Model 442/642: steel cylinder/barrel, aluminum frame, 15ounces

Model 340PD: titanium cylinder, steel barrel, scandium frame, 12ounces

Model M&P 340: steel cylinder/barrel, scandium frame, 13.5ounces approx.

Put those in there for reference... So between the 642 and the M&P 340, for example, the weight you save is about 1.5 ounces. I personally really can't tell the difference very well. So how does the strength of the aluminum frame compare to scandium? Obviously, the 442/642 cannot fire .357 magnum but that's irrelevant to many people (including me) in this light of a revolver I think.

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Aaron Terry

According to Smith & Wesson, the small amount of scandium added to the aluminum alloy makes it stronger than their aluminum frames without scandium.

My 340PD and 360PD (each about 11.8oz) have a combined total of +7K rounds of loads that are midway between +P and .357. Both are tight as the day I bought them. I don't believe regular aluminum frames hold up that well.

Unless one is going to shoot Magnums, I believe the aluminum frames of the 3 digit model number J frames (442, 642, etc) to be plenty adequate for extensive use. I carry a M-642 I bought in 1991. I have shot more than 2,500 rounds of factory Plus-P through it, plus probably that many standard pressure loads (both factory and handloads) and it is just fine. They hold up far better than many expect.

I think the major consideration to the buyer is, does the slight extra strength of the scandium frame make up for the added cost?

Correct me if I'm wrong, but I'm fairly certain that I read somewhere that the hogue grip used on the 340's was about an ounce lighter than the uncle mike's grip used on the 442/642. If that is the case, than the difference in weight for adding scandium to the frame is closer to half an ounce, not 1.5 ounces.

So you're saying the 340 is an aluminum frame with a small amount of scandium added?

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Aaron Terry

Of course. The only known usage of Scandium is as an additive to aluminum alloys. While I'm not sure what concentration S&W uses, I do know that the normal amount of scandium used to strengthen aluminum is usually less than 0.5%.

P.S. If they could find a way to make a frame entirely out of scandium, you could probably expect the retail price to be in the 100's of thousands per unit. It is an exceptionally rare element.

Never realized that. Guess I should have paid more attention in physics class in college

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Aaron Terry

I think the price of Scandium was $3500 a pound a few years ago. The weight of the frame alone, not including lockworks, cylinder or barrel or grips is probably only 6 or 7 ounces a the top. Meaning you'd have well under a pound used.

But as I understand the metal, it doesn't make a good frame by itself. Its subject to corrosion. But alloyed with aluminum, you get almost all of the strength characteristics at a much lower price. It would be nice if S&W were to publish some of the tensile strength numbers.

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Dick Burg

I see little need to debate how or if scandium makes it stronger and by how much. My EDC is a 386 Mountain Lite (customized of course) and at about 19 ounces, .357 Mag and a seven shooter I think the scandium is the bees knees. Plus, Smith and Wesson has engineered it better then any forum theorists can. Add in the lifetime warranty and I am sold. (I have three scandium framed revolvers)

The only problem with the Scandium guns (other than cost, arguably) is the lock. But that's a whole other can of worms.

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Aaron Terry

Aw. The locks not a problem. They've been known to fall right out of the action. The offending spring, flag and all. Just as common is the little nub that cams into the hammer recess has been known to get in the way of the grinder and just vanish.

Son says "Dad, why doesn't the lock work?" Response: "foolish boy, it took hard work to get it that way. Prolly 15 minutes worth."

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Dick Burg

Well, this clears it up for me!

scandium


When added to aluminium, scandium substantially lowers the rate of recrystallization and associated grain-growth in weld heat-affected zones. Aluminium, being a face-centred-cubic metal, is not particularly subject to the strengthening effects of the decrease in grain diameter. However, the presence of fine dispersions of Al3Sc does increase strength by a small measure, much as any other precipitate system in aluminium alloys. It is added to aluminium alloys primarily to control that otherwise excessive grain growth in the heat-affected zone of weldable structural aluminium alloys, which gives two knock-on effects; greater strengthening via finer precipitation of other alloying elements and by reducing the precipitate-free zones that normally exist at the grain boundaries of age-hardening aluminium alloys.

The original use of scandium-aluminium alloys was in the nose cones of some USSR submarine-launched ballistic missiles (SLBMs). The strength of the resulting nose cone was enough to enable it to pierce the ice-cap without damage, and so, enabling a missile launch while still submerged under the Arctic ice cap.

I'm sold on the scandium framed guns as well,they are stronger and can operate at much higher pressure levels than a conventional aluminum alloy frame can.

This is why they can chamber guns like the 340 series in .357 magnum. As we all know this round has a much higher PSI than even .38 special +p+ loads do. All that being said I love my 340PD I think its the best carry gun I've ever owend,and I've owned/carried pretty much all of them.

All that being said given the intended role the 642/442 play,will anyone here ever shoot them enough to wear them out? I would think that the service life of a modern alloy framed gun rated for +p ammo would be quite long. I do feel the 340/360 series is worth the money for everything they bring to the table not just their .357 magnum chambering.

Mine is on my right hip as I type this and I have to check its still there as its so light,its sick it feels like a toy or something. I have it loaded with Remington 125gr .357 golden sabers. I'm carrying this and a speed loaded with the same ammo in shorts and a T-shirt,its 87 degrees here in south florida today. This gun allows me to carry a .357 magnum for SD in summer clothes. It is an expensive gun yes but I still believe that it is unmatched in the power/size/weight area.

I'm not sure if I fully agree with your facts, but I do agree with the conclusion of them being great guns.

The pressure problem relates more to the cylinder and forcing cone than to the frame on a revolver. As we know, the barrel and forcing cone are traditional Stainless Steel. The cylinder, where the pressure is most severe, isn't made of the Scandium, but instead titanium. I assume in reality both are made from some alloy of those materials, and I'm clueless as to what other material the cylinder may include.

What makes the guns easy to use is the weight, and both the frame and cylinder are significantly lighter than conventional handguns.

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Dick Burg

My 340PD has more than 5000 factory magnum rounds through it. It also is still nice and tight.

Scandium firearms are VERY strong compared to their aluminum counterparts. Without Scandium there would be no lightweight 41 or 44 Magnums.

Right now between my 340PD, 360PD, 327s, 310 and 625s, I must have a dozen Scandium revolvers. I owned a few 386s as well, but replaced them with 327s for the extra shot.

I've seen several reports in the past, of 38 +P+ stretching the frame of "ordinary" aluminum guns like the Model 38; to the point of misfires from excesive headspace. Sometimes, just a few hundred rounds.

Pure Scandium is several thousands of dollars per ounce at the moment. However, it is too soft to be used in it's pure form. The strength comes from alloying it with other metals like Aluminum.

rburg your correct in that the cylinder and forcing cone that takes the brunt of the pressures. what I was saying is that I believed that the scandium mixture allowed the gun to be chambered in the more powerful magnum cartridge. I do feel like these gun are more durable than their aluminum alloy siblings. I do love my 340PD I think it an awesome gun with a definite cool factor as well. I've referred to it as "a miracle of modern creation" as it is truly a cutting edge product made from space age exotic alloys.