Howdy, been away for a while but I knew this would be the place to get an answer. My question is in general regarding the design of the top latch. I've become interested in the small pocket pistols of the late 19th and early 20th century. Most of these are break top designs and most of the latches are of the inline design which I consider a very poor design since the latch itself must take the thrust of firing. I've always thought a much better design had a mortise in the extended top strap to close over a raised stud on the standing breech so that the latch need only hold it down. That makes a lock up as strong as a solid frame. Examples would be the Scofield and the Webley revolvers. Some few American top breaks also employed this design. I see that the S&W Safety Hammerless had a similar latch at one time but by far the most employed the common weak inline latch. I'm wondering which models employed the stronger latch setup?
I've attached a photo (if it works) of a cracked latch and bent latch screw from a cheap top break which shows the weakness of that design

Attached Images

Cracked top break latch.jpg (67.3 KB, 153 views)

Welcome to the forums from the Wiregrass! I can't answer your question but I'm sure someone will be along shortly who can.

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Guy
SWHF #474 SWCA LM#2629

Thanks for the welcome. From what I'm seeing on internet photos there appear to have been at least three different latches tried over the several generations of the Safety Hammerless.

The 1st & 2nd Schofield, 1st .38 Safety and the 1-3 .32 Safety come to mind. After those, the latch was (as you describe): in-line

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Mike Maher #283

I have owned many top-break S&Ws and never had a problem with any top latches, but I try to buy only solid lock-up, not abused guns. They have remained that way after all have been shot at the range many times over the years. The system must have been quite effective for S&W, since all Americans, Russians, Schofields, New Model 3s, 44 Double Actions, plus 32 Single Action, 38 Single Actions, 32 Double Actions, 38 Double Actions, 32 Safeties, 38 Safeties, 38 Perfected revolvers, and Single Shot Target pistols had top latches.

As for the types of locking mechanisms found on Safety revolvers, there are two different latches found on the 32, with the first being a push button rear latch that was changed out to a standard top latch around 1902. The 38 Safety had four changes made to the top latch over its production range. The first was called the "Z-Bar" which utilized were two different push button designs found on the sides of the top latch, there were also two types of push button latches on the 2nd & 3rd Models, and finally a standard top latch was adopted in 1898 with the 4th Model.

Can these latches fail, absolutely - but it takes deliberate abuse or over-pressure loads to break them in my opinion. Remember that these guns made the transition from black powder to smokeless with no changes in design, but when owners made that same change while reloading, the results could have been parts or gun failures. It was not an uncommon mistake to load early smokeless powders the same way as reloaders loaded cases with BP, fill the case with powder, leaving just enough room to seat the bullet. Obviously, if the gun did not blow up, parts would have been stressed beyond any normal limits.

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Gary
SWCA 2515

Thanks, that is exactly what I wanted to know, you guys are a great bunch.

Actually I think the top break latch mechanism is fairly strong. Look at heavy machinery chain. You can harness alot of horsepower with multi row chain. I once ran a drilling rig with 3 398 Cats (V12s) and they were linked together and to the draw works with machinery chain and that rig was rated to lift 1 million lbs. The pins on that roller chain were only about 1/4" in diameter, but 4 to 6 links wide depending on location. A top latch has 3 points similar to 2 link wide chain and even my little 32s use about a 1/8 pivot. My 44 Russian has a slightly larger pin, bigger posts and the "links are heavier. As long as the lock up is tight and in line it can take a pretty good load. Now slack in the lock up would cause a shock load and that is bad. But then look at the early Colt revolvers that had no top strap and just a wedge to hold the barrel to the frame.

Although I don't think something like a 44 mag or a 500 would work out with those sized latches I think one could be made. When revolvers blow up it is almost always the cylinder that lets go and takes out the top strap. I have never seen a top strap failure where the cylinder was intact. But, I suppose it has happened.

Look at the locking lugs on bolt action rifles they work square to each other

How may have seen a top break that had the latch fail?

Well I posted a photo of one in my original post and in fact most of the old break top guns if they have seen any use at all are lose, even .22's. Now admittedly I'm not talking Smith & Wesson but guns of lesser quality, still, latch failure is the number one problem with those guns.

".. but guns of lesser quality, still, latch failure is the number one problem with those guns." And they are not made by Smith & Wesson.. there might be a lesson to learn in there somewhere.

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Mike Maher #283

And they are all close to, or over 100 years old.

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No gold. Only lead. Bobby

I must admit that once again as a new member and new collector as in I haven't actually bought a top latch yet but have my eye on one you guys are truly amazing in your knowledge of revolvers and also engineering in general .We have gone from black powder loading to heavy machinery building in this one thred .You are an amazing group of people impressive.

Sorry if I ruffled some feathers here, didn't mean to butcher a sacred cow. MY point was that there are better designs, not that you can't limp along with a poor design.
In Ken Waters book of pet loads he lists some .38 S&W loads with the usual warning that they are not intended for small top break guns and adds this "and in saying this I don't have reference to only the cheaper makes either, having once seen the latch blown off a fine S&W Perfected Model in almost new condition." He goes on to say the British Webley and Enfield revolvers are safe. Having owned several Webley & Enfield revolvers both large and small I certainly don't consider them to be of S&W quality but even when the soft internals are worn out they still latch up tight, their design does not demand the finest metallurgy and workmanship to compensate for a poor design.

If I remember correctly, Ken Waters was an avid wildcatter and pushed the limits of many firearms, but he apparently does not know much about S&W Models. The Perfected was a double locking revolver that locked up like a solid I frame revolver. plus had a top-latch. The last top-break design introduced by S&W and saw a total production of almost 60,000 from 1909 to 1920.

The combination of a thumb release mechanism, (where the cylinder pin that travels through the cylinder and locks into a recess in the rear frame) as seen in all solid frame S&Ws plus a top-latch makes it just about impossible for the top latch to fail without the second locking mechanism breaking as well and more likely the gun blowing apart. Any standard loading would do nothing to this gun, so who knows what the situation was that Ken referenced. Maybe someone was wildcatting the 38 S&W?? I can reference failures in just about any firearm ever manufactured, including today's models, so vague references about failures, are not scientific evidence of the inadequacies of any particular design of any brand or model revolver. If you remain very concerned about top-latch revolvers, don't buy or shoot them.

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Gary
SWCA 2515

No ruffled feathers here; but I do like beef. I believe Smith & Wesson recognized the limits of their top break design and that research lead to their solid frame design; larger calibers, higher pressures driving faster loads, etc.. Still, there have been catastrophic failures in that design too. Was Ken Waters in the room?

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Mike Maher #283

The simple truth is that the early top break design was a product of the 1870's and were designed for Black powder use only. The introduction of smokeless powder brought on a lot of significant problems for the older guns. The older top breaks also had black powder rifling. Wide lands and grooves. Pressure spikes that exceeded their design would occur with smokeless powder use. The latch and catch were not engineered to sustain this type of abuse. Hense the damage. It is true that top latch models continued into the smokeless era but they were more often backed by the engineered addition of a side latch that became the standard after the 38 perfection model was discontinued. Lets also remember that these are aged firearms that have "seen the elephant" many times. Lets cut them a little slack.

The top-break S&W revolver was manufactured up to WWII and remained in S&W catalogs for almost the first half of the Twentieth Century with no mention of black powder being required. Almost all guns made the transition from black powder to smokeless without notice, by the early 1900s. There were no significant design changes made to these guns from pre-1899 days and ammunition companies still manufacture 32 S&W, 38 S&W, 44 Russian, 44-40, etc.

The 38 Perfected revolver was the only top-break to add the thumb latch and was not a popular gun, partly since it was competing with new solid frame revolvers that shot more powerful higher velocity ammunition than was available with previous models and calibers. Take a look around the Forum for many threads and posts with differing opinions, many backed by research, and experiences.

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Gary
SWCA 2515

My original post was intended just to discuss the variations in the latch arrangement. It seems that in 50 years of production they went through 5 different latches and , from an engineering perspective, it would appear that the earlier latches would be the stronger and more durable. It seems they never were happy with any of the latch arrangements but kept experimenting to the end.
My interest in the Safety Hammerless revolver in general was spiked by my recent acquisition of a couple of old books by Julian S. Hatcher and Elmer Keith. Both spoke favorably of the revolver for personal defense. Neither were especially thrilled with the "stopping power" of the .38 S&W cartridge, though both rated it much superior to the .380 ACP and both commented that it could be improved by hand loading with Keith's 160 grain semi-wadcutter bullet which was then (circa 1930) something new to the shooting world.
I have recently acquired a Safety Hammerless in what I believe to be the third variation and will post photos when it arrives.

I may be lucky, but I do not own any with movement and only a few with an audible clicking, but no perceptible play in the latch. I guess it is a normal metal wear issue in most cases, since some of these old top-breaks may have been opened and closed thousands of times.

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Gary
SWCA 2515

Well that is a function of the latch design. The rotary motion around the hinge pin starts out as mostly upward motion, then arching forward. That is why a latch designed to hold the top strap down against the frame, like the Webley, the Scofield and some of the other early S&Ws will remain tight while a latch designed to hold the top strap "back" against the standing breech will become lose after very little wear. It's like a chain across a door will always permit the door to open a certain amount versus a solid latch which can be fitted up quite tight and will stay tight.

Not quite on the topic at hand, but an old friend of mine used to mention that he worked summers, between college semesters, for William Crites who ran a gun shop in San Antonio, Texas in the late 1920s and early 1930s. He said that whenever top break revolvers were brought in for repair, the old man would wait until the customer exited the shop, open the revolver and rap it smartly against his work bench until the latch would lock tightly again and pronounce it "fixed."

Think of the evolution of the revolvers in USA. The Colt Walker, Dragoons, 1851 Navy and 1860 Army had NO top strap. The barrel held in solely by a tapered wedge and a line up pin.

Makes you wonder how much stress is actually placed on top strap and latch on the top breaks. Also, the frame / barrel assembly when fired with proper loads.

I've seen and handled many "well used" top break revolvers. Yes, the average, utilitarian or military use revolvers get loose and sloppy over time ... to a much lesser extent the Schofields.

Big mistake that S&W didn't want to pay the royalty to Gen. George Schofield to continue using the Schofield type latch / catch assembly.

However, a well cared for and maintained top break provides many years (to decades to now centuries) of faithful service albeit they have not been in daily use all that time.

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ANTIQUESMITHS
LM1300 SWHF425

That's very interesting about the topbreaks making it to WWII. I stand corrected. I could only find one in the model 5 hammerless 38 that made it to 1940. The perfected model sold almost 60,000. I'd say that rates for some popularity. My research of antique firearms transitioning to the new era of smokeless actually did see some form of change. Not necessarily to outward appearance but metallurgy and bore dynamics that must be mic'd to be understood. As an example, the .38 special was introduced and remains at .358. The original 38 S&W mic'd at .361. These changes were purposely done by the industry to protect the older guns when using smokeless powder to introduce lower pressures. I have not performed a bore study of the Smiths but this must have happened also or dangerous pressures would have been introduced to the older guns having black powder lands and grooves vs modern guns having narrow lands and grooves and reduced bore size. I would like to see a later model topbreak post 1900 and compare the bore rifling. Would be willing to bet that the rifling changed significantly. "Without Smith telling us about it". This to reduce pressure spikes from Smokeless powder use.

That's an interesting thought on the change of bullet diameter to afford a pressure reduction but I'm not sure it applies since the SAMMI specs for .38 S&W still specify a .361" bullet diameter and most other cartridges retain their original diameter.
One pressure reduction practice I have observed is with the typical "Saturday Night Special" revolvers by Harrington & Richardson, Iver Johnson and such. All of those I have examined have unthroated chambers, meaning the chamber is bored full case diameter straight through. If you remove the cylinder from one of those you'll find you can drop a cartridge into the front end as easily as the rear. That of course makes accuracy hopeless since the bullet has room to wobble through the oversize chamber to strike the forcing cone off center and crooked. But it no doubt also reduces chamber pressure by allowing powder gas to blow by past the bullet.

Yes Sir, I did not perform a study on the Smiths. There were additional methods used by manufacturers to reduce pressure. Changes to land(rifling design) was by far the most common. Black powder barrels having wide lands (for the most part) there are always exceptions. All of the top break Smiths that I have examined have the black powder lands. But my study on them isn't really a study at all but the old and most common "eye ball test". You would have to perform a bore dynamic comparison with the early models as compared to the later models. Also a close examination of the rifling. Bottom line is there "must be" a difference. It might be subtle but it's there. Maybe when I get a chance I'll slug a few late models and post my results in a few days. I do have a perfection model that dates to post 1900. I'll dig that one out and compare the bore dynamics to the earlier Black Powder era variations. At this point though based on research from other firms, I'd put money on there being a detectable and consistent change with my caliper.

I guess I don't understand why you say "there must be a difference". Most of our revolver cartridges and many rifle cartridges were originally loaded with black powder and smokeless powder loads were introduced for all of them. Even such outdated numbers as the .44 Henry rimfire were factory loaded with smokeless powder before finally being discontinued. Those smokeless loads were intended to be safe to use in the existing firearms of the day.
While smokeless powder certainly "can" produce higher pressures than black it does not have to do so. The ammo makers did much experimenting and testing before releasing new loads to the consumer. They made certain their ammo was compatible with existing firearms of the day, even if that meant settling for somewhat lower velocities than the full black powder load. Even today many factory loaded cartridges fall short of the velocities of the original black powder loads in order to assure pressures are safe in original firearms.

Sorry, but I believe you might be reaching for straws here. You will find no difference in the rifling between pre-1898 and post 1898 top breaks. Many top-break S&Ws were made well past 1900. 32 DA mfg. 1919; 32 Safety mfg. 1927, 38 DA mfg. 1911; 38 Safety mfg. 1940; 44 SA (NM3) mfg. 1913; 44 DA mfg. 1913. These revolvers remained the same design, same materials, and the same rifling. The only change was that the post 1900s guns shot smokeless and the pre-1900 guns shot BP, all without concern over the small differences in ballistics.

I checked my antique 38 Double Action revolvers and compared them to my collection of 38 Perfected revolvers to find no difference in rifling, twist/pitch, lands or grooves. Also, you will notice that I did not call the 38 top-break with a thumb release a "perfection", but rather by the name both the company and collectors call it.

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Gary
SWCA 2515

Ok, the wife went shopping so I managed to get some time in the shop. I pulled out the Perfected model and several earlier models.(Not perfection My fault: I was in the Utility business(explosive gas trainer) for 33 years and terms tend to co-mingle). I didn't eyeball the rifling but I did get out my multiple calipers and slugged 6 barrels in all. The land and groove design is visibly the same. But that's not what I'm trying to convey. The caliper is telling me that there is a difference between the earlier & late variations. I slugged and mic'd the models II and III.( I'm not hammering on my near mint model 1 thank you)..I also slugged and mic'd the perfected model. The earlier models have a .359 groove diameter. Matched on the model II and III's. With a land diameter of .353,.352,.352,.353, &.352. This variation is due to normal rifling wear. The Perfected model mic'd at .356 groove diameter with a bright and perfect bore having sharp but visibly shallow .354 rifling. This represents only a preliminary test. In order to perform a more accurate test I would have to slug and mic at least 20 of each variation. I would also like to slug the later models that date to 1940 or close to it. But this test not only suggests the bores are different but that the earlier variations had larger grooves and taller lands as compared to the grooves. You would also have to compare earlier black powder manufactured rounds, which we already know would mic at .361. To the later light loads of smokeless. Heeled vs hollow based? .361 vs. say .358/.357? I know, it's not a "HUGE" difference but it does in fact consistently register on a caliper and it was obviously done on purpose!
I also performed a "complete" and thorough test for the .41 caliber derringers of the black powder era. This was performed for a book that I wrote on the .41 rimfire short. "Huge difference" in Groove and Land Diameters. In fact that B.S. stigma associated with the Remington Double derringers being under powdered??? 400 FPS normal. That's wrong! There was a groove change on those that took place about 1896. I documented that in my book on 41's. It's obvious and yet nobody has bothered to mic the bores on them as well. They changed from .406 to .399!!! groove diameter at the turn of the century...Hense the smokeless era. The bullets also changed for the .41 rimfire from (.405-.411) to .401 in diameter at the same time. All this published info on the low velocity of the .41 is simply based on shooters using the "wrong" (Undersized ) bullet for the bore in question. This just further supports that the industry did in fact make changes to bore dynamics to protect the earlier guns from smokeless powder issues. That's all I'm saying fella's.

Remington bore change.jpg

Here is a photo from my book on .41's. You can see the bore change without a caliper. This took place during the industry's change to smokeless powder. About 1896.

I have to stop doing all these side jobs, since I am retired and have too many fun things to do. Measured about 15 guns, both sides of the 1898 date. I can find no correlation between antique and post-antique guns. Certainly nothing that a soft lead bullet cannot handle with little or no difference in pressures. As I mentioned before, no change is design or barrel rifling and diameter by what I am observing and I have never read any accounts of barrel changes made during or after the transition from BP to smokeless.

The chart below includes models, serial number ranges, measurements, and ship dates.

38 Perfected, 1st Model . . . . . . . . 8,XXX . . . .361 . . . .1912
38 Perfected, 1st Model . . . . . . . 38,XXX . . . .359 . . . .1913
38 Perfected, 2nd Model . . . . . . .57,XXX . . . .360 . . . .1919
38 DA, 3rd Model . . . . . . . . . . .222,XXX . . . .361 . . . .1889
38 DA, 4th Model . . . . . . . . . . .485,XXX . . . .362 . . . .1906
38 Single Action, 2nd Model . . . . 14,XXX . . . .362 . . . .1878
38 Safety, 2nd Model . . . . . . . . . 72,XXX . . . .361 . . . .1893
38 Safety, 3rd Model . . . . . . . . .115,XXX . . . .360 . . . .1902
38 Safety, 4th Model . . . . . . . . .200,XXX . . . .360 . . . .1906
32 Single Action . . . . . . . . . . . . .56,XXX . . . .312 . . . .1871
32 Safety, 1st Model . . . . . . . . . . .4.6XX . . . .312 . . . .1889
32 Safety, 2nd Model . . . . . . . . 217,XXX . . . .312 . . . .1920
32 DA, 2nd Model . . . . . . . . . . . .20,XXX . . . .311 . . . .1881
32 DA, 4th Model . . . . . . . . . . . 247,XXX . . . .310 . . . .1905
32 DA, 5th Model . . . . . . . . . . . 272,XXX . . . .311 . . . .1905

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Gary
SWCA 2515

I know that early 41 RF, and many other RF and centerfire cartridges, used heeled bullets, meaning that the bullet was the same size as he outside dimensions of the case. Later designs inserted the lube rings into the case, making the bullet smaller, while still being able to use the same size casings. This allowed the use of the modern ammo in older guns, since the chambers did not have to be altered. It is also reasonable that the new guns would reduce the bore diameter to accommodate for the smaller bullets. I do not believe that it had much to do with smokeless powder, but rather there was much criticism about outside lubed bullets picking up dirt and debris and losing their lubricity over time. References have been made that the Russians facilitated the change from the 44 American (heeled bullet) to the 44 Russian (internal lubed bullet) caliberr for that very reason.

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Gary
SWCA 2515

BMur, sir, I think you are confused in regard to the transition from black to smokeless powders. It was not necessary to adapt the guns to lower the pressure of the new powder since ammo makers loaded the new powder to pressure levels safe in the existing guns. It would serve no purpose to adapt new firearms for smokeless powder when those smokeless loads would still be fired in the old black powder guns, such as we are still doing today.
Your measurements show the newest revolver having a groove diameter of .356". Now how is that going to reduce pressure when the SAMMI standard bullet diameter remains a .361"?
I know nothing about the .41 rimfire except that being a rimfire the shooter has no choice but to shoot the bullets the ammo maker provides, there is no option of matching bullet to bore.

Hey Fellas, Please be patient. I don't know how Gary performed his research so fast. I'm not that fast. I'm in the process of pulling bullets from the black powder era 38 S&W's vs. smokeless and will present my findings as soon as I can.
As far as the .41 rimfire. I don't need to perform any more research for that round or the history there of. The .41 rim fire was introduced with the .41 Moores derringer in 1861. (Not 1863 as found on the internet). The first variation was actually a centerfire and introduced in late 1860. Found to be defective the Moores firm converted the model's 1 & 2 to .41 rimfire because that was a more reliable cartridge primer at that time in history. I performed close examinations of over 60 single shot and double shot .41 derringers and found a huge variance in groove and land diameter of early production derringers. The reason for this was "Black powder use" and also the fact that the firms were in no way standardized. In other words they did what ever they wanted without uniformity. They simply hired out a specific firm. Example: Remington hired out Union Metalic Cartridge Co. to engineer a special cartridge/bullet for their needs. Other firearms firms did the same for their specific firearm designs. The result was chaos with bullets, powder loads, case lengths, and bore dynamics. The only reason they got way with this was with the use of Black powder.
With the introduction of semi-smokeless powder in the early 1890s you will notice specific changes that took place with bullet types. Outside lubricated bullets now eliminated in favor of inside lubricated "Hollow based" bullets. Gary mentioned only one reason for this. Dirt getting on the lubricated bullet. But in reality the bullets were grossly undersized for both the 38L cal and 41L cal. They relied on expansion of the hollow base to seal the bore. This design did also reduce pressure.
With the 41 rimfire the industry decided to reduce bore dynamics and bullet size of the modern derringers. Primarily with the Remingtons since that variation was one of the only surviving examples to make it into the smokeless era. This bore reduction and bullet reduction to solve the same problem. Pressure!! Remember, This is 1898, not 2017. They did not have the plethora of smokeless powder types that we are fortunate to have today. The smaller bullet would still function in the older guns but the performance would be reduced considerably. The industry didn't care about that! All they cared about was safety and liability with the older guns. So if you shoot a smokeless round through an older Remington derringer it will function safely but the performance will be reduced considerably. The post 1898 derringers, That I posted a photo for all to see! has a smaller bore that is engineered for the undersized smokeless round and will produce significantly higher velocities since it has the correct size bore. They are .399 groove with the standard and post 1900 .401 bullet. I can't make that any clearer. I documented this change. My data is accurate.

What I'm working on now since I mentioned early on that I did not conduct a study on the Smiths, is a close examination of the bullets. I'm going to present photos of bullets, powder, cases, etc when I'm through with my study. Please be patient.

Ok Fellas, I decided to perform manual reference research prior to a bullet/cartridge inspection. I'm glad I did. Over and over again in my early loading manuals they list a bullet change for the original 38S&W from .361 to .358/.357. My loading reference is from the following manuals.
Ideal volume/circa;
5 1892
6 1894
8 1895
10 1898
17, 26,32,34,36,37,38,39,41 through 45, Lyman cast bullets reference circa 1955

Speer 1,3,6,7 &10....Very interesting reference to the early 38 S&W and I quote: The following loads listed are intended for and should be used only in modern solid framed revolvers. For safety sake, all hinged frame revolvers made prior to WWII should be placed in honored retirement. The 38 S&W sees little use and is fast fading into retirement. (just like us)

All of the listed loading references depict a ".358" bullet change from the original .361 bullet. This includes bullet molds post 1900! 358 being the first 3 numbers on the mold. Identical bullet design but a smaller diameter bullet. I also mic'd an original lead bullet from an ideal loader from the 1880's and found the original bullet was in fact .361. Right at the beginnings of the smokeless era for some reason the bullet was reduced to .358/.357.
Simple truth: The original .361 bullet was reduced in size to .358/.357 in the 1890's with the introduction of the semi-smokeless era. I can pull modern loads to further the point but it seems mute to me at this stage.
As far at groove diameter changes. Later variations would almost certainly have groove diameter changes with metallurgy improvements to match the .358 bullet. My Perfected model is a late serial number and mic'd at .356....That also makes sense. I would be interested in examining the latest variations that date to 1940 but I think I already know what results would be at this point.

SAMMI cartridge specification as of present time.

Attached Images

38 S&W.jpg (68.4 KB, 24 views)

Very cool drawing. You will notice at the base of the head an obvious taper on the brass shell(The bottom)? This is symbolic of a "balloon head" case. In other words, a black powder case. Ballon head cases had a deeper inner shell that surrounded a large primer pocket that stood up inside the case. Looking like a small tower inside the case. Shall I post a more modern smokeless diagram? As seen in all of my reloading manuals except for the very early antique manuals? I wonder if you might also post the written info on the page and where you obtained this drawing please.
The modern drawing will depict a "solid head" case. These cases have a squared off rim with a line above it milled into the case. Like a .38 special case. Also, if you look inside the case you will see a flat area at the base with a small primer hole. The Solid head case has been used basically since the beginning of the smokeless era. Modern cases also have no taper on the base of the head. They are designed for more pressure. The pressure you would see with smokeless loads. I collect cartridges also. They are really getting pricey. Especially the older ones like the example in your drawing.

It's a drawing, not a photograph, none of the revolver case drawings show a groove ahead of the rim, that is shown only on auto pistol cartridges. Even such as the .41 magnum which certainly was never loaded in balloon head cases. It is the current specification for the cartridge, visit the SAAMI site and see for yourself, I'm surprised you didn't go there already.
Bad Request

ANS-SAAMI is a voluntary reference that was first established in 1979. The drawing on the 2015 website does not in anyway look like the photo of the drawing that you posted. They reference a maximum bullet diameter of .3610 with a tolerance of .0060 deviation. You can see the same reference with the .38 special. .360 with a tolerance of .003. Also the old 45 Colt they list with a bullet diameter of .456. That diameter is the "OLD" bullet as I have shot the 45 Colt many times in the SAA. Modern bores are 452-454.
Assuming that you reload for the .38 S&W I'd also like to know where you got your .361 bullet mold? If it's not too much trouble. I looked at my reloading log and found that I used a 105 grain SWC pure lead .358 bullet and saw excellent pattern shooting at 15 yards with a model 3 DA TB. Using Black powder. I also used a 148grain WC .358 bullet and saw very similar results. The only option that I am aware of for the .361 bullet is the antique Ideal field loader or the target 38/44 of later manufacture.

Where did you see me reference your "Drawing" as a photo?

I said "Drawing not photo" because a specification drawing shows only dimensions which are specified. SAAMI does not specify an extraction groove ahead of the rim of any revolver cartridge. Whether or not you like it that is the current specification for .38 S&W cartridge.
The bore of my .38 S&W mikes .361" groove diameter as nearly as I can measure a 5 groove slug. When I start to reload I will first try .358" bullets because I already have a bunch of them. If I feel the need for .361" bullets I can get them here:
ttps://www.grafs.com/retail/catalog/product/productId/21168
Or here:
.361" 145 Grain Round Nose Hand Cast Soft Lead Bullet 20-1 Alloy SPG Lube Bullet Box of 50 - Buffalo Arms
Or I can get the .360" bullets Magtech currently produces for their factory loads from here:
Magtech Bullets 38 S&W (360 Diameter) 146 Grain Lead - MPN: BU38SWA
Ain't the internet a wonderful thing?

Thanks for the info on the cast bullets. I did ask for available molds? I will get to work right away on correcting all of my manuals from 1892 - present day and correct them to circa 1979 Sammi "The Bible" of loading standards. God Bless The internet!

3 bullets ref 1955.jpg

3 band bullet.jpg

1898 Ideal ref.jpg

Here are but 3 references for the .358 bullet associated with the original .38 S&W. I apologized that they are not Sammi references but they do pre-date Sammi by 80 years! The written section is from an 1898 loading manual that specifies the .358 bullet for all S&W's. Also later 1936 ref for the earlier two band bullet. All of which are .358. then of course the standard 3 band bullet from a 1955 reference, which is also .358. I guess these guys all got it wrong too. I don't know, but these also are references for existing antique bullet molds if you are interested in obtaining one. I think my interest in this thread has now exhausted. Thanks for the interesting info.

Interesting, actually the drawing I posted is from the Lyman Handbook 49th edition, which is the most recent. For some reason, likely my lack of technological expertise, I was not able to copy the drawing directly from the SAAMI site but the Lyman drawing was identical. My earlier Lyman books show no specifications but only say "a wide variation in groove diameter exists among handguns chambered for this cartridge so the user is advised to slug his barrel and load bullets .001" over groove diameter if possible". Which is exactly why SAAMI was created.
Most bullet molds do cast at least .001" and up to .005" over their designated size so I would not be surprised to get .361" bullets from a mold labeled 358. I have no intention of casting for this little pocket pistol since I doubt I'll be doing a lot of plinking with it. One option I did employ with a British Enfield revolver with .361" bore was the use of .358" 148 grain hollow base wadcutter bullets, accuracy was not match grade but I didn't expect that from an old military revolver.

This thread has drifted pretty far from it's original question and has run on and on in circles so I suggest we just agree to disagree and let it go.

I am afraid that you are looking for information to support an answer you already have. Usually, it is the other way round?? I also guess you did not notice that I had measured three 38 Perfected revolvers and they all came up with the same nominal groove diameter as their predecessors. I have one of the latest 38 Perfected revolvers made and it was made in the last year of production They all used exactly the same barrel assembly as the original 38 DAs and the frame was adapted from a Model 1903, 32 HE, I frame. Bore dimensions of the 38 top-breaks did not change period!! The mouth of the cylinders will measure about .361" and so will the grooves if care is taken to make sure you are not measuring the lands.

There is data that shows that 38 Colt, not S&W 38 Special underwent a size reduction from .377 to .357 around 1900. The 38 Special was designed from the start to use .357" bullets, never .361" of the 38 S&W or 377" of the 38 Colt. There is evidence that the size reduction of the 38 Colt bullet was a result of the Army and Navy purchasing S&W 38 Special revolvers and both Colt and S&W hand ejectors needed to be able to use the same ammunition. Around the turn of the Twentieth Century, these calibers were also called 38 Military and 38 S&W Special & US Service cartridge for a time In the Model 3 & N frame revolvers, the first was 44 Russian, which evolved to the 44 Special and ultimately the 44 Magnum. Today's 44 Magnum revolvers will shoot all three cartridges, which are still to this day .429” diameter bullets.

No reloading die sets made today offer a smaller bullet cartridge for smokeless powder era versus a larger bullet cartridge for BP era. No reloading data offers a smaller post-BP bullet for reloading those calibers of the late 1800s. As for 45 Colt, it is true that Colt changed the size of their bullets, but it happened in 1891, not 1900. Frankford Arsenal loads in January, 1891 used a .453" bullet and maybe by coincidence, that same date is when the arsenal went from copper to brass casings. I see that there appears to be no way to pull you off the path that you believe that all smokeless caliber bullets were reduced in size from their BP predecessors to effect a lower pressure load, no matter what information and data we provide, so I also give up.

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Gary
SWCA 2515