How does a revolver work with pressure and that gap in the barrel?
- Thread starter Lavid2002
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The escaping gas is a good reason to keep your support hand away from the barrel-cylinder gap. There's a YouTube video showing what happens to a hot dog in close proximity to the gap of a .500 S&W revolver. Ugh. Revolving rifles have never been popular because of that danger.
The pressure can be so high, as with the .357 Maximum, that unless special provisions are made, the hot gas will begin to erode the top strap.
THe escaping gas is also the reaon that silenced revolvers are not possible, despite what you see in the movies.
Regards,
Walt
The pressure can be so high, as with the .357 Maximum, that unless special provisions are made, the hot gas will begin to erode the top strap.
THe escaping gas is also the reaon that silenced revolvers are not possible, despite what you see in the movies.
Regards,
Walt
The effect of that escaping gas is also why you see the term "vented barrel" pertaining to ammunition manufacturers' performance claims. They "vent" the barrel in order to emulate the gas loss that happens in a revolver.
For the most part that is true, but I can think of 1 exception to that rule, right off hand. There were silenced Nagant revolvers. But then again, the Nagants were a strange bird -- they employ a curious locking design that provides a gas seal which makes silencers possible.
If the idea of a revolving rifle intriques you, you might still be able to get one. A replica gun maker, I think Uberti, was making a Remington revolving rifle. Looked like one of their .44 cal black powder revolvers, but much longer barrel and a crescent butt shoulder stock instead of a pistol grip. Fancy brass handguard too. And ajustable rifle sights. A few years ago at a gunshow I came that close to getting one. Someone had a used on for sale, it appeared new and unfired though. The price was a steal compared to the retail price but I drug my feet and someone else bagged it. Sellers that don't deal in BP arms sometimes come by them in trade ins and often sell them under value to get rid of them so that is worth watching for if into that. Anyway, in a revolver, the bullet does gain some fair MV before it is passed the gap and the gas can escape, try shooting a round from a revolver with no barrel, just cylinder. If it hits someone it might kill them! At very close range.
There was a picture floating around of someone who had their hand too close to the cylinder gap of a .460 S&W, yea, his thumb was nice and mangled up.
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Some folks suggest that people with weak index fingers pull a revolver trigger with the middle finger, leaving the index finger laying alongside the frame. I suspect they have not tried this themselves with a loaded gun.
I demonstrate the danger for the newbies by using a doubled piece of paper held over the gun. The shredded paper leaves no doubt that the gas escape from the barrel-cylinder gap can be dangerous.
Jim
I demonstrate the danger for the newbies by using a doubled piece of paper held over the gun. The shredded paper leaves no doubt that the gas escape from the barrel-cylinder gap can be dangerous.
Jim
bluetopper
New member
True, some gas is lost in a revolver, but my 6'' 45acp rev. still has more velocity than my 1911.
I was surprised myself.
I was surprised myself.
sw_florida
Moderator
To be precise, it's the particles in the high-pressure gas, particles moving very fast, that wears on the metal of the top strap. Until looking at the posted picture I wasn't aware of the amount of damage that can be done that way.
Swampghost
New member
As revolvers wear they can also 'cut lead' when the cylinder doesn't line up perfectly with the barrel.
I was at the range one day when the cop next to me was spitting lead THROUGH the divider. That indoor range is also a gunshop, I suggested that he have his pistol looked over.
I was at the range one day when the cop next to me was spitting lead THROUGH the divider. That indoor range is also a gunshop, I suggested that he have his pistol looked over.
carguychris
New member
As a related story, the Nagant revolver adopted in 1895 by the Russian Empire (and later used by the Soviets all the way through WWII) had a novel mechanism that cammed the cylinder forwards when the trigger was pulled, eliminating the forcing-cone-to-cylinder gap.
However, this mechanism adds mechanical complexity to the gun and gives it a very heavy trigger pull (like 20+ lbs DA).
The idea has generally been regarded as pointless because IIRC testing has shown that eliminating the gap only improves velocity by ~50 fps or less. The Nagant 1895 was the only revolver ever produced with this mechanism and that should tell you something.
HOWEVER...
The Nagant 1895 is the only revolver that can be used with a suppressor! They won't work with conventional revolvers because they only eliminate the "bang" coming out of the barrel... they can't prevent the "bang" coming out of the cylinder gap.
However, this mechanism adds mechanical complexity to the gun and gives it a very heavy trigger pull (like 20+ lbs DA).
The idea has generally been regarded as pointless because IIRC testing has shown that eliminating the gap only improves velocity by ~50 fps or less. The Nagant 1895 was the only revolver ever produced with this mechanism and that should tell you something. HOWEVER...
The Nagant 1895 is the only revolver that can be used with a suppressor!
They won't work with conventional revolvers because they only eliminate the "bang" coming out of the barrel... they can't prevent the "bang" coming out of the cylinder gap.Lavid2002 - even though the pressures involved are very high, when you do the math you'll find that the area of the gap is very small. For a nominal .005" gap in a .357 Magnum for example, the actual area of the gap is only about .009 sq. in. That translates to very little pressure bleeding from the gap when compared to the pressure on the base of the bullet - after the bullet has passed the gap. A considerable amount of acceleration of the bullet occurs even before the bullet base reaches the gap.
I mentioned on another thread about the gas blow-by on my Ruger SP101 when I'm shooting .327 Federal magnum.It's much worse than what happens with my Python.The Python is a better made weapon for sure,but I think the hew round operates at even higher pressure than the .357.I wonder what that will mean for wear.Nobody can accuse Ruger of underbuilding their revolvers so it should be interesting.