Posted on 06/29/2008 3:16:39 PM PDT by Towed_Jumper
DC Has now issued revised firearms registration rules and proceedures following the DC vs. Heller SCOTUS decision
Gas being tapped off from the barrel via a port.
A Garand, AK, FAL and ubiquitous AR each tap some gas in order to cycle the action.
In all these cases but the AR the gas drives a piston that cycles the action.
And we’re starting to see more piston driven AR setups but that’s a discussion for another board.
A Ruger 10/22 is blowback. Nothing but a heavy bolt and a spring.
The 1911 is a delayed unlocking variation of a blowback action.
Recoil gets the slide and barrel moving. A link on the bottom of the barrel (a cam in the case of most derivatives like Glocks, HKs, CZs, etc) pulls the barrel out of engagement with the slide and allows the slide to continue rearward extracting the spent case, ejecting it and pushing a fresh one off the top of the mag and into the chamber.
To continue with crazy corner-cases, there are some folks who frequent the ARFCOM boards refining a gas operated 9x19mm AR.
You can do anything with enough time and money.
Except for the MetalStorm technology there isn’t much new in the field of firearms, there are only refinements.
At least DC isn't in the 9th. :-) However, San Francisco is.
I can't remember the exact numbers, but I believe the 9th Circuit has had more decisions overturned than all the other Circuit Courts combined.
This is the problem...it will take YEARS for this to get back into court and I’ll guarantee you that DC is hopeful that there will be a different mix of SCOTUS justices when it does. Until this happens, their new rules which clearly fly in the face of the ruling will be the way it is.
—PP
And for the record, I would not pass up a deal on a Mateba.
I own a pistol that is more “useless” than either a Mateba or a Deagle.
It’s a Nambu.
Family lore claims that my Great Uncle (mother’s maternal uncle) Lee was shot with (by?) it and beat the shooter to death with an empty M1 Garand and took his Nambu.
The fact is that Uncle Lee brought it back. How he got it is unverifiable.
I bought U.S. made commercial ammo for it in ‘92 and shot it (for laughs) in an IPSC match. My split times on double taps were awesome but the 180 degree safety was kind of slow and the action slamming closed when you pull out the mag slowed down the reloads because the mags don’t drop free.
All in all, it’s useless in the practical sense. It’s great when someone starts telling me about one and then I haul it out.
Maybe I should have characterized the Mateba as impractical and put a smiley after it.
NRA will soon deliver another well desrved b*tch slap.
9th Circuit, the federal appeals court most often overturned by the U.S. Supreme Court
In 2002, it wasn't >50%, but it was noticeably higher than the others.
>So, if I understand this correctly, the advantage is a second or so between a semi and a revolver.
The real advantage is in firepower. - # of shots.
If you should ever need the ability to reload quickly, the automatic is a big plus.
Yep, there you have it.
No doubt they won’t understand the distinctions.
I guess I shouldn’t move to DC and try to register a gatling gun.
A guy in Colorado makes a 1/2 scale .22LR example that is not a rifle or pistol according to ATF.
It is a Title I firearm and only a standard 4473 is required for transfer to us mere mortals.
http://www.gatlingguns.net/
When the AWB finally went away I remember reading where some dirtbag fired an SKS (AK machinegun to the media) at a cop and it was blamed on the AWB sunset.
Still, those taxpayers must pay the bill for city governance.
That ban did not issue forth from Congress.
Only if the bad guy registered his weapon with DC police, otherwise, it's still an illegal gun there, as SCOTUS said that reasonable restrictions were OK, just not outright bans.
...and let's face it, unless the Left stages it with a sacrificial lamb, the next bad guy won't have a registered firearm in DC.
Aside from the whole semi- versus full-auto terminology...
In general, revolvers use a clockwork mechanism to rotate the cylinder to bring the next round into firing position, then raise and drop the hammer to fire.
See: http://science.howstuffworks.com/revolver2.htm
What we call “semi-automatic pistols” used to be called “automatic pistols” as in pulling the trigger automatically reloaded the weapon, or “self-loading pistols” in that the weapon would load the next round into the chamber all by itself after firing.
See: http://www.cybershooters.org/general.htm
(Except, of course, for the previously mentioned exceptions.)
The method that a revolver and a semiauto use to load a new round are completely different.
In a revolver, the energy of recoil and the force of the expanding gases while the bullet is travelling down the barrel are not used for anything, so you feel ALL the recoil forces. Your finger or thumb is what moves the cylinder and cocks the weapon for the next shot, via that clockwork mechanism
In a semi-auto, the energy of recoil and/or the gases are used to work the mechanism that ejects the spent casing, cocks the weapon (optional), strips a round off the top of the magazine, and loads it into the chamber while closing the breech. Thus your felt recoil is less because the weapon is using some of it to “power” its mechanism.
Semiautomatics are generally faster in terms of shot speed (because you don’t have to grind your way between shots with the trigger or hammer), revolvers are technically more accurate (because the barrel and sights do not move). Both weapons can be made sufficiently accurate that the user is the limiting factor, not the weapon. Semiautos also have much higher round counts and faster reload times; in addition, for a given felt recoil level you can get a bigger caliber auto than you can a revolver.
The media will make no mention of the firearm’s provenance. Those pesky little details are left by the wayside in pushing their agenda.
Number of rounds, speed *and* ease of reloading, lower profile for concealment in major large calibers (beginning with “.4” or “.5”), weight per round and felt recoil.
Nobody has made a polymer or carbon fiber revolver for production yet - but there are polymer or CF autos.
Also, depending on the operator and caliber, the difference in shot time can be as much as *three* seconds or more. (.44 Mag N-frame Smith and Wesson revolver vice Desert Eagle .44).
I suppose you're right--old flintlock guns used in dueling, as in Hamilton-Burr, were referred to as "dueling pistols" although they were clearly single shot.
Nevertheless, nowadays for most practical self defense arms, and I presume the interest of the poster, the difference between "pistol" and "revolver" is whether or not loading of the next round is gas-activated. For the purposes of registering under DC's interim rules, "semiautomatic" means gas-activated reloading, and includes just about everything that would be called a pistol for self-defense purposes. Those are, as noted by another poster, still forbidden under DC's new rules.
Several revolvers and variations at above URL.
One famous revolver is the LeMat a 9 shot .44 with a shotgun barrel of about 16 gauge.
Antique Handguns Horst Held
interested in collectible small arms:
A pistol is any handgun that is not a revolver, i.e. muzzle loading single shot. or a pistol like the Thompson Center-Fire in .223 or other rifle calibre, and semi-autos of course.
Uhh, the poster you’re quoting there might have been a little mistaken about the operation of some pistols. There are only a couple of select designs of pistols that are actually gas operated. Most semi-auto rifles on the other hand are gas operated.
If the following post is too long, skip to the summary at the end.
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Most pistols are either blowback or recoil operated. The only gas operated pistol I can think of off the top of my head is the Desert Eagle from IMI. There are other examples to be found in rifle actions scaled down to pistol form, like some of the AR15 and AK derivatives.
You need to understand a few things about firearms and physics first; namely that you are using the rapid deflagration of a pyrotechnic compound to generate copious quantities of hot, expanding gas, and thence using that expansion to propel a projectile. Understand that for every action there is an equal and opposite reaction; so in order to send that hunk of lead down the barrel you’re also placing enough force on the sides and rear to send just as much metal flying just as fast. Hence, why we have thick steel barrels to contain the gasses and channel them towards the muzzle. Problems come into play though, when you consider the breech. It’s generally convenient to have a breech that can be opened or closed, but it needs to be secure enough to withstand the forces placed on it, and it has to have some provision in place to keep superheated gas from working its way through the seams. Hence why we use soft brass cartridge cases (and very ductile mild steel in the case of modern, cheap ammunition), to form a tight gas seal around the chamber and bolt face. That is, during firing the malleable brass expands and fits relatively tightly to the chamber, at least when it’s fully supported at the rear by a solid bolt face. If a cartridge were not fully supported by the chamber, or if it has lots of room to run towards the bolt face (excessive headspace for example), then we get case ruptures. Case ruptures tend to vent superheated gas and a few flecks of hot brass back into the face of the shooter. Ever taken a welding torch to your eyeballs? Yeah, not fun I’d imagine.
Now! Blowback operation uses the weight of the bolt to retard the backwards movement of the cartridge during firing. With a closed-bolt firearm (required due to BATFE regulations in this country, they claim that open-bolt blowback operation is too easy to convert to full auto) blowback can only really safely be used in cartridges less powerful than the 9mm. Delayed blowback is an exception, but it’s really not very common in pistols (delayed blowback tends to be characterized by the presence of a fluted chamber, which if I understand correctly is there so as to further retard movement of the chambered brass after firing). You see, objects at rest tend to stay at rest.
Recoil operation on the other hand is probably going to be the most commonly seen type of operation in semi-auto pistols. Examples would be the Glock and the 1911.
In recoil operation; the bolt and the barrel lock together just prior to firing, preventing the cartridge in the chamber from blowing itself rearward and shredding itself under the intense chamber pressures present. The locked barrel/bolt assembly are allowed free movement over the top of the receiver, so sometime around when the bullet leaves the barrel and the pressure in the firearm is vented the barrel/bolt assembly move along the rails of the receiver due to recoil, where eventually the bolt is unlocked and allowed to move further rearward than the barrel.
As an aside, this is why ‘limp-wristing’ an auto pistol will tend to cause malfunctions. You’ve got to keep the gun itself relatively stable as the barrel/bolt assembly flies back towards you.
Now, gas operation on the other hand is usually only found in rifles. As I said up there, there are a couple of rare exceptions though. Gas operation bleeds some of those superheated gasses from the firing and uses them to actuate some internal mechanical apparatus designed to unlock and cycle the action.
As an aside, I remember a story about how John Moses Browning came upon the idea of using gas to operate his firearms. Old JMB was out with a few friends on the prairie , enjoying some relaxing target practice. With each shot of his friend’s gun, Browning noticed that the sage brush in front of the shooter moved. Shot after shot... “Bang! *rustle*” and “Bang! *rustle*”. Browning saw that there was force being uselessly expelled from the rifle, and started thinking on ways to harness a bit of that force.
He ran straight home and took an old lever-action rifle that he had in his shop and started tinkering. He welded a rail onto the muzzle of the gun, and placed a washer on the rail so that the bullet could pass through the washer, but so that the washer was also likely to catch some of the gas from the muzzle and move along the rail. He tied a string to the washer, and tied the other end of the string onto the lever. He cycled the action, placed the gun in a vice, and remotely fired it...
And to his pleasant surprise, the expanding gas from the muzzle caught the washer and pulled it along the rail with enough force to pull the string tied to the lever, causing the lever to be pulled and cycle the action (partially anyway). All this concept model would have needed would have been a spring mechanism of some form to return the lever to the closed position, completing the cycle of operation.
Now, that was just a concept model, we don’t use rails, washers and string now days. :D
What we do though, is we drill a small hole in the barrel so that when the bullet passes that point some of the superhot gasses propelling it are bled off. Those gasses are bled off into a tube attached to the hole drilled in the barrel, and channeled from there to the firearm’s action. The exact style variable, as for example the AR/M16 family uses direct impingement. But for this example I’m going to use gas op-rods.
The bullet passes the hole in the barrel —>
Gasses are vented into the hole and thence into the gas tube —>
Gasses in the gas tube are forced against the face of the op rod, which is sitting in the gas tube —>
The op rod is forced rearwards—>
The rearward motion of the op rod forces the bolt to unlock and move rearwards—>
The extractor located on the bolt, and hooked on the rim of the cartridge case in the chamber, starts pulling the spent cartridge case to the rear—>
Once the bolt has moved far enough back so that the spent cartridge case is free of the chamber, the ejector located on the bolt sends the case zinging out from the side of the firearm—>
At this point the bolt is so far back that it’s behind the magazine—>
The spring in the magazine forces another loaded cartridge up, resting it in front of the bolt—>
The spring behind the bolt, fully compressed now, forces the bolt forward—>
Which strips a loaded cartridge from the magazine—>
Which is forced into the chamber—>
And the bolt reaches its resting point, and locks into the chamber.
If you squeeze the trigger at this point, lots of other things will happen mechanically, which result in that whole process described above starting over from square one.
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Summary!
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In terms of actual effect, a semi-auto (regardless of the action) will fire one shot per pull of the trigger until you run out of ammo.
In terms of actual effect, a double-action revolver will fire one shot per pull of the trigger until you run out of ammo.
You see, a revolver uses muscle, either that muscle in your thumb or your trigger finger, to accomplish what gas operation, blowback, and recoil operation do in semi-autos.
However, ignorant halfwit politicians who know nothing about firearms seem to think that the muscle operated repeating firearms somehow manage to be less evil and deadly.
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