Machine Guns

Just looking at parts and differences for semi-auto and full auto... Looks
like a full auto just lets the hammer go, the bolt cycles the hammer, when
you let off the trigger, the hammer is caught. For semi-auto, it looks like
the trigger releases the hammer, when the trigger is held, the disconnector
catches the hammer, when the trigger is released, the trigger blocks the
hammer and the disconnector releases. So it looks to me like a semi-auto
would fire full auto if you left the disconnector out, is that correct?
I'm not thinking about making a machine gun but couldn't help noticing it
looks like extra effort to turn an auto into a semi-auto. I wonder, if the
so called "assault rifles" are banned, people that have them undocumented
might as well make them full auto since they would be illegal anyway. I
don't have illegal guns, I have "Undocumented" guns.
RogerN
Reply to
RogerN
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Depends on the type of automatic action. If you're talking about an M-16 then you have it almost correct. If you leave the disconnecter out you would get single shot. Reason being that the hammer would simply follow the bolt and ride it.
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The regulated part of the auto version is actually the auto-sear unit on the right side in the lower animation.
Reply to
Steve W.
google lightening link like this one: thehomegunsmith.com/pdf/fast_bunny.pdf
Reply to
Karl Townsend
Depends on the design. Open-bolt slam-fire designs are the easiest to convert since they're half-way to being a SMG anyway. That's why they're not allowed to be designed and sold in the US anymore. Closed bolt machinegun designs have various methods of holding the hammer or striker cocked until the bolt is closed and locked, then the sear is tripped and the gun fires, repeating until the trigger is released or the gun is empty. Most semi-auto designs will either not work at all if you pull the disconnector, will fire out of battery or will jam. ATF doesn't want any easily converted designs on the market, indeed, "easily converted semi-auto" is part of the definition of "machine gun" in the law. ATF gets to decide what that phrase means. Last I read, they considered 8-10 hours in a fully equipped machine shop to fit that definition. All they have to do is get a gun to double with one pull of the trigger and you go to jail. And with some guns, its not creating full-auto fire that's the real problem, it's getting the gun to stop. Nothing to be messing with without the appropriate license. Used to be, back in a gentler age, they'd settle for confiscation of the gun and a stiff warning. These days, it's pretty much jail AND confiscation of whatever they can get their hands on. Anti-drug and anti-terrorist laws have a lot more bite. All it takes is somebody talking within earshot of somebody with ATF connections and you could be the subject of a serious investigation. Was a case just a few years back where a guy had some M16 parts in his AR, he loaned it out to a friend, it doubled repeatedly at the range, ATF got into it and he was charged with transferring an unregistered machinegun to his buddy as well as having one. Went to jail, cost him a bundle and he'll never legally own a gun again. How trustworthy are your friends? How remote is your range? Somebody can hear it, you can bet on it. Sound of full-auto will draw law enforcement like a magnet.
Stan
Reply to
Stanley Schaefer
On some..some types of actions like the Sten..kinda sorta. Others..not so easy. Turning them off before the magazine is empy can be the hard part.
The methodology of the left has always been:
1. Lie 2. Repeat the lie as many times as possible 3. Have as many people repeat the lie as often as possible 4. Eventually, the uninformed believe the lie 5. The lie will then be made into some form oflaw 6. Then everyone must conform to the lie
Reply to
Gunner
That's what I was wondering about, it would seem to depend on how fast the bolt gets out of the hammer's path, so you have the bolt going pretty fast, the hammer going a bit faster as more bolt clears, then the bolt coming to a sudden stop, that should cause the hammer to have an impact on the firing pin but maybe not enough to fire. I haven't got the animation to load yet (slow internet) but I thought it would be better if the hammer was held back until the bolt was forward.
RogerN
Reply to
RogerN
That's why I'm not planning to make it full auto, though it does sound fun.
My friend was telling me about a guy they go shooting with that can stiff arm most rifles and get them to fire like an auto. He holds his trigger finger still and pulls the trigger up against it, recoil makes his finger release the trigger and his other arm is pulling the trigger back to his finger. I wonder if he's been investigated when people hear "machine gun fire".
But if the anti-gun crowd makes all semi-auto's illegal, and a person is willing to be illegal for their rights, might as well go all out, plus a silencer to prevent the gun from telling on itself as loudly...
RogerN
Reply to
RogerN
A long time ago I used to demo the M-60 - as a pistol.
It's heavy as hell (26 pounds without ammo) but once that first round goes off, it holds itself up...
Impressive, but not terribly accurate that way.
Reply to
Richard
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Bolt speed doesn't make a difference in this area. The hammer would still ride it down without enough force to set off the primer.
The hands down easiest auto to make would be an open bolt design. On those the firing pin is fixed on the bolt face. You cock it by pulling the bolt back and latching it on the sear. When you pull the trigger the spring slams the bolt forward, as it moves it strips a round out of the magazine, chambers it and just as the bolt closes the firing pin hits the primer and the round fires. The recoil slams the bolt back to repeat the cycle. The cyclic rate is VERY high. You can slow it down using heavier bolt weight, gas porting to bleed off some pressure and playing with the spring weights.
The easiest "conversion" candidate would be a blowback operated action. Not much to do to get them to work.
Reply to
Steve W.
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As in the case of my 57-year-old, heavily used High Standard Supermatic .22. When the sear eventually wore over, I was treated to an eight-or ten-shot burst, which ended up pointed almost at the range ceiling and which stopped the firing by everyone else at the range, for an agonizing minute.
It sure was quick. Brrrrrpp!
Reply to
Ed Huntress
An article on "bump stocks" just ran in my local paper:
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"A bump stock fits over a rifle's "buffer tube," replacing the gun's shoulder rest. A "support step" attached to the pistol grip partially covers the trigger opening, preventing contact with the finger. By holding the pistol grip with one hand and pushing forward on the barrel with the other, the finger comes in contact with the trigger. The recoil causes the gun to buck back and forth, "bumping" the trigger..."
Reply to
Leon Fisk
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Yep. Unregulated auto-fire can really burn up ammo (and barrels!)
Reply to
Steve W.
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And now you know the REAL reason they won't allow "Gangsta Style" at a firing range.
Having the muzzle climb Up is a fairly safe direction, but having it spin you around Sideways could be Really, Most Sincerely Bad.
Reply to
Bruce L. Bergman (munged human readable)
"Steve W."
This sounds like the 20mm cannons on the A-1 Skyraider! I spent a year loading these and it was always exciting reloading these cannons. If the bolt sear pin breaks off when charging the bolt the cannon runs till empty... only way to stop it when you charge it is to jam a screwdriver through the belt.... quickly .. The safety was put in after the bolt was charged. Then it was up to the guys on the arming pad to deal with taking it out. ;>)} pdk
Reply to
Phil Kangas
And Bump Fire and Slide Fire stocks give the next best thiing to full auto. And makes shooting rather expensive
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And for $369..you too can have a new plastic toy.
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The methodology of the left has always been:
1. Lie 2. Repeat the lie as many times as possible 3. Have as many people repeat the lie as often as possible 4. Eventually, the uninformed believe the lie 5. The lie will then be made into some form oflaw 6. Then everyone must conform to the lie
Reply to
Gunner
I saw some homemade bump fire type stock modifications. That would be a fun novelty to play with a little bit but I'd prefer it on the 22LR version. A local gun dealer has 5.56 X 45 for $8 per 20, I bought their limit of 2 boxes plus a bag of brass for reloading, if I can find some dies in stock...
RogerN
Reply to
RogerN
I may have spare dies. Small base for ARs?
Let me know and Ill check.
Gunner
The methodology of the left has always been:
1. Lie 2. Repeat the lie as many times as possible 3. Have as many people repeat the lie as often as possible 4. Eventually, the uninformed believe the lie 5. The lie will then be made into some form oflaw 6. Then everyone must conform to the lie
Reply to
Gunner

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