casting vs forging of frames and receivers


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kidcoltoutlaw
May 4, 2004, 12:28 AM
is forging that much better than casting and why,thanks,keith

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stans
May 4, 2004, 06:45 AM
Depends on the intended use of the part. A cast 1911 extractor is weaker than a forged (bar stock) unit. Cast metal tends to be hard and slightly brittle, so if the part flexes, like an extractor, it will break. Cast receivers seem to hold up very well, almost as long as forged. The downside is there is more porosity in a casting, so it is harder to get a highly polished finish. But, a very well made casting is durable and can look good. Just look at any Ruger as they use castings for their receivers. Caspian actually has more returns on their barstock receivers than their cast 1911 receivers.

Clemson
May 4, 2004, 09:17 AM
It is not a direct comparison, but most pro golfers (and a bunch of low-handicap amateurs) prefer to play forged clubs vs cast clubs. My game doesn't know the difference, but a good golfer can tell. Several years ago I took the factory tour of S&W at Springfield, Massachusettes. Guess what I saw coming off one of the forging presses? You got it -- club heads being contract-forged for a club manufacturer.

Clemson:p

Jim K
May 5, 2004, 11:00 PM
First, a rant. M1911 internal extractors should be neither cast nor made from bar stock. The extractor is a spring and if it is going to work for any length of time, it must be made out of the best spring steel. Period. End of rant.

As to the cast vs. forged issue. Forging compresses the steel fibers so that for a given thickness of a given steel, a forged part is about twice as strong as a cast part. That being said, in many applications, quality casting can give perfectly satisfactory performance. This is the case with the 1911, since it was over designed in the first place, so even half the strength is adequate.

But if you want a visual lesson, compare the top strap of a Ruger revolver (cast) to the top strap of a S&W revolver (forged) for the same caliber. The top strap takes a lot of strain, and believe me, there is a reason the Ruger strap is thicker.

The problem today is not necessarily one of the manufacturing technique. It is one of using the appropriate technique for the application. For example, plastic has generally worked all right for mainspring housings and triggers. I don't think I would want a pistol with a barrel made out of it.

Jim

stans
May 6, 2004, 06:30 AM
Absolutely Jim! So many manufacturers are using MIM and castings for just about every small part in a 1911. Now we are seeing broken extractors, ejectors, slide stops, thumb safeties, grip safeties, and none of this is necessary. Unfortunately, enough of us want cheap 1911's and the only way to make a 1911 on the cheap is to use the least expensive parts. That means castings and MIM.

A well made cast steel receiver seems to work well, almost as well as forged. You cannot get nearly as nice of a polish and blueing out of a casting and swaging and peening the slide rails on a casting can risk cracking the receiver. A cast slide? There are tons of them out there, some work, some crack in short order.

As for the extractor, I'll take bar stock over cast or MIM, but I agree, spring steel is what John Moses Browning used in his design and that is what works best for internal extractors. Kimber, S&W, Dan Wesson all went to external extractors. Are they better? No, unless you plan to use MIM or cast extractors to cut costs.

1911Tuner
May 14, 2004, 07:55 AM
Howdy guys,

Just to stick my nickel's worth in...

I've heard it said many times that a forged frame or slide is less likely
to crack than a cast frame or slide...and that's true enough up to a
point. The thing that many people don't realize is that cracks usually
start at sharp, unradiused or filleted corners, and in that...a forged slide
or frame has'em too because the grain structure is interrupted wherever
a machining cut is made.

A hammer-forged part is better in this respect in that the shape is hammered out, and the grain structure is preserved as the steel is
literally beaten into shape...but there is still a certain amount of finish machining needed to produce the part.

The main advantage of the forged part is that, if and when a crack does start, it progresses more slowly on a forged part than on a cast part...
and will usually go just so far and stop. A similar crack in a cast part moves quickly and generally breaks through to the air. A crack in a forged part can be check-drilled...and tigged if so desired...and the part will be
as good as new. Check-drilling a cast part mostly just delays the inevitable.

I have a couple of old GI frames that I built up as range beaters that cracked at the junction of the dust cover and frame rails ( that I check-drilled many thousands of rounds ago)...and they've been rockin' and rollin'
without a problem ever since.

Another Auto Ordnance cast frame that cracked in the same area and check-drilled didn't last much longer than about 5 or 6 thousand rounds before the crack started on the other side of the holes. Another 500 rounds, and the dust cover was ready to fall off.

A forged GI slide started a small crack at the ejection port. A check-drill and a touch with a tig welder kept it in service for several thousand rounds. The salvaged slide off the above mentioned Auto Ordnance
pistol was fine one minute...and was broken clear through to the rail
two magazines later...and was cracked in exactly the same spot as the forged slide. The pistol kept functioning...but it started hitting about 2
feet left of center at 15 yards. I thought I was losin' my freakin' mind!

A good investment casting can be very good. I've got a pistol that I built
on a late-production Essex frame and slide that has taken a lickin' and kept on tickin'...but I know that when the end comes, it will come suddenly and completely.

Cheers all!

Tuner

Sean Smith
May 15, 2004, 04:43 PM
Saying cast vs. forged vs. barstock is way too vague. Who cast it? What was the alloy? The heat treat? Is the process highly controlled, or a bunch of yahoos subcontracted out of the third world?

Gary Smith at Caspian's comments on the cast vs. barstock frames they sell:

We get NO (none,nada,zero) returns on cast frames for structual failures. We have had 1 barstock frame come back with a stress fracture near the dustcover.

*I like the cast because I believe they are a good value and allow for more options.
*I like the barstock because they have a nice surface finish.
*The rail dimensions and hole specs. are identical.
*Both have forever guarrantees against breaking.

I don't want to go into the technical aspects, but my opinion is that the cast frame is the way to go. We don't like returns, cast frames don't come back... BUT, not all cast frames are created equal. We use Ruger's Pine Tree foundry for our blanks and pay a premium.
If you intend to put a high polish on your frame then you might want to go for the barstock.
Rail and hole specs and locations are identical.

Something to consider.

stans
May 16, 2004, 11:53 AM
I would not hesitate to use a Caspian cast frame. For a highly polished, especially blued finish, bar stock would give a better finish. Essex cast frame? The newer ones seem to be ok, the older ones were a roll of the dice. For the money, I would still pick a Caspian.

Jim Watson
May 16, 2004, 01:05 PM
My most used 1911s are on cast Caspian frames. Fitting is close, loads are moderate, and springs are fresh. They have been holding up for some years, now.

Harold Mayo
May 16, 2004, 05:15 PM
YES, Sean!!:D

Straight from the "other" board. I was going to go over and look up that information.

I do NOT buy into a forged frame being twice as strong as a cast frame.

In my business (mining), I see EXTREME stress placed on metal parts. I see no difference in parts that happen to be forged over those that are cast. As a matter of fact, the vast majority of parts that are designed for high-stress environments are cast rather than forged.

Of course, as Sean said, it all depends on the manufacturer and material and process choices.

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