View Full Version : Stock-removal method of shaping parts

December 22, 2001, 09:59 PM
When a parts company makes a gun part (let's say a slide stop) by milling it from a piece of tool steel, removing all the metal that shouldn't be there until a slide stop is left, what happens to all the metal that was removed? Can it be melted back, with other scrap, into a new tool steel block later on, or is it second-rate after that?

December 22, 2001, 11:50 PM
Don't know bout other plants but one I worked for just put all the ferrous cuttings in one set of drums and all the aluminum scrap in nuther set of drums. They were picked up periodicly by scrap buyers. The ferrous drums had everything from 1010 mild steel to 4340 ordnance grade stuff....along with coolant, lubricant and other junk. No attempt to recycle by specific alloy.

Our Milspec parts were made from certified stock. No way to certify remelt stuff.


John Lawson
December 23, 2001, 12:31 PM
Not to nit pick, but that's ORDNANCE; an ordinance is a law.
Stock removal has always been called "machining". Most of the scrap is sent to Japan, where they add a certain (small) amount of scrap to every batch of new steel. If you have ever tried to machine plates of Jap steel, you get the idea they are getting even for WW-II. It has two very hard surfaces with a softer interior. You can go through lots of milling cutters and drills working with this stuff. Apparently, not much or any steel is made in the US now. Another blow struck by the globalists to punish us for winning WW-II and our subsequent humane treatment of the losers. But, then, no good deed ever goes unpunished.

December 23, 2001, 01:52 PM
Good eye John.:)


December 23, 2001, 04:01 PM
I guess I'd have to take issue with a couple of notions here expressed. One, that the US is a second rate steel producer. In fact, the US and red China typically alternate 1st and 2nd place in total production based on the fluctuations in domestic and international demand. The overall top producer is the European Union, but broken down to its individual countries, no EU member even touches the US in steel production. Japan lags behind all three.

Two, that sophisticated metallurgy is exclusive domain of the US. Some japanese steels are excellent - their swords could cut through american machine gun barrels in WW2 - and Italsider, an Italian steelmaker, was the only bidder to meet NASA specs for some particular subassembly on the Hubble telescope, I think...

So while there is plenty US steel to go around, it doesn't have to be american to be of excellent quality.

December 23, 2001, 06:00 PM
Japan puts out VG-10, which is arguably the best stainless steel used in knives today. (Bladeforums members, please note that I said "arguably.") They also make ATS-34.

John Lawson
December 23, 2001, 07:46 PM
(Retch) I'd take exception to some of those old wive's tales. No katana blade could possibly cut through a machine gun barrel. The rifled liner is carbide. While the Katana is a decent blade, it is no match for a chisel when cutting through steel. If you really believe this tale, let's see you duplicate the feat with a hand held Japanese Army WW-II issue sword. The katana was designed to slice through flesh, not chisel through steel. Even a san mai tanto will not cut through a mg barrel. If you want to prove otherwise I have a WW-II issue new mg barrel you can ruin your Katana on.
If you read the fine print on tool steel wrappers, you will find that the steel ground stock available from machine shop suppliers is made in Sheffield or Stockholm. And, we are speaking of annealed tool steels like SAE 01 here. Only Starrett sells tool steel with no country of origin designation.
While American steel mills turn out sophisticated products, most of them are not tool steels. I'd like it to be otherwise, but if you look at the production numbers from the last few months, you will see a marked dip. Much of this is due to a slowing market in Aerospace and Automobiles.

December 23, 2001, 09:15 PM
Okay, John, I believe you. That makes me wrong on one of the particulars. But the statement that I challenged was "...not much or any steel is made in the US now..." (Your previous post) That statement is patently false. The other was your insinuation that "jap" steel is substandard. That too is false, and an anachronistic vestige of WW2 animosities. The Japanese are now our allies, and their steel is first class.


James K
December 23, 2001, 11:02 PM
The term "stock removal" is used mainly in knife making to distinguish blades ground from flat steel from those made by forging by smiths like Bill Moran.

The more common term in gun work is "machining " or "milling" from stock. This is a bit of a misnomer since in the gun industry all metal parts except those made by metal injection molding (MIM) require some "machining". Both cast and forged parts must be finish machined, though the former requires very little and the latter quite a bit.

This makes it possible for companies to advertise truthfully that their parts are "machined" even if they are actually cast. If the buyer wants to think "machined" means the part is machined from stock or from a forging and is stronger than a cast part, that is his concern.

There are other manufacturing tricks. For example, the frames of the small S&W .22 semi-auto pistols are made from aluminum extruded to the proper shape and then sliced off just as one would slice bread. The "slices" are then machined to the finished shape.


December 27, 2001, 01:01 AM
some companies do recycle by type of steel. Larger operations, usually, with auto-feed machines.

Confirming the rest: Jap swords are no better than anyone else's. Fact. Nowayinhell will they cut through an MG barrel. Hell, they bend on treebranches.

Yes, Jap steel is first class. If you had hard surfaces and softer interior, that was either hot-rolled steel with a skin on it, or an air-hardening steel that had been surface treated.

Most mills add scrap in. It's cheap, it's partially refined already, and it helps stabilize the structure.

Once put back into smelt, the steel is completely recycled. All (for practical purposes) impurities are burned out, then new alloying agents (impurities to the pure iron) are added back in in controlled amounts.