Pietta black powder revolver tested for hardness.

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Hasaf said:
I had always understood that the reason for shooting pure lead only was the relatively poor quality steel used in reproductions and available historically.
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I thought jacketed bullets are never used with black powder due to the different pressure curve of black powder... where it would spike from the added resistance of initially squishing the jacket into the rifling, compared to just soft lead.
 
hrt4me said:
so no modern parts fit those classic Santa Barbara New Army Model '1858' revolvers?
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Not likely but I've never seen the inside of one. Being made in Spain I think it's highly unlikely any Italian parts could be made to fit.


LaneP said:
Just an anecdote to this thread, but in the late 80's, I cast some RB's that were alloyed with tin (big mistake). A friend and I went to the range with these projectiles and some Pyrodex P. He brought his Euroarms Rogers and Spencer and I had a Lyman (Armi San Paolo) NMA .44.

After 6 shots, my revolver went out of time and the cylinder wouldn't lock up. I stopped to get a closer look and the frame had stretched forward enough to open the b/c gap to at least an 1/8th inch. We looked over his R&S and he didn't have any such stretching but his forcing cone was cracked.

I've never used Pyrodex or alloyed lead since. I don't even remember why I did that, but probably was left over from casting .44 Mag SWC's. Those repro's are soft, and that was an object lesson.
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Was your frame brass? I have used clip on wheel weights and broke a Remington loading lever trying to seat them. I have used .452 SWC's made with hard lead but loaded them off the frame with no problems.
 
hawg said:
Not likely but I've never seen the inside of one. Being made in Spain I think it's highly unlikely any Italian parts could be made to fit.




Was your frame brass? I have used clip on wheel weights and broke a Remington loading lever trying to seat them. I have used .452 SWC's made with hard lead but loaded them off the frame with no problems.
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No, wasn't a brasser. IIRC they were .454's and seemed to seat normally that I recall. That combination also had heavier recoil than normal also.
 
hawg said:
I would think they're the same and relatively soft at that. Yes they're good enough for very heavy use. I just don't believe 3F cracked forcing cones in original revolvers.
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Particularly since the cartridges of the time may have used 4f powders…
 
Johnm1 said:
I wish I understood pressure and the units. In that chart is LUP lead units of pressure? I think there is CUP or copper units of pressure but never heard of LUP. As I understand it there is no conversion from CUP to PSI.
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It is indeed lead units. That same manual shows a pressure decrease from 3 to 4f powder in the case of G-O powder. An increase in pressure in the case of C&H. C&H powder in either granulation gave lower pressure than either of the G-O powders tested…
 
woodnbow said:
It is indeed lead units. That same manual shows a pressure decrease from 3 to 4f powder in the case of G-O powder. An increase in pressure in the case of C&H. C&H powder in either granulation gave lower pressure than either of the G-O powders tested…
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The below article does a good job of explaining CUP and PSI and why there isnt a direct correlation between the two units. It doesn't address lead units of pressure but I assume the method of measuring LUP is similar CUP just using a different media.


https://www.shootingtimes.com/editorial/ammunition_st_cuppsireloaddata_200905/100105
 
And the OP does a fantastic job of explaining how REALLY SOFT the steel on these replicas are.

The internals such as the trigger and hammer are also really soft steel with a surface hardening which is something to be aware of if doing a trigger job. They have to have the surface hardened again after the work.

The mild (as in zero to almost zero rockwell) steel used today may be more impurity free and better overall than 19th century steel (???? can a good blacksmith even the odds ???) but it's still soft steel only good for black powder type pressures just like the good old days.

Modern ordinance grade steel like that used in smokeless powder guns or anything like it is NOT USED in these replicas and it's important to make that fact crystal clear for safety.

Logic tells me shooting hard lead is going to wear the soft steel barrel out faster, how much faster and whether it's significantly faster is a matter of debate certainly dependent on how many times it's fired. My opinion is if you want to treat these things good use only soft lead.
 
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grter said:
The mild (as in zero to almost zero rockwell) steel used today may be more impurity free and better overall than 19th century steel (???? can a good blacksmith even the odds ???) but it's still soft steel only good for black powder type pressures just like the good old days.

Modern ordinance grade steel like that used in smokeless powder guns or anything like it is NOT USED in these replicas and it's important to make that fact crystal clear for safety.
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As best as I can tell, Colt didn’t start using steel until the 1860 Army revolver. There are some stories (maybe not all are reputable, but there are enough accounts to convince me that at least some are true) of early cylinders failing. A good blacksmith (should he have been so engaged) would not be able to even the odds, because he would still be working with iron. Our mild steel repros are at least better than that. By a long shot. (I’m not advocating trying to make your Italian BP repro into a .44 magnum though!)
 
"From my experience and the results I can confidently say that the screw was made of unhardened mild steel as it didn't register at all, at the RC scale."
My tests of 1018 usually show 15-18 Rc. If your tests showed less than that it may be that the sample was "unloading" as perhaps when testing a tube. Anything that allows the sample to move away from the diamond's pressure will show less hardness, a big hole in the center of a tube will allow considerable movement unless that bore is well and solidly plugged so that the walls cannot "egg" away.
A friend of mine once told me he was in a US factory that made BP rifle barrels and they were using 12L14 steel, also known as "Laled", and that it was left in the annealed state. This didn't surprise me at all. 12L14 comes very soft.

Other than that I did see an ad in a gun magazine once that said their shotgun barrel was made of 4140 steel, but it didn't say whether or not it was hardened afterwards.

I thought I may have seen implications here that Italian BP gun makers use crappy steel, that would surprise the heck out of me since Italy has been a leading nation for gun manufacturing for hundreds of years, and I doubt they'd like to see such statements in a firearms forum.

On the other hand engineers tend to try to satisfy both a safety factor and a cost factor, of which the safety factor normally carries more importance, so if 1018 met both that would probably be what they'd call out for both. (Though a free machining steel like 12L14 should, I think, be better for cost even though more expensive as it saves valuable time).

I'd be more impressed by the test findings if you had tested both a BP barrel and a similar wall thickness .44 octagon or hex smokeless barrel plugged and tested and they differed (I'd love to see that), but America, being excessively litigious, may require manufacturers to operate from a higher safety factor with thicker walls or alloy steel like 4140 (Just speculating).
parts
 
The Centaure New Model Army as well as the Santa Barbara New Model Army are made of high quality steel, which was also reflected in the price. See analysis report on my homepage. In the beginning, the Italians manufactured with less alloyed materials. Sometimes it was life-threatening to shoot with it. Fortunately, that has changed until today.
 
"Colt didn’t start using steel until the 1860 Army revolver."
I too have read several times that both the Patterson and the Walker were made of wrought iron. Wrought iron is far weaker than low carbon steel because it has slag inclusions that make very effective stress risers, I don't doubt the exploding cylinders stories in the least, a Walker made today in Italy is not likely to explode unless there's a bullet lodged in the barrel or someone pours smokeless in them.
 
HisSoldier said:
"Colt didn’t start using steel until the 1860 Army revolver."
I too have read several times that both the Patterson and the Walker were made of wrought iron. Wrought iron is far weaker than low carbon steel because it has slag inclusions that make very effective stress risers, I don't doubt the exploding cylinders stories in the least, a Walker made today in Italy is not likely to explode unless there's a bullet lodged in the barrel or someone pours smokeless in them.
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Colt used steel for barrels and cylinders starting in 1860. They used wrought iron for frames up until the smokeless era.
 
Ok, guys. I promised you to test an Uberti barrel next so here I am.
My local gunsmith finally obtained a piece of Uberti barrel that he could give me for a few bucks. Actually the story behind this piece is quite interesting. It was harvested from a Uberti revolver that came from factory with a whopping 0.04" cylinder gap. The guy who bought it wanted to correct the gap himself but managed to only damage the end of the barrel while trying to unscrew it. The steel was so soft that it would rather indent in a vice than start unscrewing. Long story short, the gunsmith had to make a custom wooden clamp and his magic to finally be able to remove the barrel from the frame. Then he cut off the damaged end of the barrel and boy, it cut like butter. He held Heritage to low standards but after dealing with italian black powder makers Uberti and Pietta, he had to change his perspective a bit.

At this point I was quite sure this steel will be soft as mush but I contacted a machinist to test it anyways.

He was no able to get a reading on the RC scale. Given the already poor record of this piece, we agreed that this steel is simply so soft it will not record on the RC scale.

I have no information (apart from the fact that he tried putting it in some kind of a vice) how exactly the previous owner tried to unscrew the barrel but he managed to botch the barrel pretty good. You can see for yourself here:
upload_2022-2-18_18-32-12.jpeg
 
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Thousands of these reproduction guns are shot by folks every year but I don't remember hearing of any that are blowing up on firing. So they must be strong enough for normal use. Even the dreaded brass framed guns will give decent service life if they aren't pushed too hard. And yes I suppose they can be damaged by trying to ram oversized/extra hard balls into the cylinder. You might bend the rammer or the rammer pivot screw. But thats easy to replace and you will learn a lesson about what lead you use to cast your balls with. Or just stick to factory made round balls and you should be fine.
 
Captain*kirk said:
[...]speaks loud and clear (to me) to the practice of loading smokeless loads for conversion cylinders...doesn't matter if the cylinder is proofed for factory .45LC ammo...the barrel is clearly NOT.
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This brought a thought to mind. Does anyone know if there is a meaningful difference between smokeless and black powder pressure by the time the bullet/ball leaves the cylinder?

My hypothesis is that the softer barrel steel could be damaged more by the harder bullets (particularly jacketed, although hard cast bullets are typically much harder than balls sold for bp revolvers) than the pressure. Just a hypothesis though.

Does anyone know if the failure mode of a converted bp revolver is the barrel bursting, flame cutting the top strap (where present), the rifling tearing out, the frame stretching, or the cylinder pin hole egging out? Does anyone have pics, even if they came from some unreliable source? Even if it was a gross overload that blew up a conversion cylinder it would be interesting to see how it failed.
 
Also a fun fact is that Italians themselves sometimes have issues because of their steel selections while screwing in the barrel.

A friend of mine bought recently pietta 1858 snub nose 'the Ace' with a twisted octagon barrel.
We are quite puzzled what exactly the Italians did here to completely disrupt the barrel geometry:

upload_2022-2-19_1-37-6.jpeg

My theory is that due to the snub nose barrel being much shorter, the leverage is much less and greater force needs to be used while screwing in the barrel which combined with the soft steel deforms the barrel octagon. Your thoughts?
 
Mauser lover said:
Does anyone know if the failure mode of a converted bp revolver is the barrel bursting, flame cutting the top strap (where present), the rifling tearing out, the frame stretching, or the cylinder pin hole egging out? Does anyone have pics, even if they came from some unreliable source? Even if it was a gross overload that blew up a conversion cylinder it would be interesting to see how it failed.
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This was posted on one of the forums about 10 years ago. I don't remember the details but it must have been a substantial overload.

Y3eTin9l.jpg
 
Mauser lover said:
This brought a thought to mind. Does anyone know if there is a meaningful difference between smokeless and black powder pressure by the time the bullet/ball leaves the cylinder?

My hypothesis is that the softer barrel steel could be damaged more by the harder bullets (particularly jacketed, although hard cast bullets are typically much harder than balls sold for bp revolvers) than the pressure. Just a hypothesis though.

Does anyone know if the failure mode of a converted bp revolver is the barrel bursting, flame cutting the top strap (where present), the rifling tearing out, the frame stretching, or the cylinder pin hole egging out? Does anyone have pics, even if they came from some unreliable source? Even if it was a gross overload that blew up a conversion cylinder it would be interesting to see how it failed.
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There was an interesting thread on a twin forum, 1858remington few years ago. Basically the .44 cal 1858 remington is a very poor choice to convert because of how thin the cylinder walls are and even minor overload might result in a catastrophic failure. upload_2022-2-19_1-48-56.png

If you want to read a full thread: https://1858remington.com/index.php?topic=2435.0

Obviously I mean 6 shot variants. The 5 shot one is much sturdier and the cylinder wall thickness is adequate in my opinion. But my stance on this topic, after consulting with the gunsmith and machinist, is to never use any kind of smokeless powder in those. As a matter of fact, I intend to keep them only in their percussion configuration.

So hawg showed you an exploded gated conversion and the thread above is the drop in conversion. Both failed pretty much the same way.
 
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My understanding was those conversion cylinders are heat treated to modern pressure standards (if wrong, apologies in advance), so whatever took that cylinder apart was certainly well overloaded. I know people regularly and safely shoot "cowboy" level smokeless charges in these guns but I have stopped the practice myself and use only BP and pure lead. Mainly just to reduce wear and tear if nothing else.
 
The major difference which is often overlooked is pressure spikes, which can be much more abrupt and violent in a smokeless load exhibiting the same approximate muzzle velocities. While the lion's share of the pressure is contained in the cylinder with some escaping past the cylinder gap, there is still a good amount left to be burned and expended within the barrel. Simply aligning equal muzzle velocities is not a valid pressure comparison, which can only be measured with appropriate pressure barrels, assuming they are is the same as saying all smokeless powders burn the same.
 
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