Turnover/revolving black powder guns

[Railstar]

Originally Posted by Fred Brackin

This you can stop worrying about. All revolvers (except he Nagant) have a gap between the barrel and the cylinder. It is known as the "barrel-cylinder gap" in technical jargon.

Thus all revolvers do lose a little bit but it's just not enough to matter. Probably not even if lower quality workmanship increases the size of the B-C gap. It's very likely to be an insignificant problem compared to the cruddy powder used in the historical matchlock period.

Thanks! This is useful. That takes that worry off the list.

Originally Posted by The Colonel

IIRC all powder based locks had a problem with priming in revolvers - the loose powder was prone to leak out of the lock.

And as previously noted, poor obturation (breech sealing) leading to multiple barrels firing at once was also a problem. This may result in additional balls heading towards the enemy, but it may also result in parts of the action heading for your face and the weapon coming to pieces.

Neither of these were undefeatable, but the cost made them very much curios rather than anything that could be reliably series produced - it was the percussion cap that really started to make revolvers feasible as you then had non-spillable spark stable priming.

That's interesting. I did some looking up this first, and while I know wikipedia is a limited source, the thing I found was chainfires were considered far less dangerous on pepperbox or turnover guns than on single barrel revolvers, because each bullet could still exit from it's own barrel rather than with a revolver cylinder with a higher chance of an explosive malfunction.

Originally Posted by sir_pudding

Quite a bit, since you now need precision machined parts with critical tolerances that mean the gun explodes if you miss them. You also are increasing material requirements by each chamber or barrel, in an era were steel quality depended on the crasftman making the thing.

(snip)

Turnovers nearly multiply weight and more than multiply cost by each barrel, which makes them unsuited to longarms (and makes them compete with simply carrying more pistols).

Really good points. Tolerances would be especially applicable to the setting - because one aspect of why gunpowder weapons didn't start to dominate the same way is because the local mana level could influence the power of gunpowder, either up or down depending on how fire-aspected the mana is... making it difficult to predict exactly how powerful a given gunpowder charge would be. So anything which needs fine-tuning of the tolerances would be considered extra risky because the explosive force can vary that much.

Essentially I'm thinking that factor would have caused energy-source based tech development to slow down behind mechanical tech.

Carrying more pistols is an especially good point too. If I work from +1 CF & +50% weight per extra shot, piercing size one step smaller, Bulk & Malfunction being 1 point worse (2 points worse for enough extra shots), and still needing to Ready the weapon between shots... I can see multiple pistols still being used by a lot of people.

[ericthered]

Originally Posted by malloyd

Really good machining makes both of these less of a problem - the parts fit better, so there is less leakage, and you can build a mechanical action that is accurate enough to align the chamber reliably - but good machining is *expensive* until the 19th century. Once the price falls you do start to see stuff like this (the first commercial revolvers were after all loose powder designs), but there's only about a 50 year gap between affordable machine tools and cartridges.

Quoted for truth. The revolver, cartridges, repeating riffles, and ultimately the machine gun, were all made possible by cheaper machining. Smokeless powder helped a little, but really the difference was machining, not gunpowder technology.

Early firearms were nice not because they were great weapons, but because they were cheaper than crossbows, had great armor penetration, and were easy to train peasants to use.

[The Colonel]

Originally Posted by Railstar

That's interesting. I did some looking up this first, and while I know wikipedia is a limited source, the thing I found was chainfires were considered far less dangerous on pepperbox or turnover guns than on single barrel revolvers, because each bullet could still exit from it's own barrel rather than with a revolver cylinder with a higher chance of an explosive malfunction.

Less dangerous, certainly. Still not a barrel of laughs.

[Polydamas]

Originally Posted by ericthered

Quoted for truth. The revolver, cartridges, repeating riffles, and ultimately the machine gun, were all made possible by cheaper machining.

It was also important that the percussion cap had been invented, so locks did not have to worry about loose powder and striking fire on the outside of the gun. Like The Colonel said, locks based on igniting a small charge of powder to ignite the big one pose practical problems in a repeating weapon.

Plenty of people make revolvers with hand tools and simple gauges, but primers (and later on cartridge cases and smokeless powder) are harder.

[fredtheobviouspseudonym]

the "harmonica" gun.

Apparently Jonathan Browning, the father of well-known gun designer John Moses Browning, made a few of these.

Basically you have a rectangular block in which there are several (3 to 5, usually) parallel chambers. To use, each is loaded and the block put into a slot in the weapon's receiver. After each shot that block is moved sideways to set another loaded chamber in line with the barrel.

For fantasy campaigns with firearms I let the dwarves use this as an option. It requires extremely precise shaping and fitting, and dwarves have a higher percentage of experts in these skills.

Each block would have to be painstakingly hand-fitted to each weapon. So, until the arrival of very precise machine tools, such weapons would be rare.

However. If you do have such a weapon & several blocks for cartridges each, you could put out 12-20 or more rounds in a very short time.