Put a bump fire stock on a Bushmaster AR-15 with high capacity magazines and you get this:

[Kaleva]

This video is almost 8 minutes long but you'll see why some folks don't want to give up their high capacity (so called "standard&quot magazines. This device is perfectly legal and is also available to install on semi-auto AK-47 clones.

If one wants to take the time, there are numerous videos on youtube showing how to "bump fire" most any semi-automatic long gun even without a special bump fire stock as shown in the video. Bump firing allows a shooter to send a wall of lead down range in seconds and the technique works best with rifles that are fitted with high capacity magazines.

Hard core pro-gunners will poo-poo bump firing and say shooting a gun that way isn't accurate. Well, it's as accurate as firing a fully automatic M-16 shooting the same ammo as the AR-15 or a fully auto AK-47 firing the same ammo as a semi-auto only AK-47 clone.

I've posted about bump firing before in GC/RKBA but it is quickly dismissed and I think it's because some hard core pro-gunners don't want the average lay person to know what one can do, legally, with a semi-automatic rifle fitted with high capacity magazines but that is just my opinion.

This is a link to the letter from BATFE stating the bump fire stock as shown in the video is legal:

http://www.slidefire.com/downloads/BATFE.pdf

[NYC_SKP]

1. For others here, I will explain how the "bump fire" principle works:

Ahem.

This video in the OP shows it pretty well-

Imagine your trigger finger staying still and the weapon rocking forward and aft as a result of recoil, just far enough for each discharge to cause another firing.

This is basically how it works, you don't actually pull the trigger each time, the weapon jolts back and forth with just the right timing and force to behave like a fully automatic weapon, sort of.

What I've never understood, however, is what the attraction is for ANYONE for fully automatic firing.

In practically any real life or death situation, the user would NOT want to wast ammunition is such a way, and full auto firing is almost invariably less accurate, so even MORE wasteful.

Anyway, that's my lesson for the day on how the "bump fire" principle works.

This stock design looks more sophisticated than earlier devices.

I wouldn't say that it makes the AR-15 more deadly. Just more wasteful and noisy.

[aikoaiko]

6. This action requires the shooter to pull the rifle against the finger each time it fires.

[NYC_SKP]

11. Well, no, not quite. It's more of just holding still and letting the rifle do the work.

A distinction without a difference, perhaps, but the rifle does the work. The user doesn't do anything "each time", they just hold still pulling with a constant force.

There's a sort of "sweet spot" of tension between pulling too hard and not hard enough where, once you've reached it, the gun does the work of bumping back and forth while the user basically holds still.

Thus, for example, this device won't work while a person is running, or jumping, or otherwise moving around.

All of which is another reason that nobody including the BATF is particularly concerned.

[loli phabay]

17. when you use one of these you are right about not moving

I just moved a couple of steps and it tokk time to refind the sweet spot on the trigger. Mayby with practice j could but unless i stood stock still it was non instinctive. Also it didnt feel as natural or as fast as when i use my m16 on full auto.

[backwoodsbob]

23. please post a pic

of your full auto m16

[loli phabay]

28. dont have any pics of any of my guns just google it just a bog standard old style m16

Wouldnt be surprised if it was a nam surplus.

[backwoodsbob]

29. no I would like pics...preferably video

and a description of the process you went through to get the license.

Would LOVE to see a video of you ripping off a clip in full auto..please make one and post it

[loli phabay]

30. sorry no pics or video

[backwoodsbob]

32. you're full of shit

you just sent me a PM saying they ISSUED you an m16 as your patrol rifle as a deputy in Virginia...BULLSHIT!

What county and what station are you dispatched out of where they issue m16's to deputies as patrol rifles?

[loli phabay]

33. seeing as if i sent you that info you would just run here and out me then go chase yourself

Just go google patrol rifle and virginia and yoj will easily see not only discussions but classes in patrol rifles throughout va including m4 m16 and dedicated rifles.

[backwoodsbob]

35. you're full of shit

go away troll

[loli phabay]

38. i take it you dont have the courage to do the search or to say you are wrong

Ill even help you words that will help with your search are patrol rifle virginia. I doubt you have the guts though.

[backwoodsbob]

41. took your challenge

here

http://www.defensivecarry.com/forum/defensive-carry-tactical-training/66679-patrol-rifle-carbine-course-charlottesville-va-march-27-28-a.html

NO MACHINE GUNS!

[loli phabay]

43. one link to a private firm is that the best you can do

Why not go look at the forums that should pop up with talk of the patrol m4a1 and m16a1

[backwoodsbob]

36. until a year ago i lived in Virginia..I KNOW MANY deputies

NO VIRGINIA DEPUTY is issued a machine gun as a standard issue patrol rifle

[Kaleva]

10. Bump firing is as wasteful as any select fire weapon

There's a reason why soldiers and many law enforcement tactical groups prefer a select fire gun over one that is strickly semi-auto and these folks are often in life and death situations.

[MightyMopar]

2. Doesn't this fire as fast as the old machine guns that were banned by the NFA?

[Kaleva]

3. Almost as fast

But bump firing still requires that the trigger be pulled once for every round fired and so isn't covered by NFA.

[ProgressiveProfessor]

12. No, not even close

[MightyMopar]

16. Professor, I think you're wrong

Slide Fire Stock: This IS the Machine Gun You’re Looking For
Posted on September 12, 2012 by Robert Farago

admit it: I was skeptical. An ATF-legal stock that transforms an AR from a semi-automatic rifle to a fully automatic machine gun? To paraphrase the B52?s immortal hit Planet Claire, WELL IT DOESN’T! Otherwise, it wouldn’t be legal would it? What the Slide Fire stock does is make a semi-auto’s trigger very, very fast. So fast, in fact, that the difference between a rifle so equipped and one with a giggle switch is relatively unimportant. Especially as machine guns are pricey and paperwork-intensive.

http://www.thetruthaboutguns.com/2012/09/robert-farago/slide-fire-stock-this-is-the-machine-gun-youre-looking-for/

[ProgressiveProfessor]

50. I am not a "journalist", I deal in facts, metrics, and details

I have fired this device and its numerous predecessors and understand what it can do and its limitation

I have never heard of a selector called a "giggle switch".

Any damn fool can have a website, and many do. This is a classic example of that.

[hack89]

4. Can you show a single crime committed by such a device?

looks like a novelty item to me - aimed fire is much more dangerous. You can't really aim with this.

[TheBlackAdder]

8. The demonstrator was able to maintain a close grouping when fired into the pond. eom

[Kaleva]

14. No but I can show you many crimes commited with a semi-auto.

Your arguement is kinda like saying semi-automatics are much more dangerous then full automatics. Following that line of reasoning, then semi-automatics ought to be more strictly regulated then full auto only guns.

[Paladin]

21. And The Crime Rate Involving Legally-Owned FULL Automatics Is...Pretty Much Zero.

The Gun Enthusiasts used to point to this fact with pride---until me and a few others mentioned that it was irrefutable proof-positive that, contrary to gun militancy blather, gun control DOES work. Let me just emphasize that: When guns are properly controlled, crimes involving guns are reduced.

[cheesymonkey]

57. Evidence, not proof

The fact that legally owned full-autos is pretty much zero is not "irrefutable proof-positive that...gun control DOES work." It is simply evidence. There are a number of other factors at work that mean we shouldn't automatically conclude that gun control works.

1) There are a number crimes committed with illegal full-autos, though that number is also small. To really say that full-auto gun control is effective, it also needs to have an impact on the guns that are illegally made or imported.

2) The number of crimes committed with legally owned full-autos has been pretty much zero since the 1930s. (It may have been pretty much zero before that. I haven't looked into that.) I think this is pretty good evidence that the 1986 ban on the new manufacture/import of full-autos for civilians was completely unnecessary.

3) The number of crimes committed with legally owned full-autos stayed pretty much zero all the way up to 1986, despite the fact that inflation made the $200 tax stamp significantly cheaper, which increased the availability/affordability of full-auto guns. This implies that the tax stamp (which was partially intended to make full-auto guns prohibitively expensive) was unnecessary.

4) Most crime, including murder, is not made significantly easier for the criminal by having a full-auto instead of a semi-auto. Full-auto only really makes a difference when the attacker intends to harm more than a few people. When one weapon becomes more expensive to get (either in terms of price or in terms of the risk of punishment) criminals simply switch to a different weapon. When the weapons are similar in their effectiveness, then crime rates don't drop.

5) To measure the effectiveness of the full-auto gun control, you need to compare before and after the changes were made. Like I mentioned earlier, the crime rates for legal full-autos didn't really change before and after 1986 ban. But we also need to compare before and after the restrictions added in the 1930s. I don't know the stats on this. But if full-autos were rarely used in crime before the 1930s, then we can't really conclude that the gun control of full-autos was successful. And even if you do care to dig up those stats, you also need to keep in mind all the other factors that changed at around the same time, such as prohibition.

6) It doesn't actually matter if "crimes involving guns are reduced." What matters is that crime overall is reduced. Let's assume for the moment that in the 1920s full-auto gun crime was super high; then after the 1930s gun control full-auto gun crime dropped to pretty much zero. But at the same time semi-auto gun crime increased. Then we aren't better off, and the gun control didn't work. Similarly, if we ban all guns, but criminals just switch to knives instead of choosing to not commit the crimes, then we aren't better off. While crime-by-weapon stats can be helpful in analyzing the situation, at the end of the day, only the overall stats matter.

I'm not saying I can prove that gun control is ineffective. All I'm saying is that real life is too complicated to say that this or that statistic proves (or disproves) gun control.

[Paladin]

59. Thank You For Favoring Me With Your First Post.

And a thoughtful post, at that.

My response is similar to the one I give to those Gun Enthusiasts insisting on rigorously correct usage of gun terminology here at DU: this is an on-line talk site, not a Senate markup session. With respect to your post: yet again, this is a talk site, not a court room. If the evidence vs. proof standard were uniformly applied to the gun matter, this place wouldn't be nearly as lively as it is. Let's just say that I find the lack of violence involving automatic arms to be evidence so compelling that it amounts to proof that gun control works. You are free to differ with my opinion on the matter.

One final thought: that evidence vs. proof standard would be at least as detrimental to the arguments of our Gun Enthusiasts as it would to those of gun restriction advocates, and probably more so.

[MightyMopar]

27. They used to say AR-15's weren't used in crimes, now they're used almost everyday

Once these guns and attachments are more and more in circulation they will be used.

[Recursion]

58. Well, no, they aren't. 2 times in the past several years

They were clustered within a few days of each other, but we're still not even statistically significant here.

[hack89]

37. Not with semi-auto rifles

Rifles and shotguns account for about 3% of all murders. And very few of the suicides which make up the majority of gun deaths. Which makes this fixation on assault weapons nothing more than security theater. To accept the continued legal ownership of semi-automatic handguns is to accept that future mass shootings like VT are a certainty.

The majority of mass shooting (more than four victims) involved handguns. The worst one in recent history, the Va Tech shooting, involved two handguns with standard magazines.

There will be one shot at the gun control ring. If you only have one shot at it for the next decade or so, why not do something that addresses the vast majority of gun violence?

[Kaleva]

40. I'll refer you to this post of mine in GC/RKBA

I include semi-auto handguns:

http://www.democraticunderground.com/117297510

[hack89]

42. Posts like that actually reasure me about the future

it is those that actually propose realistic ideas that get my attention. I hope there are more like you out there.

[polemic_realism]

5. well, there you go...

that poor "deer" never had a chance.

Jeez, our populace is militarized.
This video is enough proof for any rational person that something has to change.

[Paladin]

7. Consider The Kind Of Personality That Finds This Sort Of Feature Attractive.

This video has been around the DU Gun Control/RKBA group for a while. Like all matters having to do with pseudo-machine guns, our resident Gun Enthusiasts' gleeful response to bump fire has all the maturity and intelligence of a group of 13 year-old boys watching a porno film. Firearms used to be designed for grown-ups; not anymore.....

[TheBlackAdder]

9. Even Remo Williams couldn't dodge that! eom

[ProgressiveProfessor]

13. False post on several points

high capacity (so called "standard&quot magazines

They are the standard magazines

Bump firing allows a shooter to send a wall of lead down range in seconds

The bump stock is no faster than other semi automatic operation

technique works best with rifles that are fitted with high capacity magazines.

The bump stock is independent of magazine capacity

I've posted about bump firing before in GC/RKBA but it is quickly dismissed

Am I the only one who finds it odd that you reposted a clear gun thread not related in any way to Newtown in GD when you did not get the reaction you wanted? I note that it is getting the same treatment here.

I have shot this one (and its many predecessors). Its a money maker for patent holder/manufacturer and ammunition providers. Its useless for any kind of aimed fire. It makes ARs noisier but that is about it.

[Kaleva]

15. My response

"They are the standard magazines "

Depends on how one defines "standard". A standard long gun magazine capacity for hunting in Michigan is 5 rounds.

"The bump stock is no faster than other semi automatic operation "

It is faster. From an article:

"With practice, a shooter may control his rate of fire from 400 to 800 rounds per minute, or shoot two, three, or four rounds at a time, and just as easily fire single shots."

http://www.shootingtimes.com/2011/07/22/shoot-your-ar-15-faster-than-ever-with-a-slide-fire-stock/

Can you pull a trigger 400-800 times in a minute?

"The bump stock is independent of magazine capacity"

True but the technique is better used with what you always call "standard" magazines.

"Am I the only one who finds it odd that you reposted a clear gun thread not related in any way to Newtown in GD when you did not get the reaction you wanted? I note that it is getting the same treatment here. "

Yes, you probably are the only one or one of a few. I've posted about bump firing in GC/RKBA months ago. I wouldn't have posted this thread in GD f there had not been a gun thread holiday here in effect.

[MightyMopar]

22. No answer from the "professor" to Farago's truthaboutguns article about bumpfiring

Must be tiring "educating" for the

[ProgressiveProfessor]

44. No, just had some friends visit

And we even did some shooting.

[Lizzie Poppet]

45. "Can you pull a trigger 400-800 times in a minute? "

No. And neither can someone using bump firing. That's the theoretical cyclical rate, which presumes an unlimited, uninterrupted supply of ammunition. The actual effective rate is a relatively small fraction of that, and while it would be higher for bump-firing, that difference would virtually disappear if the shooter was actually intending to hit what they were aiming at.

[ProgressiveProfessor]

47. A a counter

Depends on how one defines "standard". A standard long gun magazine capacity for hunting in Michigan is 5 rounds.

Hunting is not the only use for a rifle and is not the defining item for what is standard. In terms of shotguns, just about all of them have a 5 round magazines though most states require a restrictor that limits it to 3 round capacity while hunting. As for AR format rifles, most manufacturers include two magazine of at least 20 round capacity with each rifle.

It is faster. From an article:

"With practice, a shooter may control his rate of fire from 400 to 800 rounds per minute, or shoot two, three, or four rounds at a time, and just as easily fire single shots."

The article is wrong. The cyclic rate of the action is 600 rpm (what a full auto variant can fire). However even then there are heating consideration. Even larger belt fed, crew served machine guns cannot maintain that rate of fire.

Can you pull a trigger 400-800 times in a minute?

All that question says it that you are clueless about modern semiautomatic firearms.

You are clearly confused about instantaneous rates vs sustained. There was a guy who used to be Governor out here in CA that did not get that either. You might want to leave the technical stuff to people who get it, since you clearly do not.

Bump stocks and their predecessors have been around for a long time. They are a noisy way to burn a lot of rounds in a hurry, but are limited by heat issues. I have not seen where one was used in a crime or used for much of anything. They are like doodads on a Harley. Bling but of little or no practical use.

Some of us have shot them, have you?

[MightyMopar]

49. Farago is one of the biggest gun nuts on the planet, I'll take his word over yours

[ProgressiveProfessor]

51. Actually that is why you should not

I don't have a website and online activities I need to support. He does.

He is a more of a huckster. I serious doubt you have met real gun nutters.

[MightyMopar]

53. Start your own column if your such an expert

[ProgressiveProfessor]

55. I do better than that, I teach...impacts more people positively

[Kaleva]

56. My counter-response

"Hunting is not the only use for a rifle and is not the defining item for what is standard. In terms of shotguns, just about all of them have a 5 round magazines though most states require a restrictor that limits it to 3 round capacity while hunting. As for AR format rifles, most manufacturers include two magazine of at least 20 round capacity with each rifle. "

Again, what is standard is in the eye of the beholder. Back when the AWB was in effect, a 10 round limit on magazine was the standard and anything over that was high capacity.

"The article is wrong. The cyclic rate of the action is 600 rpm (what a full auto variant can fire). However even then there are heating consideration. Even larger belt fed, crew served machine guns cannot maintain that rate of fire. "

Not accurate but not wrong either as it's in the ball park of what one can do while bump firing. Nothing you have said above supports your view that one can fire a semi-automatic normally just as one can using a bump fire slide stock.

"All that question says it that you are clueless about modern semiautomatic firearms. "

Which is just your way of saying "I can't answer your question so I'm going to attack you instead."

"Bump stocks and their predecessors have been around for a long time. They are a noisy way to burn a lot of rounds in a hurry, but are limited by heat issues."

So by saying there are heat issues, you are saying one can fire a semi-automatic faster with a slide stock or just using the bump firing technique. Here is what you said in an earlier post:

"The bump stock is no faster than other semi automatic operation".

But then you say there are heat issues with the slide stock. Heat generated by a rapid firing of the gun. Are there the same heat issues with other semi automatic operations? Assuming one is firing the same model gun and has on hand the same number of what you like to refer to as "standard" loaded magazines.

[gulliver]

18. Does it come with a vibrator attachment for a plastic sex doll?

That's seriously what this thing is like. This is one of the stupidest, most pin-headed, most feeble brained contraptions I have seen in a long time. The pigeons will be snapping it up no doubt.

[Downwinder]

19. When, in civilian life, is "field of fire" shooting appropriate?

[ProgressiveProfessor]

48. Depends on context and how it is use

[mokawanis]

20. Let's ban the gun that thing attaches to

and render the bump fire stock obsolete.

[rrneck]

24. Wiggle your right index finger as fast as you can. Same thing. nt

[OneTenthofOnePercent]

25. High capacity mags aren't required for bump firing.

Heck, you don't even need a rifle with a detachable magazine. It's a silly gun-trick. Is there any documented case where a mass shooting used bump firing to increase lethality? Nevertheless, this whole topic is silly - people will never get rid of hicap magazines because any ban that is passed is going to grandfather them anyways.

Bump firing is lame too. When I want to shoot FAST, I just flip the lever from 'semi' to 'auto'.

[MightyMopar]

26. They just run out of ammo quicker!

[Historic NY]

31. We haven't been told by the authorities if the AR's were modified or not....

in any of the shootings & would they even mention it probably not.

[Mopar151]

34. My Dad carried a BAR in WW2

He said "Carrying your own ammo on foot will change your mind about full auto fire." They were trained to do 3-5 shot bursts, as some later mil-spec weapons do.

[Kaleva]

39. 3-5 round bursts are quite possible when bump firing.

The video in the OP shows that.

[backwoodsbob]

52. why would anyone want to make there gun shitty?

I wouldn't do that to a gun for money

[Hoyt]

54. It can be done with a hand gun as well. Here is a fine, "law-abiding" gun owner demonstrating

a technique needed in a civilized society.

http://www.youtube.com/watch?feature=player_detailpage&v=SfDjvhsdQoo