Frame-mounted vs hammer-mounted?

Frame mounted pin is old style, pre lock.

I prefer hammer mounted, but both work.

Assuming all things are equal, get the hammer mounted firing pin. One is that they don't make them anymore and thus it will have a slightly higher future value.

The other is, well there might very well be a functional difference between the two. And that is a direct strike mechanism is going to deliver more energy than a mechanism that has to transfer energy through something. Now the S&W's have strong mainsprings and all, but the more energy on target, the less the chances of a misfire. I have had them with my reloads. Might have been poor Quality Control, but I might have had more with free floating firing pins.

When I talked to S&W, they removed the hammer firing pin because it took a special machine with a dedicated person to mill/drill the frame notch.

Perhaps I missed something here.... A frame mounted firinng pin on an L frame would be a newer gun, mim and everything. The hammer mounted firing pin is on the "older" L frames-pre mim/lock.

I like the frame mounted firing pin better--very easy to change, much easier than the hammer mounted firing pin, tho I do both.

I have several frame mounted FP guns, and only a couple are 'lock' guns.

Hammer-mounted firing pins are a little more delicate, easier to break (turning the gun into a doorstop).

BUT, when you go to a frame-mounted pin you usually also go to a transfer bar safety over a hammer block. Transfer bars are OK but since there's an extra piece of metal involved in the energy transfer, you have to run a mainspring that's about 20% - 25% stronger.

So, a hammer-mount-firing-pin gun can in many cases have a slightly sweeter trigger feel than a frame-mount gun.

THAT said, a really good frame-mount gun can be pretty damned good. So it's not a universal thing. It is however a "trend".

I own three frame-mount guns and no others. So my choice comes down in favor of reliability.

BUT, when you go to a frame-mounted pin you usually also go to a transfer bar safety over a hammer block. Transfer bars are OK but since there's an extra piece of metal involved in the energy transfer, you have to run a mainspring that's about 20% - 25% stronger.

Click to expand...

This is not a concern for the gun in question however.

I like the hammer mounted FP better. It completes the look. Although S&W has introduced post hammer mounted FP guns that I needed to have so I've learned to accept frame mounted as well.

The hammer mounted pin is classic S&W. If you have a choice go that way. I have 30 year old Smiths that have never broken the hammer mounted firing pin.

With the exception of rimfire models, most pre-MIM Smith & Wesson revolvers had hammer mounted firing pins. Thus the hammer vs. frame mounting is sometimes used as a point of identification.

On the practical side, a frame mounted pin requires less metal be removed from the breech area, particularly that which is directly behind the cartridge case head. Generally this may not matter, but it does when you make aluminum-framed snubbies chambered in .357 Magnum...

So far as cosmetics are concerned, whatever "look" you like is... what you like.

I'm not up on the S&W history enough to know if they produced guns with both styles of firing pins "pre-lock" & "post-lock".

Whatever the style, I'd take a pre-lock gun first. If both were available without a lock...eh....who knows......I guess it would depend on condition, price, etc...

The first generation PC 627 models are non-lock and have the frame mounted firing pin.

Rick

All of the smith and wesson K and J frame .22lr revolvers have frame mounted firing pins, at least my 1956 k22 and my 1973 model 43, do.

The hammer nose firing pin was on centerfires, S&W rimfires have always been frame mounted firing pin guns.

There were lots of Smiths with frame-mounted pins before the locks. I've had dozens of them.

If you install a light hammer spring you may not have reliable primer ignition - this is much more of a problem with frame mounted pins than hammer mounted - but there is a solution - you can get an extended frame firing pin that will increase reliability. This is what I did with my 686 that I shoot SSR in IDPA - Federal Primers are recommended - they are more sensitive and CCI are considered less sensitive.
On an old K frame with a hammer mounted pin I was able to go light with no ignition problems. Personally I think revlovers are kind of retro fun anyway and the hammer mounted pin even more so - classic.

Though we are talking Smiths here, bear in mind that Colt double-action revolvers have had frame-mounted firing pins for decades (non-pinned barrels, too.)

I'd rather have a frame mounted firing pin with the transfer bar system of lockwork. I feel it's safer than a hammer block and hammer mounted pin for carry, though not enough to really lose sleep over and it's not a biggy with me. I carry an old pinned barrel M10 now and then and don't worry about it and I have a Rossi 68 with the same lockwork that works fine and I feel safe with. I did have a problem with a hammer mounted firing pin once. They can break and aren't real dry fire compatible, but then, I've heard of firing pin return springs sticking or breaking, too, though I've never had it happen on me. I used to dry fire my Security Six silly and I never worried about the firing pin. I'd never do that without snap caps in the M10.

All of the revolvers that have transfer bar safeties have them, and nothing else. Colt and S&W revolvers that use (or used) a hammer block had two independent safeties. The first rebounded (retracted) the hammer backwards and then blocked it from moving forward. A second independent hammer block inserted between the frame and hammer, just below the firing pin acted as a backup for the first one.

Both systems (hammer block and transfer bar) do the job, but in theory, if not practice, the Colt/S&W system is a bit safer.

With the Ruger transfer bar, unless the bar is in the way, no way it will fire. If the transfer bar were to snap, it would just not fire. The hammer hits the frame, not the pin, by default. If the hammer block fell out or snapped and the hammer were to be driven forward, by dropping on it, you could have a fire. However, yeah, near impossible in either case and is really moot except in theory. I do think the transfer bar system is a little tougher, but that's probably because I've had a hammer mounted firing pin fail before.

In a S&W or Colt revolver if the hammer block breaks - which is unlikely, Colt's introduced their version in 1908 and S&W in 1945 - and neither have a history of problems, the rebound safety would still block the hammer from forward movement.

A broken firing pin is another, and unrelated issue.

On rare occasions, Ruger revolvers have been known to break a transfer bar, after which the gun can't be fired until it's replaced.

All of this of course is nit-picking. In truth both systems work well.

Two different philosophies at work? One fails safe by preventing firing and the other fails safe by allowing firing but not protecting against a hammer blow? Just a theory, but I can bet which one the lawyers would prefer.

Rick

No, both prevent an accidental discharge caused by a blow to the hammer (such as dropping the gun on a hard surface). Neither will fire unless the trigger is held back while the hammer is falling. In either case if the hammer is cocked but accidentally falls while the trigger isn't held back, the trigger will follow the hammer forward, and no discharge will occur. Unless the safety(s) have been tampered with a lawyer has no way too go.

IIRC the .22 Jet with frame mounted firing pin was sought after.

IIRC the .22 Jet revolver was once - long ago when it was unusual among S&W revolvers in having a frame mounted firing pin - the hot choice of frame for PPC and other game conversions because of the frame mounted firing pin.

There is an argument that the frame mounted firing pin is less likely to tie-up from a primer blowing back into the firing pin hole - not a common cause of problems for most users but an issue for some games and some reloaders.

I'd look beyond the question of frame or hammer mounted firing pin to make a choice between 2 - I'm perfectly happy to carry an N-frame with frame mounted firing pin and crane mounted lock but I'd also cheerfully swap a brand new 657 for the Model 58 I carried long ago and sold to pay the rent during hard times.