Newbie revolver question

A

AndyM

Inactive
Hi Folks,

Just joined TLF today after lurking for about a month.

All I can say is that the more I learn, the more I realize how little I know. :)

While trying to learn as much as I can about revolvers, I have come across a question that I imagine can be answered here in about 2 seconds.

A lot of people mention revolvers as being "pinned and recessed."

I see this description applied to S&Ws quite often but don't know if this is particular to S&Ws or not.

What exactly does "pinned and recessed" mean?

I suspect "pinned" referrs to an actual pin being put in somewhere.
However, I don't know what is being recessed.


Does this exist on only particular models/brands?
Is this something people have done to the pistols?
Is it an enhancement or a repair?

Is a pistol that has been pinned and recessed more or less desireable? I suspect more desireable.

Just pretty much clueless all around on this subject.
(and a bunch of others by the way) ;)

Thanks for the info.

Andy
 
Pinned refers to the barrel being pinned into place in the frame. Most revolver barrels are simply screwed in.

Recessed is a counterbore drilled at the back of the chambers so the cartridge rims can fit into them.

Both of these take more time in manufacturing and are usually associated with higher quality and/or custom guns. As to actual benefits, I'll leave that to those who are more knowledgable.
 
"P&R" refers to S&W revolvers. The old ones in Magnum calibers had "recessed" chambers, counterbored to enclose the cartridge rims. Note that non-Magnums did not have this so no .38 Special, .45 Colt, etc S&W revolver was ever "recessed." Only the .357, .41 & .44 Magnums.

The "pinned" refers to the barrel being held in place by a small pin driven crossways through the frame. All S&W revolvers had this. Both features were fazed out around 1980 or so. In reality neither feature made any difference in the performance of the gun, but were indicative of a general lessening of overall quality. Most shooters will pay a premium for "P&R" guns, and some (like me) avoid the newer ones entirely.
 
S&W's .22s were also recessed. They continue to be, in one form or another.

When the barrel pin was dropped, the barrels had to be screwed into the frame more tightly to ensure that they didn't start to back out.

This has led to some revolvers actually coming from the factory with overtorqued barrels, which can lead to both frame and barrel problems that may or may not cause shootability problems
 
P = pinning of the barrel to prevent the barrel unscrewing (from the frame) under the torque of the fired round.

The barrel is screwed in normally to the frame & then a pin driven through a pre-drilled hole to prevent the barrel torquing out under the round's torquing & unscrewing the barrel from the frame under stress of firing the round.

Knowing absolutely nothing other than that, seems that the whole thing could have been prevented (if any problem at all) by having the barrel threads opposite that relative to the rifling = when the thing fired, the barrel would torque tighter to the frame.
& that could possibly cause a tighter fit relative to cylinder clearance ... maybe it's a good idea ... ?

But I'm just some guy = what do I know? ;)

Recessed? I have no idea as to anything functional.

I've a couple & glad I do. Lots pay more money for both.
 
Mike is correct about the rim fire revolvers being recessed. I forgot to note that.

On the stressed barrels, I have no knowledge of this. I would point out that other revolver makers, such as Colt, never pinned their barrelas and they don't seem to have this problem.
 
Recessed chambers are a safety feature on the rimfire rounds - remember the rim is crushed to set-off the primer, and sometimes they split releasing hot gas. This is very rare in modern ammo, but was a constant problem in the old Henry 44 rimfire with it's copper (not stronger brass) case. Recessing the rim into the cylinder helps contain this gas - at least it doesn't get a straight shot out but has to "turn corners" - giving it a chance to dissipate some energy and pressure. S&W made the original 357 Magnums this way also - I guess they were afraid of the pressures they were using (47K CUP originally, now SAAMI spec is down to 35K CUP) that were 2-3 times that of any previous cartridge used in a revolver. They just kept doing it for the newer magnum cartridges as they were introduced even though there really wasn't a need for it.

Pinned barrels allow the barrel to be just finger tight in the frame - torqueing the barrel in the frame causes a "tight spot" to develop as the bore is squeezed by the threads. This can be harmful to accuracy and can cause leading/copper fouling as the bullet is pressure fitted to the start of the bore, which then gets a little bigger for the rest of the length of the barrel letting hot gas flow past the bullet. This was a desirable feature that I really wish S&W would bring back.
 
"Pinned barrels allow the barrel to be just finger tight in the frame ... "

I didn't know. Thought it'd be standard "wrench-tight" & does make some sense. Thanks, Chris.

'Nother reason to at least surf the handgun threads - wealth of info here ....
 
"Pinned barrels allow the barrel to be just finger tight in the frame ... "

I didn't know. Thought it'd be standard "wrench-tight" & does make some sense. Thanks, Chris.

'Nother reason to at least surf the handgun threads - wealth of info here ....

Just as a gee-whiz type query, what's a P&R value over same-same that's not?
 
the rifling twist on colt barrels twist the opposite direction from smiths...so i guess you could say "colt barrels are self tightening"...they also twist at a different rate (at least in .357/.38), 1-14" vs 1-18"
 
I believe the older centerfire cartridge cases were made with folded rims, much like a rimfire case, and the recessed rim for a revolver chamber was a safety feature for the center fire cases as well. Now that centerfire cases have solid rims the recessed feature is not as important for safety. You'll sometimes come across mention of the folded head cases when writers try to duplicate blackpowder loads in modern cases-the solid rim cases don't have the capacity of the folded cases.
 
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