese making board

REEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE

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>>33042717

It's kind of a stupid system because in theory it's supposed to make the weapon simper and lighter by eliminating the gas system, but it absolutely doesn't. If you've ever handled a G3 or MP5, you would know they are MASSIVE.

Germans being retarded Muslim-loving faggots as per usual.

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>>33044395
>the MP5 has the least recoil of any 9mm carbine i have ever shot and i've shot about 5 of them

You realize that's only because of it's totally excessive mass right?

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>>33062230
>>33062253
>MP5
>MASSIVE
>excessive mass

I don't think you have handled one for any appreciable amount of time.

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>>33047371
>when in actuality the roller delayed blowback costs more to produce than a gas system and is usually only found on high end $2000+ HKs and clones

This is totally wrong, like fuck, you have IAN NARRATING the history of these weapons to you morons, so you don't even HAVE TO READ ANYTHING, and yet you manage to get it completely wrong.

>>33062322
6-7lbs is excessive

>>33062322

yeah, considering a .223 chambered CAR-15 is smaller and more powerful, I would say the MP5 is a retarded huge gun.

>>33060654

This. Roller-delayed blowback functions identically to a comparable straight blowback action.

The roller mechanism is just so you can use a bolt of a practical mass whereas straight blowback systems would need to be stupidly heavy for more powerful cartridges

>>33062230
Germans being autistic is a great argument in favour of RDB systems. Perhaps they simply screwed up a potentially incredible concept.

>>33062445
4u

>>33042717
>Is roller-delayed blowback an outdated and obsolete action type that needs to be retired?

It's not obsolete, but there are several disadvantages that mean it'll probably just stay in special snowflake territory and not be revisited in future designs.

Namely, it's can be a little too finnicky with ammo types. They run very well when they're properly set up, but different amounts of recoil impulse require different locking pieces. Changes between ammo types or suppressed/unsuppressed, or parts commonality between different barrel lengths are not a strong point of the system and can lead to reliability issues.

This isn't a tremendous problem when a rifle is to be standardized and fire only one specific type of ammunition, but in the modern age most procurement competitions ask for a modular design that has parts commonality between infantry rifles, carbines for vehicle crews, magazine-fed LMGs, suppressed/unsuppressed etc.

Secondly, the rollers are just another point of wear. When compounded with the above issue, it means different needs for different barrel lengths are another aspect technicians or armorers need to be trained to account for when tasked with keeping service weapons running reliably.

I see it as sort of like getting into a relationship with a single mom vs. a woman with no kids. She might be totally fine, but from the outside, it's an added complication that you don't have to deal with by sticking to women without kids.

>>33064336
Can't you just change the buffer spring with different ammo?

What if someone made a roller delayed AR upper? That'd be fantastic. I should do that.

>>33062409
you're conflating cost of manufacture and cost of licensure. A gas system is generally cheaper to make than a roller delayed blowback gun, but the Dutch didn't want to license the FAL to Germany after WWII so they charged a gorillion dollarsa for the license. This made a roller delayed blowback gun- which the Germans were good at- cheaper than the gas driven FAL.

>>33065170
You would change the locking piece which changes when the rollers unlock. The other guy is kinda right but the roller delayed system is really not picky at all. I've shot a mag in my PTR with everything ranging from 200 gr to 110 gr in it with no issue. The biggest issue comes with supression which if you just switch to a number 17 locking piece, you don't need to do anything else. Shorter barrels will require a larger locking piece but that doesn't really come into play unless you're reaching HK51 territory.

>>33062517

No one was talking about the (questionable) viability of SMGs, we were comparing 9mm carbines / SMGs in their own right, and your assertion that the MP5 is "massive" is bullshit.
It's noticeably less clunky than the vast majority of open bolt SMG designs, roughly the same size and weight as any traditional closed bolt SMG, and you aren't getting anything noticeably smaller or lighter until you get into the machine pistol form factor.
Look, I don't even like HK, but even I have to admit the MP5 is a great overall design. It does have its shortcomings (complicated accessorizing, long trigger reset, no LRBHO), but it's far from bulky.
Shit, at work I have an EVO, which is like 5 oz lighter than the MP5 while being considerably fatter, having a worse trigger, worse controls and worse handling.

>>33042717
https://en.wikipedia.org/wiki/Jatimatic
just being better in every way possible. So good.

>>33042779
Fuck. Every single platform can be equally accurate as long as you stuff the damn bullet into the barrel straight, and the barrel is fixed straight, and the bore is good and true.

Fuck. you can make an AK-47 accurate at the 600-1000 yard range as long as you stiffen the entire thing up.

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>>33066294
>every single platform can be equally accurate

>>33066037
Why would shorter barrels require a locking piece?

>>33066391
Because the pressure will change at different times than a normal length barrel. The angle on the locking piece determines when the rollers unlock.

>>33066294
>Fuck. Every single platform can be equally accurate

No

>>33066419
Neat.

>>33065585
It'd probably be pointless and shit, but at least it'd be different.

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What about lever-delayed blowback?

>>33068201
Weaker, and takes up more space.

>>33047297
>airshitmaybe.jpg
>bottom of the mag has the bb pushing gear.
airshitdefinitely.jpg

>>33068272
>Knowing that much about airshit
Git

>>33047644
It's not as simple as an mp38, which works just as well. In ww2 your country was laughed at if your weapon required fluted chambers.

>>33068232
Hmmm but Korobov liked it for his TKB-517 desu ne hmm hmm
Perhapsu it is more egonomigal?

>>33068201
I like the fact that is has very few parts. Makes for a retarded-simple disasembly

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>ha ha I have a reason to post it

Dirty? Yes.
Needs to be retired? No, because it still does its job well, and its job is to pretty much keep kicking through being dirty. Though I'd really like it if it stopped mangling my brass. Can't keep the scope mounted if I want a deflector.

>>33049110
I'm going to split hairs, but the mp5 bolt is a scaled down version of the G3, not the other way around.

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>>33050978
Sure, you can get a shot out Stgw 57 for like 400 Swiss Shekels. But a nice competition model is much more expensive (around 2800 Swiss bucks). And then you have tuned models (pic related), but I have no idea how much they cost.

>>33070138
You can rice out anything.

>>33047644
That's a good point, considering the AR18 and its derivatives don't have anything wearing on the reciever at all, and they seem to be what most modern militaries continue to adopt. I wonder if you could fix that.

>>33047297
Everything that uses it, which is a sparse number to begin with, is too expensive.

That's all.

>>33062322
Different person. I have. It's pretty heavy for what it is. I'm sure the weight is helpful for managing recoil, but the system is just as helpful if not more so.

>>33069376

I've seen the dumbest possible POGs assemble M4 bolts with ease though.

Last ditch bump

>>33073678
bump-delayed blowback?

>>33073678
All has been said, has it not?

>>33066265
>no stock
>sling attaches to disassembly lever
>doesn't fire with the vertical grip folded
The angled bolt is an interesting mechanism but the rest of the gun is a total failure.

>>33078571
There's always more to be thought up and proposed.

>>33050753
The PSG-1 is prohibitively expensive because of scarcity, not because of design.

So forgotten weapons just released a video on the Swiss STG 57, roller delayed blowback rifle. Has some interesting things going on in it. Light recoiling (though the 12 pound weight helps), a ring around the end of the chamber that seals the case when it's fired, delaying extraction, and instead of switching out rollers on it you switch out the recesses they go into.