I will try to make this a layman's presentation.

First, we have to look at the definition of "assault weapon." 

There is a military definition of "Assault rifle," which is a rifle of intermediate caliber, firing from a closed bolt, in select fire (both self-loading, and automatic or burst), intended for engagements primarily under 200 yards.  Assault rifles are strictly regulated by the National Fireams Act of 1934 (It predates assault rifles by a decade), requiring a background check, law enforcement approval, a $200 tax stamp, and are illegal in 12 states at the state level.  No new ones can be manufactured for civilian sale since 1986.  Current market prices are around $12,000 and up.  My research shows none have ever been used to commit a crime of violence.

There are two cases of registered full autos that were not assault rifles used for violence.  Both perpetrators were law enforcement officers.

Using the AR15 as an example, the civilian version has 7 different components inside, than the military version.  There are ways to convert an AR15 to automatic or burst, but it generally requires a machine shop.  If you have a machine shop and the diagrams, you can illegally make your own anyway without much difficulty.

There have been very few illegal conversions used in crime, for the twofold reason of the complication of doing so, and that autos eat a LOT of ammo.  Regardless of movies, the standard 30 round magazine would be expended in 2.8 seconds.  As anyone who shoots auto can tell you, most of those will miss.  A burst longer than three rounds is rarely of effect.  That even drug dealers aren't mowing each other down with Uzis (not an "assault rifle," btw)(except on TV) should prove that this is really not a concern, even if you could do anything about it, which you can't, unless you plan to ban milling machines.  Except, of course, you can see a previous post where I built several AK style rifles in my garage.

The Congressional and some state definition of an "Assault weapon" attempts to FURTHER restrict guns.  However, there are only a few ways to make a rifle cycle, and any attempt to use those definitions means a ban on common hunting rifles.  Instead, the bans focused on cosmetics.

"Flash hider."  Not having a flash suppressor on a rifle doesn't stop it from shooting, or change its shooting characteristics in any way.  Many modern guns have some form of muzzle brake to reduce recoil or climb, or improve accuracy, and these remained legal.  The only difficulty was that they had to be permanently attached instead of threaded.  This made normal sport and hunting guns more awkward to build, without affecting the ability to shoot, changing the power, or anything else. 

"Grenade launcher."  This was a term deliberately chosen to promote hysteria.  Since the 1950s, NATO nations and many others have used 22mm as the diameter for the flash suppressor/compensator/brake.  There are projectiles that fit over the muzzle device, that are launched with a high power blank cartridge.  These are more powerful than regular blanks, and can damage the weapon.  To make use of this, one would need the blanks, and a 22mm projectile (some are explosive, some illumination, some marking).  Such projectiles are very hard to find and not even used much by the military, if at all.  In 25 years of service, I saw one dummy device.  And since 22mm muzzle brakes were still legal, it made no difference whatsoever.  The presence or absence does not affect the rifle's ability to fire.  Also, they remained legal on non-semi auto rifles, because apparently, grenade launchers aren't dangerous on those. 

"Collapsible or folding stock."  Folding stocks enable a weapon to be transported more easily in a case.  Collapsible, or more accurately, adjustable stocks, are a useful feature because the rifle can be adjusted to fit users of different size, or for various seasons of clothing.  The lack is irrelevant at best, frustrating to legitimate shooters at worse.  It makes no difference on the ability of the weapon to fire.

"Barrel shroud."  This stops you from burning your hand on a weapon that doesn't have an existing handguard.  Relevance?  I'm not really sure.  Of course, you have to be careful how you define it, or useful things like free-floated handguards used in competitive shooting become illegal.  But the gun still shoots.

"Pistol grip."  At one time, guns were straight sticks with barrels banded to them.  These days, we have a much better understanding of ergonomics.  A great many modern guns of every type have pistol grips that enable a more secure grip and better shooting.  The inconvenient workaround is a protrusion from the stock that doesn’t enable quite the same grip on the weapon.  In any case, it makes no difference to the ability of the weapon to fire.

Now, one might ask, "If they don’t affect anything, why do you object?"  This is the wrong question.  If they don't affect anything, by what right do you dictate?  What will you dictate next?  Since there was no negative effect on crime when the ban went away, why should we consider any such laws ever again?

There are ongoing attempts to ban weapons by name.  The problem is, a name can be changed, and, the Courts have ruled that it violates equal protection to name one brand and not another.  How hard is it to change brand names?  Not hard.

So, then it was "AR15s or copies."  No good.  The courts say you must define "copy."  Since the terms address cosmetics only, there's no way to do that.

In fact, California shooters have a brisk business in "off list lowers."  A manufacturer makes an AR compatible lower.  They buy it.  Eventually, CA gets around to adding that brand to its "list."  That means a window opens during which it can be registered as an "assault weapon," and all the evil parts that don't affect shooting can be added, thus creating a valuable new transferrable restricted weapon.

I guess if there wasn't such an obsession with banning them, there wouldn’t be such an obsession with owning them.

"High capacity magazines."  This is not only inciteful, it is dishonest.  The AR15 has had a STANDARD 30 round magazine since 1967 (replacing the original 20 round magazine).  The AK series have had 30 and 40 round magazines since 1947.  What you propose is REDUCED capacity magazines.  But, three 20 rounders are as effective as two thirty rounders, and a magazine change takes about a second. (This, btw, is a clear indicator the opponent in debate knows nothing functional about guns.)  The question of course is, if 20 round limits won't do the job, what's next?  15? 10 (which was the law during the ban)? 5?  Once I allow you to dictate a limit, it can be changed arbitrarily.  After all, you've already vilified my STANDARD CAPACITY magazines by claiming they're "high capacity."

However, this was an item that backfired massively, and why I make the snarky comment that amateurs need to not regulate guns because they'll get hurt.

The AR magazine is the NATO standard, or STANAG.  The British L85, the German G36, the French FAMAS, the Korean Daewoo, and quite a few other rifles take the exact same magazine.  There are approximately 63 bajillion of them in existence (and the manufacturers are cranking out more as we speak).  So a ban on new ones doesn't really have any effect on crime or availability.  There are tens of millions of AKs in the world, and billions of magazines.  And of course, under that pesky 5th Amendment, a ban on possession would mean the government having to buy them from us at market value of $12-$50 each.  Some idiot even proposed registering them, without any thought as to how, or who'd keep the records, or how transfers would be conducted.

Also, this particular item adversely affected military readiness during the ban.

It is understood that magazines are an expendable part of a Soldier's kit.  They should be retained for reuse if possible, but, during a firefight, if damaged, low or empty, one drops the magazine, reloads with a full one, continues the fight and worries about the discarded one after hostilities are concluded.

Except, as of that date, all standard magazines became controlled items, and their loss punishable.

Which meant that I, and every other serving member had to account for them, and during training pay special attention to securing them, to avoid severe administrative headache and punishment.  It turned a disposable metal or plastic shell into something as important and accountable as the weapon itself.

In the midst of a firefight, one should not be concerned about which pocket or pouch one is using to retain magazines that are no longer needed. one should be shooting, maneuvering and communicating.  Yet, that was how we trained, repeatedly, for a decade.  Certainly, we were told that in wartime the magazines became disposable, but that was not what we practiced, so it became ingrained to catch and stuff the empty, not to let it drop and move.

SIDENOTE—gun haters love the concept of "registering" things.  To what end?  You can't inspect my premises without a warrant, and registering cars certainly hasn't had any effect on drunk drivers or accidents.

But, billions of magazines are out there.  And the same is true of common pistol magazines.  So if you're going to design a new gun, you can choose to design with a proprietary magazine of ten rounds, or adapt existing magazines.  The result of this was lots of manufacturers creating new carbines that took existing Glock magazines, and rifles that took AR magazines.

And…during this timeframe, Colt's patent on the AR15 expired, meaning anyone with a Class 07 Federal Firearms License (Manufacturer), could turn out as many AR receivers as they could mill, without paying license fees.  And they did.

The receiver is the numbered part that is legally the weapon in the US.  All other parts attach to it.  Regulation of those parts is impossible, because they're consumable replacement parts, and exist in the trizillions. 

The AR is almost unique in its flexibility.  It can be anything from a .22 caliber pistol to a .458 SOCOM entry carbine in a matter of seconds, just by changing receivers and stocks (assuming your gun is listed as a pistol on its original purchase form, because going the other way, from rifle to pistol, violates a law.  Why?  You tell me, it wasn't a shooter who came up with that idea).  Its basic design, btw, is from 1955, and the first civilian production guns from 1963, which means that in the coming year, it starts to achieve status as a "Curio And Relic," meaning it's more valuable as an historical artifact than as a rifle.  There are specific subrules for C&Rs that avoid much of the paperwork for modern guns.

The AR's lower receiver and trigger group can also be used to operate other weapons or devices.

It is also now used in quite a few modern hunting guns, such as this http://www.remington.com/en/product-families/firearms/centerfire-families/autoloading-model-r-15.aspx which as you can see, is not being marketed for "Shooting up schools."

So, the law changed nothing functional or practical, and instead led to an explosion of new weapons of various designs, and when it went away, nothing changed.

Except one thing:  Gun owners are not inclined to agree to an acceptable level of control, since that level can be changed, until the "right" to keep and bear arms means Airsoft guns.

And thanks to this ruling, we don't have to:

http://www.scotusblog.com/wp-content/uploads/2008/06/07-290.pdf

"Some have made the argument, bordering on the frivolous, that only those arms in existence in the 18th century are protected by the Second Amendment. We do not interpret constitutional rights that way. Just as the First Amendment protects modern forms of communications, e.g., Reno v. American Civil Liberties Union, 521 U. S. 844, 849 (1997), and the Fourth Amendment applies to modern forms of search, e.g., Kyllo v. United States, 533 U. S. 27, 35–36 (2001), the Second Amendment extends, prima facie, to all instruments that constitute bearable arms, even those that were not in existence at the time of the founding."."

So I ask again, politely:  Please address school security, mental health, and the need of the media to glamorize killers.  Because 94 million law abiding citizens didn't kill anyone last year.

http://www.scotusblog.com/wp-content/uploads/2008/06/07-290.pdf
"Some have made the argument, bordering on the frivolous, that only those arms in existence in the 18th century are protected by the Second Amendment. We do not interpret constitutional rights that way. Just as the First Amendment protects modern forms of communications, e.g., Reno v. American Civil Liberties Union, 521 U. S. 844, 849 (1997), and the Fourth Amendment applies to modern forms of search, e.g., Kyllo v. United States, 533 U. S. 27, 35–36 (2001), the Second Amendment extends, prima facie, to all instruments that constitute bearable arms, even those that were not in existence at the time of the founding."."

Those of you who know me are aware I was, and am, an outspoken supporter of the rights of gays to serve in the military, and to marry, even while I was serving in the military.

Likewise, I was, and am, vocal about the rights of pagans, wiccans, atheists and other cultural groups not favored by the Christian majority.

I support reproductive choice for women.

I support these because it's the right thing to do, regardless of my personal feelings.

I chastise conservatives who would like to forget the rights of certain groups, based on their feelings, including recently, those who wished to blame the gay community for the child molestation at Penn State.

The Heller Decision regarding the Second Amendment is linked below, with an important excerpt:

http://www.scotusblog.com/wp-content/uploads/2008/06/07-290.pdf
"Some have made the argument, bordering on the frivolous, that only those arms in existence in the 18th century are protected by the Second Amendment. We do not interpret constitutional rights that way. Just as the First Amendment protects modern forms of communications, e.g., Reno v. American Civil Liberties Union, 521 U. S. 844, 849 (1997), and the Fourth Amendment applies to modern forms of search, e.g., Kyllo v. United States, 533 U. S. 27, 35–36 (2001), the Second Amendment extends, prima facie, to all instruments that constitute bearable arms, even those that were not in existence at the time of the founding."."

I do not ask that you participate in any activity.  

I do ask that you respect the rights of 94 million Americans who were not involved in the incident at Sandy Hook, and who condemn it.

I ask that you return the favor and defend their rights, regardless of your personal feelings.  It is easy to take the moral high ground for a cause one agrees with.  A true challenge for an activist is to support positions one is not comfortable with.

And I ask that you vocally oppose those who claim any such group of Americans enjoys or endorses violence, claims they are lacking in some moral or intellectual fashion, merely for pursuing their Constitutionally guaranteed and court-recognized civil rights.

http://www.michaelzwilliamson.com/politics-The%20Steampunk%20AK47.html

Because I can do that.

And guns aren't going away.

Decades later, we're still having this debate.

First, in the Heller decision, the Supreme Court stated we do have a right to keep and bear arms.  So that means, you are proposing to violate my civil rights.  That's a dead end issue right there.  If you're trying to find ways to violate my rights only to a certain degree in certain ways, you have to expect that I'm going to fight you as much as any other activist fighting someone who is trying to violate their civil rights.  Hating me for that is irrational, and unless you hate other activists for protecting their rights, there's a word for you--the same word that applies to anti-porn crusaders, anti-religion crusaders and anti-press crusaders.

But, if you still want to have this debate, take a look at this:

http://mackeychandler.com/wp-content/uploads/2012/12/Smith2.jpg

A Smith & Wesson.  It dates from 1882.  I have older ones, but this should prove the point.  Guns don't wear out easily.

And this:

http://mackeychandler.com/wp-content/uploads/2012/12/AKOAL.jpg

I fabricated this (completely legally) in my garage.  It's a nice garage, but that's all you need. 

Consider this project by another gentleman:

http://www.northeastshooters.com/vbulletin/threads/179192-DIY-Shovel-AK-photo-tsunami-warning!

And it works for Browning 1919A4 Machine Guns, too:

http://mackeychandler.com/wp-content/uploads/2012/12/browningwhite.jpg

(With a few mods to keep it legal)

Guns are a 700 year old technology.  There are modern machine tools that connect to a PC that will produce just about any automobile, machine or gun part.  The barrel is the hard part, but it's perfectly doable—rifled barrels date back only 500 years.  All that's left is knowledge, and then you run into that tricky First Amendment.

Now, even if it became illegal to do so, the knowledge and tools remain.  If there's a black market for illegal drugs, and there is, why wouldn't there be black market for illegal guns?  Britain has a near total ban on firearms and a ready supply from Eastern Europe.  You don't think Central and South America will be happy to meet our illicit needs?  They already produce of a lot of legal guns for our markets.

But even if you manage that, there are millions of existing guns, almost all of them untraceable, in that I mean the only record is of the original buyer from the original dealer, since 1968.  If you make them illegal, most of them will disappear somewhere, because most people do think that being able to defend themselves is a pretty good idea.  And also:  Black market.

By the way, if you only want to ban certain guns, such as "assault weapons" (Which is a meaningless term, but if it makes you feel happy, enjoy it), we tried that.  First, it had no effect on all the existing ones.  Second, the same rifles kept being made, with minor cosmetic changes to meet the law, because there isn't a workable legal definition of "assault weapon." The courts ruled that attempting to ban by name wasn't workable, by function was too vague, and as long as the silly cosmetic rules were followed, they were perfectly legal, by the millions.

Actually, I MIGHT be able to come up with something that would work to define, say, an AR15 in a way that would legally differentiate it from other weapons.  However, I have no intention of helping you find a loophole to violate my rights, you hater  (That's what we call people opposed to civil rights, isn't it?  Hatey hating haters).

But even if you manage that, and somehow get a Constitutional Amendment AND supporting laws through, then you have the fact that you have to pay for the guns you're seizing—curse that pesky 5th Amendment. It seems as if the entire Constitution is against you.  And you're right.  It is.

So, AR15s, times 15 million, times $1200 average value = a shit ton of money.  Okay, $18 billion.  EIGHTEEN FUCKING BILLION DOLLARS just for one type of weapon.  Figure an average of $500 per gun times 280 million guns…I'll let you do the math. 

Take a deep breath.

Okay, this is reality vs your desires, as I've discussed with quite a few other groups.  You can't get what you want.  The end.

Guns are here, readily available, they're not going away, and half the country will fight your attempt, so you're not going to get it.

Now, would you care to discuss some rational approach to fighting crime?  May I suggest we scale back the War on Drugs?  Improve help for the poor and improve education?  Aren't those things liberals support?

And tell those profiteering media types to stop glamorizing killers.  The First Amendment is about political dissent, using lead type and sketches.  Certainly the Founding Fathers never foresaw instant downloads of graphic death into every phone, for the purpose of selling advertising dollars.  How can one defend a "need" for that right?

Food for thought.