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Fang
Jul 9, 2001
If you don't think ponderous, clumsy sentence structure loaded with hamfisted thesaurus wankery makes good writing, you're probably just too dumb to read my posts.

/r/iamverysmart

Cyrano4747 posted:

I don't know as much about how pistols wear as rifles, but on rifles at least throat and muzzle erosion start to impact accuracy long, long before the wear on the rifling is bad enough to be noticeable to the naked eye.

That doesn't happen nearly as much when you're not dealing with high-pressure bottlenecked rounds. 1911s will generally keep good accuracy until the rifling wears down (provided the barrel doesn't shoot loose, of course). I don't know if this continues to apply when dealing with higher-pressure rounds like 9mm or .40 S&W, but I bet it does.

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Militant Lesbian
Oct 3, 2002


Uncle Caveman posted:

Man, every Glock I've ever seen has had some seriously worn rifling. :v:

I got this even if nobody else did.

infrared35
Jan 12, 2005

border patrol qt


Plaster Town Cop

HotCanadianChick posted:

I got this even if nobody else did.

HKs, too. :v:

Elmer Keith used to say that you could expect about a 5,000 round life from a pistol barrel if you were shooting jacketed ammo. Obviously things have improved a bit since the 1940s.

Ygolonac
Nov 26, 2007

pre:
*************
CLUTCH  NIXON
*************

The Hero We Need


infrared35 posted:

HKs, too. :v:

Elmer Keith used to say that you could expect about a 5,000 round life from a pistol barrel if you were shooting jacketed ammo. Obviously things have improved a bit since the 1940s.

Or if you're not running redline-max on every shot...

Fang
Jul 9, 2001
If you don't think ponderous, clumsy sentence structure loaded with hamfisted thesaurus wankery makes good writing, you're probably just too dumb to read my posts.

/r/iamverysmart

infrared35 posted:

HKs, too. :v:

Elmer Keith used to say that you could expect about a 5,000 round life from a pistol barrel if you were shooting jacketed ammo. Obviously things have improved a bit since the 1940s.

Metallurgy has improved a lot. Usually, when people talk about the "superiority of modern firearms :smug:," they don't know what they're talking about; however, when it comes to the things we can do with metal now, modern techniques have definitely surpassed what came before.

That's why I have to roll my eyes when crusty old types get huffy about only settling for forged USGI surplus parts. Sure, it's forged--but it's a forging from fifty years ago. It's not guaranteed to be categorically superior to a modern cast equivalent.

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



Fang posted:

Metallurgy has improved a lot. Usually, when people talk about the "superiority of modern firearms :smug:," they don't know what they're talking about; however, when it comes to the things we can do with metal now, modern techniques have definitely surpassed what came before.

That's why I have to roll my eyes when crusty old types get huffy about only settling for forged USGI surplus parts. Sure, it's forged--but it's a forging from fifty years ago. It's not guaranteed to be categorically superior to a modern cast equivalent.

How do you notice barrel steel behaving?

I'm wondering because I've seen a TON of shot out barrels on 40s era surplus pistols. You really notice it on the German stuff that just had the poo poo shot out of it for decades, especially the Lugers (although I think that's mostly due to people using insane loadings due to pervasive myths about needing an equivalent to +P+ to cycle them reliably), although I've also seen my own fair share of 1911s with heavy wear.

Meanwhile I've also seen people's range 1911s that they claim 20,000+ round counts on that have barrels that, at least to the naked eye, look perfectly fine.

Is the issue just the insane round counts that some of those 60 year old pistols have on them, or is the new steel really that much more wear resistant? I figured given your 1911 obsession expertise you probably have a somewhat unique view on this.

Enderby
Dec 30, 2004



Cyrano4747 posted:

Cheap ammo is my guess.

While I lament the destruction of a perfectly good MAS49 to create that, I can at least see the thought process that went into it, at least initially. Now, I do take issue with some of the design aspects. If you read the description it's described as having an "AR10/AR15" gas system, which I"m taking to mean direct impingement. That's a terrible idea with a gun designed, presumably, to use surplus 8mm Mauser. I"m also a little curious how they modified the FN49 bolt to work as a DI. The FN49 bolt also isn't the simplest. It's not crazy-complicated, but it would still be a bitch to clean up for corrosive in a DI environment every time you fired it.

Dude, MAS49/56. It uses a direct impingement gas system. An FN49 converted to DI would be atrocious on almost every level.

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



E-Rock posted:

Dude, MAS49/56. It uses a direct impingement gas system. An FN49 converted to DI would be atrocious on almost every level.

Hah, you're right. My bad. My brain just kind of took a vacation there for a while.

Fang
Jul 9, 2001
If you don't think ponderous, clumsy sentence structure loaded with hamfisted thesaurus wankery makes good writing, you're probably just too dumb to read my posts.

/r/iamverysmart

Cyrano4747 posted:

How do you notice barrel steel behaving?

I'm wondering because I've seen a TON of shot out barrels on 40s era surplus pistols. You really notice it on the German stuff that just had the poo poo shot out of it for decades, especially the Lugers (although I think that's mostly due to people using insane loadings due to pervasive myths about needing an equivalent to +P+ to cycle them reliably), although I've also seen my own fair share of 1911s with heavy wear.

Meanwhile I've also seen people's range 1911s that they claim 20,000+ round counts on that have barrels that, at least to the naked eye, look perfectly fine.

Is the issue just the insane round counts that some of those 60 year old pistols have on them, or is the new steel really that much more wear resistant? I figured given your 1911 obsession expertise you probably have a somewhat unique view on this.

The steel is very much better than it used to be. 1911 barrels used to be matched with the slide by hand-fitting them to the point that at least one lug engaged to full depth, then firing a proof round. The pressure of the proof round would smoosh the metal in the lugs until all three lugs engaged, at which point it would be strong enough to suffer no further deformation. Nowadays, factory drop-in barrels usually only have partial engagement on a single lug, and they handle thousands of rounds without deformation.

Quality of heat treatment may also be a factor: We can control that a lot better now due to better measurement and heating mechanisms, which allows us to make metal harder without as much risk of brittleness or burning the metal. Better tools might help, too, by permitting more precise bore dimensions and crisper edges on the rifling.

Obviously, there's variation in steel strength quality between modern barrels. I once reamed and scraped the barrel ramp on both a $200 Kart match barrel and a cheap no-name barrel in short succession, one right after the other and the difference in hardness was palpable.

walrusman
Aug 4, 2006



Fang posted:

The steel is very much better than it used to be. 1911 barrels used to be matched with the slide by hand-fitting them to the point that at least one lug engaged to full depth, then firing a proof round. The pressure of the proof round would smoosh the metal in the lugs until all three lugs engaged, at which point it would be strong enough to suffer no further deformation.

Oh my god, that is amazing and terrifying. Part of the proofing process actually involved causing plastic deformation of the barrel?

Gewehr 43
Aug 25, 2003


I love this guy:

quote:



You are bidding on a G43/K43 rifle. [snip]

Additional Information:
Reference Number is JCJ49
We price at the lowest possible price. We will NOT consider any offers lower than our stated price. We will NOT answer email about this subject. It is just as easy for us to block you as it is reply to your message.

That's some customer service right there. :jerkbag:

http://www.gunbroker.com/Auction/ViewItem.aspx?Item=165304369

Pitch
Jun 16, 2005

しらんけど


That receiver seems pretty rough-finished. Late-war expedient or rough life for that particular gun?

Motronic
Nov 6, 2009





Grimey Drawer

walrusman posted:

Oh my god, that is amazing and terrifying. Part of the proofing process actually involved causing plastic deformation of the barrel?

Well....it sounds bad when you say it like that. Part of the proofing process was designed to cause plastic deformation to a couple of engagement lugs that were specifically designed to deform in a manner that causes secure engagement. This isn't all that uncommon today in lots of mechanical fitting procedures (non gun related).

Fang
Jul 9, 2001
If you don't think ponderous, clumsy sentence structure loaded with hamfisted thesaurus wankery makes good writing, you're probably just too dumb to read my posts.

/r/iamverysmart

Motronic posted:

Well....it sounds bad when you say it like that. Part of the proofing process was designed to cause plastic deformation to a couple of engagement lugs that were specifically designed to deform in a manner that causes secure engagement. This isn't all that uncommon today in lots of mechanical fitting procedures (non gun related).

What's also cool is that the 1911 slide bows upward under pressure, with the front and rear end both tipping down about the point of the breech face. This is why the most common point for the slide to crack is at the rear of the ejection port. I was talking to Dan Coonan at SHOT a couple years back and he mentioned that one of the problems he had to solve with his 1911-style .357 autoloaders was binding of the slide at the start of recoil due to how much it was flexing.

Gewehr 43
Aug 25, 2003


Pitch posted:

That receiver seems pretty rough-finished. Late-war expedient or rough life for that particular gun?

No, that's actually par for the course. Incidentally though, thanks for unknowingly touching on an inside joke between Cyrano and I. :)

Anyway, there are 3 types of G43 receivers. Rough forged (like that one), cosmetically machined, and "panel cut."

The first is the most common and from day one they looked like the one in that auction. Some were a little better, some were a little worse, but they were all rough like that. The second type showed up primarily on Gustloff-made guns and a few concentration camp (Neuengamme) Walthers. Those were generally believed to be leftover Gustloff receivers salvaged after the RAF took an aerial tour of their factory at Buchenwald. The last is a slight variation of the rough forged variety. They only show up in a few distinct serial blocks and are essentially rough with a smooth-milled panel that facilitates markings.

Rough forged very early 1944 Walther gun:


Cosmetically machined Gustloff:


Panel cut late '44 Walther:

Pitch
Jun 16, 2005

しらんけど


Gewehr 43 posted:

Incidentally though, thanks for unknowingly touching on an inside joke between Cyrano and I. :)
:ohdear:

I can see how it would make sense to leave them with the natural forged finish. It just doesn't seem... German. :hitler:

Sixgun Strumpet
Feb 16, 2009

Heh, yeah, 'round here I call myself The Enabler. I suspect pretty much everyone wishes they could be me -- I'm kind of a big deal, you see.


Gewehr 43 posted:

Some of us just don't get anything from shooting AR's. :(

Shooting an AR actively creeps me out.

Something about that buffer spring going "Twang" right by my ear. I don't quite know why it bugs me so much.

Roundboy
Oct 21, 2008


ChlorineTrifluoride posted:

Shooting an AR actively creeps me out.

Something about that buffer spring going "Twang" right by my ear. I don't quite know why it bugs me so much.

lube it a bit. i also noticed the more recoil compensation you have, the more noticable it is

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



Gewehr 43 posted:

No, that's actually par for the course. Incidentally though, thanks for unknowingly touching on an inside joke between Cyrano and I. :)

Anyway, there are 3 types of G43 receivers. Rough forged (like that one), cosmetically machined, and "panel cut."

The first is the most common and from day one they looked like the one in that auction. Some were a little better, some were a little worse, but they were all rough like that. The second type showed up primarily on Gustloff-made guns and a few concentration camp (Neuengamme) Walthers. Those were generally believed to be leftover Gustloff receivers salvaged after the RAF took an aerial tour of their factory at Buchenwald. The last is a slight variation of the rough forged variety. They only show up in a few distinct serial blocks and are essentially rough with a smooth-milled panel that facilitates markings.

Rough forged very early 1944 Walther gun:


Cosmetically machined Gustloff:


Panel cut late '44 Walther:


The cosmetically machined Gustloff receivers weren't actually made there, but were produced under contract at St. Etienne in occupied France.


Roundboy posted:

lube it a bit. i also noticed the more recoil compensation you have, the more noticable it is

Don't do this. Lubing that tube can lead to a really gummy mess.

Gewehr 43
Aug 25, 2003


Cyrano4747 posted:

The cosmetically machined Gustloff receivers weren't actually made there, but were produced under contract at St. Etienne in occupied France.

Who ya talking to here, bud? ;) Notice I said "showed up primarily on Gustloff-made guns..."

Anyway, you're exactly right. They were made and machined in France and the vast majority of them ended up in the Gustloff Werke plant inside KZ Buchenwald - though some probably went to Walther's main Zella Mehlis plant too. After the RAF flattened the Buchenwald joint, the leftovers were sent to Walther and probably assembled in their Neuengamme plant.

"Pitch posted:

I can see how it would make sense to leave them with the natural forged finish. It just doesn't seem... German. :hitler:

There was some period discussion on that I believe. They ultimately decided that the cosmetic machining took too long and they needed all the guns they could get. Likewise, the rough receiver holds protective oil better and reduces glaring. Remember it was about this same time that the cosmetic (not functional) quality of all German small arms started to take a huge nose dive. Until late '43, they'd been introducing new manufacturing techniques (stamping parts rather than milling them) and reducing the number of serialized/marked parts to increase production output. In 1944 is when you really start to see the finish and machinework take a turn for the worse. G43 production didn't really start in earnest until early 1944... just as the poo poo was really starting to hit the fan on the homefront.

Gewehr 43 fucked around with this message at 19:25 on Apr 16, 2010

Roundboy
Oct 21, 2008


Cyrano4747 posted:

The cosmetically machined Gustloff receivers weren't actually made there, but were produced under contract at St. Etienne in occupied France.


Don't do this. Lubing that tube can lead to a really gummy mess.

a spritz of clp? I agree, don't grease the crap out of it, but metal + metal contact is always nice to have a bit of slide to it.

spankmeister
Jun 15, 2008








Haha, that K/G43 receiver looks like it's made from cast iron or something.

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



spankmeister posted:

Haha, that K/G43 receiver looks like it's made from cast iron or something.

Welcome to an unfinished forging. All forged guns look like that before they mill the surface to be all pretty.

This is an M14 forging. Garand forgings look quite similar:



I can't find a picture of an AR forging right now, but imagine the same sort of thing: a blob of very rough looking aluminum in the rough shape of an AR lower receiver but fatter in every dimension, since they need to machine the surfaces to fit.

walrusman
Aug 4, 2006



Scroll down to the bottom here. I can't save the picture so I can't rehost; lame.

The King of Swag
Nov 10, 2005

To escape the closure,
is to become the God of Swag.

walrusman posted:

Scroll down to the bottom here. I can't save the picture so I can't rehost; lame.

Here you go:

Pitch
Jun 16, 2005

しらんけど


Cyrano4747 posted:

I can't find a picture of an AR forging right now, but imagine the same sort of thing: a blob of very rough looking aluminum in the rough shape of an AR lower receiver but fatter in every dimension, since they need to machine the surfaces to fit.
AR forgings are actually pretty nice, I assume because of the aluminum. The only cosmetic machining they get is fiddly little stuff like smoothing the mold flash and some companies don't even do that since the thick anodizing will hide it pretty well.

The Bananana
May 21, 2008

This is a metaphor, a Christian allegory. The fact that I have to explain to you that Jesus is the Warthog, and the Banana is drepanocytosis is just embarrassing for you.





Check this out:

http://www.gunbroker.com/Auction/ViewItem.aspx?Item=165572696

quote:

Caution: this does not mean that you can use your 1911 pistol to safely fire a cartridge other than that for it is designed by simply switching magazines - don't try this - it is dangerous!

Faerunner
Dec 31, 2007


It's in no way incorrect, and unfortunately not necessarily unnecessary to add that in.

DAVE!!!(c)(tm)
Feb 22, 2003


The King of Swag posted:

Here you go:


Someone really should cast lower-shaped candy bars. They'd probably sell really well at the candy and jerky booth at gunshows.

Detective Thompson
Nov 9, 2007

Sammy Davis Jr. Jr. is also in repose.

I wonder how much a full sized M16A1 made out of chocolate would go for? Also, how many would one have to eat until they die? Also, it should be full of peanut butter.

Roundboy
Oct 21, 2008


DAVE!!!(c)(tm) posted:

Someone really should cast lower-shaped candy bars. They'd probably sell really well at the candy and jerky booth at gunshows.

its 50/50 that the ATF would raid you for making it able to take standard uppers and go FA

add a serial to it for giggles. Or, make an 80% chocolate lower that people can take to 100% by eating the extra material

walrusman
Aug 4, 2006



I would no-joke pay around $100 for a dimensionally-correct AR15 model made of chocolate. Like with all the moving parts and everything. The bolt lugs would probably be pretty fragile though...

DAVE!!!(c)(tm)
Feb 22, 2003


Then I would have to cast toffee bullets in dark chocolate cases. Every box of 30 would include a marzipan P-mag.

walrusman
Aug 4, 2006



With the judicious use of steel bushings, I bet you could make a 95% chocolate lower function, at least for a few shots.

Rodrigo Diaz
Apr 16, 2007

Knights who are at the wars eat their bread in sorrow;
their ease is weariness and sweat;
they have one good day after many bad

walrusman posted:

With the judicious use of steel bushings, I bet you could make a 95% chocolate lower function, at least for a few shots.

Including the springs? How?

Pitch
Jun 16, 2005

しらんけど


But your hands would be such a mess.

The King of Swag
Nov 10, 2005

To escape the closure,
is to become the God of Swag.

walrusman posted:

With the judicious use of steel bushings, I bet you could make a 95% chocolate lower function, at least for a few shots.

There was a guy a while back who machined a working PTFE (Teflon) AR lower. As I recall, he actually put quite a few mags through it without any failures. This is the same guy who also built an AR lower out of wood (pine?), but had serious problems with the thin walls around the mounting points/lugs cracking and splitting. I don't recall if he ever actually fired it, but I remember him saying that if you reinforced those spots, he had no doubts it would actually work (something to do with the wood actually being extremely strong to the forces exerted during firing, but too weak when it came to the thin areas where the lower would actually mount to the other parts of the rifle.

Pitch
Jun 16, 2005

しらんけど


The King of Swag posted:

There was a guy a while back who machined a working PTFE (Teflon) AR lower.
It was HDPE, made from a plastic kitchen cutting board. And it functioned, but he complained of pretty regular jams because the plastic flexed when firing and caused the buffer tube to go out of alignment.

The King of Swag
Nov 10, 2005

To escape the closure,
is to become the God of Swag.

Pitch posted:

It was HDPE, made from a plastic kitchen cutting board. And it functioned, but he complained of pretty regular jams because the plastic flexed when firing and caused the buffer tube to go out of alignment.

Ah; I knew someone else would remember that guy! I remembered it as him making it from PTFE but HDPE sounds more likely.

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Inspector_666
Oct 7, 2003

benny with the good hair


The King of Swag posted:

Ah; I knew someone else would remember that guy! I remembered it as him making it from PTFE but HDPE sounds more likely.

Yeah I remember the photos. he pretty much just stacked a bunch of cutting boards on top of each other, then hit them with a heat gun until it was a solid block.

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