Do All Revolver Frames Stretch?

[Gun1]

was told by a gunsmith that all revolvers will eventually have their frames stretched if enough rounds are shot through them. However, I'm wondering if it has more to do with material, such as aluminum vs steel, or if I shoot only 38 special out of a revolver made for 357 magnum, would that still stretch the revolver frame, it would just take significantly longer?
I've spoken twice to S&W and Ruger. Both S&W reps told me that stretching would affect more the lightweight revolvers than a heavy steel one, but that even in the heavy steel ones and even if shooting light loads rather than heavy hot loads, if shot enough the frame would eventually stretch. However, Ruger said this was an old myth from when revolvers were made from brass, that the new ones don't stretch at all regardless of what you shoot through them, and the second Ruger CS rep said that their frames didn't stretch at all regardless of what you shoot through them because they're heat treated.
So, I was wondering if anyone has any experience with frames stretching with these particular brands? Either Ruger is vastly superior to S&W or Ruger CS reps we're completely truthful?

 

[JohnKSa]

I think that any failure mode related to frame strength in modern revolvers is pretty unlikely these days. They will still wear out if shot enough, but it isn't likely to be because the frame stretched/cracked/broke.

 

[Gun1]

I think that any failure mode related to frame strength in modern revolvers is pretty unlikely these days. They will still wear out if shot enough, but it isn't likely to be because the frame stretched/cracked/broke.

So if shot enough what will wear out, replaceable parts like the barrel, pins, springs, things like that?
But as far as the actual serialized portion, the actual receiver, stretching or cracking or wearing out, even with something like 500k rounds or so, not likely?

 

[JohnKSa]

The lifetime of the gun and the type of failure it eventually displays will depend on the revolver, how it is used and maintained and what kind of loads are used. Some will eventually crack forcing cones, others might have small parts break or wear, rifling could wear, some might develop end-shake from heavy recoil and/or a more delicate design.

But...

If you can afford the tens of thousands of dollars it will cost to put 500K rounds through a revolver, you really don't need to be worrying about paying to repair/replace the revolver someday or the cost of keeping a spare on hand.

 

[balin]

With laws of physics being what they are with the amount of force pushing the bullet down the barrel. There is an equal force smashing the casing into the frame. With enough rounds there is bound to be stretching. Guy's like Gerry Michulek can shoot a gun for years without wearing out the frame. If you look at hi speed films on Glocks shooting 10mm rounds you can see stretching going on, but those frames snap back and after 10's of thousands of rounds they are still dimensionally the same.

 

[UncleEd]

Over the decades from 1870 to the
present, metallurgy has improved
tremendously in cartridge firing
guns.

What was excessive use and
pressures on a
particular model in 1950 is no
longer true for the same or
similar model in 2022.

I suppose, yes, if you're a
"combat" shooter who measures
performance by how much ammo
is used up, then of course a gun's
parts will wear out sooner. And
that could mean the frame too.

 

[Barbaroja]

But...

If you can afford the tens of thousands of dollars it will cost to put 500K rounds through a revolver, you really don't need to be worrying about paying to repair/replace the revolver someday or the cost of keeping a spare on hand.

nail on the head!

 

[Archie]

The primary 'wear' to a revolver (aside from bore pitting from ignoring the problem) is the top strap of the frame stretching. However, it is a slow process. I have a S&W model 13 with a stretched frame (top strap). The muzzle gap (between cylinder and barrel) is larger than it was when new (yes, I measured). The main "symptom" it shows is a propensity to project lead and grains of gunpower (usually burning) sideways from the gap. (Which made me less than popular on the firing line.)
Truthfully, I have no idea how many rounds I had fired before this was realized. A goodly number of .357 Magnum rounds and gobs of .38 Special - ranging from Wadcutters to +p loads.
It appears I can fix this by having the barrel removed and set back to correct the excess gap.
At the time of all this, the S&W L frame was released. Instead of working on the K frame, I bought a fixed sight four inch L frame (model 581) and retired the model 13. I still have both.

 

[Anchorite]

The lifetime of the gun and the type of failure it eventually displays will depend on the revolver, how it is used and maintained and what kind of loads are used. Some will eventually crack forcing cones, others might have small parts break or wear, rifling could wear, some might develop end-shake from heavy recoil and/or a more delicate design.

But...

If you can afford the tens of thousands of dollars it will cost to put 500K rounds through a revolver, you really don't need to be worrying about paying to repair/replace the revolver someday or the cost of keeping a spare on hand.

Nailed it.

 

[highlander 5]

Not a metalergist but you have to define "stretch". I think of a rubber band with the word stretch. How much does a frame stretch with each firing and I suspect the frame has some elasticity designed into it but all in all it would take a long time and a very large ammo supply to get measurable results.

 

[UncleEd]

As I've often stated, I love the S&W
Combat Masterpiece .38 and the
ones I do shoot really don't see all
that much action. They are, of
course, K-frames.

But if I were to be back into volume
shooting, then the L-frame would
get more use. I think of the L-frame
size to include the Smiths, the
GP100s and the Colt Pythons
(I frame to be accurate).

 

[Slamfire]

I am going to say, I will bet that the frame, and the cylinder, both stretch when a cartridge is fired. We know the cylinder stretches because we all have had stuck cases, which happen due to over stretching between case and cylinder.

But, and this is the big butt, all this stretching is in the elastic limit of the material. As long as the stresses are below yield, which is permanent deformation, than the frame/cylinder will relax back to original, pre firing dimensions.

A different issue is fatigue. You can build a steel structure thick enough, heavy enough, the structure will not fatigue fracture. Loads have to be below yield, in fact below yield by certain levels. This results in heavy structures. However, no one wants to carry a heavy firearm, so in time all firearms have some fatigue fracture limit at some number of load cycles. The heavier the load, the sooner the material will fatigue fracture.

Just what is that number of load cycles? Heck if I know. You shoot very light loads, a K frame steel framed revolver will last an incredible number of rounds. A 10 time PPC champ told me he had 600,000 rounds through one of his K frame pistols. He had worn out extractor stars, I assume the cylinder hand and internal parts were replaced at the same time. He had a firing pin break. I am sure he had replaced a number of mainsprings, and internal springs, those things wear out. He shot 148 LWC with 2.7 grains Bullseye (mostly I assume, I am sure there were some other rounds fired). But the cylinder and frame were still ticking. Another shooter, he said he had about 250,000 rounds through his K frame pistol in Bullseye Competition.

Aluminum causes problems, no matter how thick the piece of aluminum, eventually it will fatigue fracture. One reason aluminum aircraft have rebuild cycles. At some number of flights, the main spars will crack and the wings will fall off.

I could not believe someone had made all aluminum FAL receivers. FAL's are rear lockers, and someone built a receiver where the load was carried by an aluminum receiver. It was only a matter of time till the receiver cracked.

WARNING! Aluminum Uppers
https://www.dsarms.com/t-aluminumwarning.aspx

only took 189 rounds to come apart!



I believe for aluminum framed pistols, the fatigue lifetime of the frame would be in the realm of tens of thousands of rounds. This poster was experiencing severe frame wear in 5000 rounds

S&W Model 642 is wearing out! Possible fixes?
https://www.thehighroad.org/index.php?threads/my-s-w-model-642-is-wearing-out-possible-fixes.904895/

I have no idea about fatigue lifetime for polymer pistols. No idea about the fatigue lifetime of plastic parts. I don't own any tupper ware pistols at the moment. Don't want one. Bah!

As much as we want, nothing lasts forever. Rain erodes mountains and they flow to the sea. Shoot enough rounds through your pistol, you will experience wear. Depending on the pistol, somethings will break. Some of those things that break are cheap and easy to replace, others cost more. As a general rule, with today's materials frames, slides, materials, should outlast you. But there are exceptions where the tradeoff is weight. You want light, it is not going to last as long.

Ask those who used to run race cars. That Chevy small block which goes 100,000 miles at 235 hp, may go a couple of passes down the track at 800-1000 horsepower. The engine is then rebuilt, or scrapped.

 

[jmorris]

If you had the ability to actively measure in very, very small units, you would find that they do stretch and return to position. Rifle barrels even “whip”.

Yielding (staying stretched) is different, that you could measure after firing and would just get bigger and bigger the more you shoot. Mine do not do that but I haven’t gone over published data in more than 30 years now.

 

[Jim Watson]

At one time Colt thought to offer a Detective Special .357 Magnum but test articles had significant topstrap stretching.

 

[mcb]

Modern closed frame steel revolvers are almost certainly operating under the infinite fatigue life of the frame material. If stress/strain is kept under this limit you will not get stretching or even fatigue failure of the material. I have three N-frames that I have used for USPSA competition. All three were bought used and I know one of them had multiple owners before me. I put well over 20,000 rds through a S&W 610 and over 10,000 through a 625 (and I was at least the third competitive shooter to own this revolver) and a 627 that is closing on 10,000 rds. The frames are fine. You are going to wear out cylinder stops/notches, pawls, stars, and other internal parts out long before to stretch or fatigue most modern revolver frames. You will probably shoot a barrel out before you have a frame failure. Aluminum frames are another animal and you do see stretch or cracked aluminum frames but most steel frames will out last most of the other components in the revolver. Flame cutting a frame is a bigger threat than stretching it.

 

[Gun1]

Modern closed frame steel revolvers are almost certainly operating under the infinite fatigue life of the frame material. If stress/strain is kept under this limit you will not get stretching or even fatigue failure of the material. I have three N-frames that I have used for USPSA competition. All three were bought used and I know one of them had multiple owners before me. I put well over 20,000 rds through a S&W 610 and over 10,000 through a 625 (and I was at least the third competitive shooter to own this revolver) and a 627 that is closing on 10,000 rds. The frames are fine. You are going to wear out cylinder stops/notches, pawls, stars, and other internal parts out long before to stretch or fatigue most modern revolver frames. You will probably shoot a barrel out before you have a frame failure. Aluminum frames are another animal and you do see stretch or cracked aluminum frames but most steel frames will out last most of the other components in the revolver. Flame cutting a frame is a bigger threat than stretching it.

So with these revolvers the frame should never stretch or crack, even with 357 magnum loads?

 

[mcb]

So with these revolvers the frame should never stretch or crack, even with 357 magnum loads?

Yes most modern steel revolver frames should not stretch or crack without some other contributing factor. There are caveats. There are know flaws in S&W K frames that can be exploited by 357 Magnum levels of stress and we do see K-frames crack around the barrel but usually in conjunction with a forcing cone crack. New K-frames have changes to help mitigate this.

For most modern steel framed revolvers there are many far more likely failure modes than frame stretch.

 

[Jim Watson]

I have too many pistols in even the match "rotation" to actually wear one out. Maybe if I had kept that 1975 Gold Cup.
The only breakage I recall is a couple of 1911oid firing pin stops.

I shot a lot of Trap, most with a Remington 1100. Good stock fit, soft recoil, good patterns. But not durable in competition, I think receiver and stock are all that remain. The original barrel is ok but the little bit I shoot it now is with a different one.

 

[Ethan Verity]

I have over 4k rounds through my S&W Model 642 J-frame. The main area of wear I noticed was the center pin hole ovaling out. It's so bad now, that the cylinder actually hits the frame during recoil! However, it's still in time with no lead spitting, so I just keep on using it. I theorize the wear has stabilized now that the cylinder is stopped by the frame.

I checked the cylinder end shake with a feeler gauge, and to my surprise it's still in spec! So even in this instance of excessive wear, the frame isn't stretching.

 

[Bill M.]

My thought is that the forces on the revolver frame should be under the elastic limit for the frame material. So...it really should not "stretch" in the sense that it becomes longer permanently. It should take loads over the cartridge limits to do that kind of damage.

 

[Mizar]

I theorize the wear has stabilized now that the cylinder is stopped by the frame.

The rearward motion of the cylinder in almost every revolver (excluding Nagant and the like) is always stopped by the frame via the ratchet. What you see there are cartridge heads imprints from recoil and it's quite normal for aluminum framed revolvers - it doesn't mean that the cylinder is pushing them against the recoil shield. If the cylinder was actually hitting the frame (breech face & recoil shield) via the cartridges, you would get three clues - heavy imprint of the ratchet on the aluminum frame, insufficient headspace resulting in hanging when closing a loaded cylinder and excessive endshake.

 

[Ethan Verity]

The rearward motion of the cylinder in almost every revolver (excluding Nagant and the like) is always stopped by the frame via the ratchet. What you see there are cartridge heads imprints from recoil and it's quite normal for aluminum framed revolvers - it doesn't mean that the cylinder is pushing them against the recoil shield. If the cylinder was actually hitting the frame (recoil shield) via the cartridges, you would get three clues - heavy imprint of the ratchet on the aluminum frame, insufficient headspace resulting in hanging when closing a loaded cylinder and excessive endshake.

No, the bottom edge of the cylinder is smacking off the bottom of the frame right behind the cylinder stop. So, it's no longer egging out the center pin hole.

 

[Mizar]

o, the bottom edge of the cylinder is smacking off the bottom of the frame right behind the cylinder stop. So, it's no longer egging out the center pin hole.

This is something not evident by the pictures in your first post - I feel sorry for the little bug, but if it's still shooting...

 

[Jim Watson]

If they wanted to make a high volume Airweight it should have a steel bushing for the center pin hole.

 

[Mizar]

If they wanted to make a high volume Airweight it should have a steel bushing for the center pin hole.

And people will start complaining about the price increase...