[black_powder_Rob]

Do the ultra light frames stretch out and widen the gap between the cylinder and the forcing cone? I was looking at one the other day and it seemed interesting to and I was thinking about getting it but I wasn't sure about the frame. Any advice? Or experiences, thanks for the input.

[Old Fuff]

If you mean recent production models chambered in .357 Magnum, the answer is probably "no" - mainly because an owner probably won't shoot enough Magnum loads to do the dirty deed. However cylinder endshake is a real possibility, and a few of them have been known to send a barrel downrange when the barrel threads failed to hold. There are also some other issues associated with titanium cylinders. I've made a point of staying away from them, but to each his own... :scrutiny:

[jfh]

I know of no objective data on this topic, but my conclusion is that

1. Today's aluminum-framed lightweights are noticably superior to the early ones, and

2. The strength of the S&W scandium-framed revolvers is about equivalent to the steel ones.

With that in mind, the wear-out factor probably depends on the typical variables: A S&W 442 frame will probably stretch faster if fired with "max" 38+P ammo, and certainly will with over-pressure handloads. I owned one briefly, and in the few hundred rounds I shot in it--mostly max-pressure 38-CIP reloads--there was no change in the b/c gap.

I have shot about 2000 rounds through my M&P340. The great majority of these rounds were reloads to nominal 38+P pressures, but 357 reloads with 158-gr. LSWCs running at about 900 fps were also shot. (That's about the limit of my recoil tolerance and hand conditioning.) The b/c gap is unchanged on this firearm.

My stainless 640 has about 18,000+ rounds through it now. Again, the majority of rounds were 38-CIP pressure reloads, or lower-pressure 357 reloads. However, it has had some 357-max reloads shot through it, and early on (about rounds 300) five grossly-overpressure rounds were fired through it. S&W replaced the cylinder and returned it to me. The forcing cone shows no erosion to my untrained eye, and the b/c gap has increased by .002. I consider that normal wear.

Note that for S&W, their revolvers come with a 'lifetime' warranty, at least to the original owner. I imagine that if you actually shot an Airweight (aluminum) framed gun so much that the frame actually stretched, then S&W would 'repair' it for you, probably at no charge at all.

In the end, then, the decision as to which lightweight firearm to get probably rests mostly in the buyer's personal values regarding purchase price, QC / pride of ownership, actual practice / quantity shot, etc., etc. This is another way of saying that the Scandium-framed lightweights are built to better QC standards and have typically more desirable details, such as front sight options.

Jim H.

[xstuntman]

I've seen several threads where the barrel departed for greener pastures so I've stayed away from the lighter materials so far. I've also heard from several people that they'd recommend only standard .38 loads for the lites which I don't consider an issue, just something to think about.
There doesn't seem to be a lot of information concerning longevity for lites vs the steel versions which has left me in the dark. :banghead: X

[ArmedBear]

Yeah. This happened when I shot some Buffalo Bore loads.

http://www.cabelas.com/cabelas/en/content/Item/61/51/31/i615131sn01.jpg

[MCgunner]

Not mine, not so far. I practice with standard pressure and it's +P rated.

[rcmodel]

Dick Metcalf & Shooting Times did a 5,000 round torture test on two S&W Airweight Chiefs Special revolvers years ago, not long after the SAAMI +P pressure spec came along.

Each aluminum frame revolver was measured every whichway before firing, then every 500 rounds after, until they each had fired 2,500 rounds of +P ammo.

At the end of the test, there were no measurable changes in anything.

The only thing that changed was:
1. Slightly higher velocity at the end of the test.
2. Slightly better accuracy at the end of the test.
3. Better trigger pulls on both guns.

rc

[KBintheSLC]

I assume if you load it with the hottest ammo on the planet and run many thousands of rounds through, you might increase the gap by a few thousandths of an inch... or other issues might occur as others have noted.

I generally make it a habit to practice with light loads, and carry warmer standard pressure loads. The +P stuff just doesn't add that much to my 38 spl in my opinion... except for recoil and muzzle flash.

[Jim K]

All revolver frames stretch on every shot. But as long as the elastic limit is not exceeded, they will come back every time.

The problem with break top guns is that the joint acts to allow free movement (no matter how tight it feels) which will eventually cause battering and looseness.

Jim

[ArmedBear]

All revolver frames stretch on every shot.

This is why it's really important not to put your finger between the cylinder and the forcing cone when you fire the gun.:D

[unspellable]

Revolver frames don't stretch period. Or rather, as stated above, they strecth on firing and then spring back to the original dimensions. End shake develops for other reasons. Cylinder gap does not increase when end shake develops. In fact it will appear to decrease at a casual glance, while proper measurement will show it to be unchanged. The most common cause of excessive cylinder gap I've seen is poor fitting at the factory.

As an example, in the S&W the end of the yoke tube has a very small area that bears on the bottom of the cylinder well to limit forward movement of the cylinder. Under heavy usage the end of the yoke tube gets battered down while the bottom of the cylinder well develops a groove. Then you have end shake. This is really a weak point in a S&W and I have long wondered why they don't change this. It would require a rather minor design change. mean while, S&W will stretch the yoke tube for a one time fix for end shake. It can also be fixed by installing shims which I think is the better method.

A Ruger Blackhawk on the other hand limits forward travel of the cylinder by way of the cylinder neck bearing on the frame with a much larger area. So same load for same load, it will take the Blackhawk longer to develop end shake than the S&W.

An aluminum cylinder of S&W type will be softer and develop a groove sooner.