Steel:Gun vs Knife

[mrkurtz]

I've learned a bit about knife steels, but what do they use in the manufacture of firearms. Certainly the selection of alloy is as important for a blade, but no one talks about it. Any one know?

 

[Confederate]

Well, if you're talking stainless, I wish I knew. Guns have to be made from very high carbon stainless -- but they are very resistant to rust. People have buried them and put water sprinklers over them and left them for a weekend soaking and dug them up days later with no rust. Salt water works much more slowly in rusting a stainless handgun, but once the process starts, it can proceed actually faster than on a regular chromium-moly steel.

Knives are primarily made for hardness and edge retention. Firearms have to take horrendous pressures and resist gas cutting, particularly in the forcing cones of revolvers. Two police officers in Kentucky had Smith & Wesson 686s and the barrels had poor heat treatment. The stainless front sights began wearing down from just holster wear. Barrel wear also was found to be excessive. In the same sense, bad heat treatment and quenching can affect a blade's quality. Unfortunately, you have to trust a knife maker or a gun maker to do it right because I don't know any way to test either except through hard use.

There's also the issue of cast steel or forged steel. People sometimes criticize Ruger for using cast steel, but their guns seem to last a lot longer and be stronger than Colt and Smith, which use forged steel. Still, this is probably more due to the design of the gun. Forged is the best way to go, all things being equal.

Perhaps someone knows what type of stainless firearms makers use. My guess is that they use different types for different parts. They all will rust and corrode if neglected. Many quality knives will stain if exposed to acid and salt, but are pretty resitant to water.

-Confed

 

[Willard P]

The steels used in firearms are softer than what's used in knives.
During the firing process a gun has to endure tremendous amounts of pressure and heat. Recievers flex, barrels will bulge ever so slightly as a bullet travels down it's length. It is torqued and can bend(bbl whip). And endure this for thousands of rounds during it's usefull lifespan

AR15 barrels for example are made of 4140 or 4150 chromemoloy(sp?) or stainles. The recievers are aluminum.

 

[beefangusbeef]

Don't forget S&W titanium and scandium. There are carbon fiber barrels out there too (10/22)! Well not completely, but they're really really light and dissipate heat quickly

 

[fudo]

I had an interest in engraving at one time. During my research, I discovered one source that statedthat most gun steels Rc at about 45.

 

[Gringogunsmith]

Gun parts vary greatly in hardness.
4140 is the norm and hardens evenly throughout due to the molybdenum content.
We used to make sure Mauser and '03 receivers were around 35-40 R.
Bolts should be around 40- 45, sears and hammers and their pins are in the 52-55 range.
If I were building a firearm from scratch I'd use 4340 kept about 35-40 R

The stainless used by most manufacurers is normally 415 and needs a moly lube to keep it from galling.

Rugers stainless frames are all cast and then machine finished.
Rugers stainless is far superior to others.
Bill's master plan was using investment casting...

Here's a site most folks don't know about.
The " other" Ruger
Enjoy. !

http://www.pinetreecastings.com/Casting/index.html

 

[Confederate]

This is all great info. I understand that some of the early attempts to make guns from stainless were disasters, especially in semi-autos.

Sometimes I wonder how important stainless is for knifemaking. Are really good stainless blades better than carbon steel blades (corrosion aside)?

With something the size of a blade, I would think it would be fairly easy to get a good, consistant quality and a uniform hardness. Yet the Chinese are putting out garbage blades I guess to cut corners. But how consistantlly good are the blades from Benchmade, Spyderco, Cold Steel and CRKT? Each one can be off 1-3 levels of Rockwell hardness as I understand it.

Confed

 

[Gringogunsmith]

To my limited knowledge there has never been a " low carbon tool steel" made for cutting other steel.
Carbon content is the key to durable and hard... after all, the earths pressure and time turn carbon into diamond.

IMNSHO The modern stainless is the obvious choice for guns and knives.
Not because it's the best... only the most practical and " good enuffer".

 

[Gringogunsmith]

I expect a toss at cobalt from my reply.
I'll address that later.

 

[beefangusbeef]

I understand that some of the early attempts to make guns from stainless were disasters, especially in semi-autos.

Yeah stainless can be tricky! When the Tikka T3's first came out they had a bad batch of stainless go into some of the 300wsm barrels. Needless to say they found out the hard way. No one was hurt thankfully and they recalled them quickly. That being said I love mine and it's a wonderfully accurate rifle for the money.

 

[Gringogunsmith]

Another was an outfit that created an aftermarket stainless barrel setup for the Ruger 22 auto pistol... ?? started with an " A". ???
Too hard and chipped the extractor cutout into the chamber.. every time.
Pure Junk.

 

[Confederate]

Now that we're completely off thread here, I bought a number of AMT Lightnings years ago when I was a dealer. I kept the only two that worked and when I'd put through about 250 test rounds, cleaned 'em both up and they're still with me in pristine condition. They had better triggers, Millett sights and were all stainless (even the mags).

All the many others I tried would jam every other magazine. Still, people wanted them, and one later got broke in and never had another problem.

AMT had many, many problems with their stainless guns. In many ways, I don't think stainless in knife blades would have come as far as it has without the four or five generations of stainless guns that didn't work.

Confed

 

[gunmike1]

The Smith & Wesson .500 Mag is made of 410 stainless, with a lot of attention to heat treating. It seems to work good, as the .460 Mag runs at rifle pressures, but the guns keep asking for more.

 

[Gringogunsmith]

Now that we're completely off thread here, I bought a number of AMT Lightnings years ago when I was a dealer. I kept the only two that worked and when I'd put through about 250 test rounds, cleaned 'em both up and they're still with me in pristine condition. They had better triggers, Millett sights and were all stainless (even the mags).

All the many others I tried would jam every other magazine. Still, people wanted them, and one later got broke in and never had another problem.

AMT had many, many problems with their stainless guns. In many ways, I don't think stainless in knife blades would have come as far as it has without the four or five generations of stainless guns that didn't work.

Confed

There ya go !
AMT !
Yep.. You cured my alzzzheiniezzz diseaze ! :thumbup:
Hardballer ! Another pice of chit !

 

[fudo]

Gun parts vary greatly in hardness.
4140 is the norm and hardens evenly throughout due to the molybdenum content.
We used to make sure Mauser and '03 receivers were around 35-40 R.
Bolts should be around 40- 45, sears and hammers and their pins are in the 52-55 range.
If I were building a firearm from scratch I'd use 4340 kept about 35-40 R

The stainless used by most manufacurers is normally 415 and needs a moly lube to keep it from galling.

Rugers stainless frames are all cast and then machine finished.
Rugers stainless is far superior to others.
Bill's master plan was using investment casting...

Here's a site most folks don't know about.
The " other" Ruger
Enjoy. !

http://www.pinetreecastings.com/Casting/index.html

Thanks for the link. Lots of things that make you go Hmm.

 

[Phil in Alabama]

Mike Walker from Remington worked with Crucible Steel of NY to develop the type of stainless steels used for gun barrels. IIRC, 416 is the type. I have read that gun makers learned to use different types of stainless steels for different parts of guns, specifically to mitigate that "galling" problem that early stainless guns displayed. Apparently when similiar stainlesses are run together under friction, they gall up, and differing types don't.

 

[Alpha Knife Supply]

Guns have to be made from very high carbon stainless

410 and 416 stainless both have .15% carbon. This is much less than the lowest quality stainless steel blades. For example 420J2 has .26% - .40%.

In many ways, I don't think stainless in knife blades would have come as far as it has without the four or five generations of stainless guns that didn't work.

I disagree. The only connection I know of between low carbon stainless steel used in guns & high carbon stainless steels used in blades is the word "steel". Some knifemakers were forging 440C rod into knives in the 1960's.

 

[Phil in Alabama]

Queen Cutlery was using stainless steel during the 1920's. The first commercial stainless gun barrels that I can recall reading about happened during the 1960's, as a result of Mike Walker's collaboration with Crucible. There might possibly have actually been some before the Walker/Crucible connection, but I cannot find anything in the way of references.

Gun barrel steels are WAAAAYYYY softer than any practical knife blades. I remember reading some here a while back about this, and IIRC, the gun barrel stainless would Rockwell in the mid 40's.

I read some more about the galling of the stainless steels, it has something to do with the erosion of the microfilm of chromium oxides that form on the s urfaces of the metals, leaving them vulnerable. If I could remember where I read that at, I would put the link up. Might have time another night to search it out again.

 

[fudo]

Keep in mind that ordinance steels are not for cutting, they are for containing pressure. Two totally different missions. Just comparing hardness is comparing apples to oranges.

 

[M Wadel]

i remember reading something about stainless steels for guns and similar. they are precipation hardening low carbon, may be wrong tho. its sounds possible since you wont have the same problems with formstability i suppose, they keep their shape after hardening/aging because they need lower temps. does anybody know if this is correct?