I have 6 20 round mags. I never intentionally went out & bought 1. I just ended up with them when I bought my 2 pre-ban AR's. I would like to know what the benefit of having a 20 rounder is, or should I just put them up for trade in the equipment board for good USGI 30 rounders?
I have 2 that have the aluminum followers, & at least 2 are Colt's that came with the rifles.

I like 'em.
They're short and handy.

i just bought 4 of them for the range. it's just a bit easy when bench shooting. other than that............ i don't have a reason.

Prone or bench shooting or personal taste.  Some guys were using these in the Stan ifthat makes a difference to you.  

I'd ask the question.. What do you need 30 rounders for? (over the 20's I mean)   90% of the shooting I do with my AR I load one round at a time. lol  I use a 20 because it's an easy size to work with, but I can;t recall ever loading more than 5 rounds.  I have a 30 bit it's never left the house.

they hold more than 10 round mags[;)]

I have 7 of them and dedicated them to my Varminter.  Great for prone or bench or just low profile shootin'.  Plus since the lead comes 20 to a pack, it's an easy load.

How sad for you.[:(] Nothing wrong with precision shooting, but every now and again I gotta just empty one as quick as I can.

  Want to trade two or three of those for some nice 30 rd USGI mags?

 Currently, I don't have ANY 20 rd mags, and need at least two for competition shooting.  

Please let me know if you can spare 2 or 3 for a trade.  

I would be happy to swap you for some USGI 30rd mags.
I need them for highpower competition. It is easier to go prone with 20s than it is with 30s. And of course the Armalite factory 10rd mags suck a donkeys duck.
I will even pay shipping...

i just like the look of the 20rd mag, plus since a 20 rds come in a box, it works out better.
i do have a lot more 30rd mags than 20s.

Get down and practice shooting over various types of cover, such as a vehicle, wall, or other and notice how much of a lower profile you can present to whomever you are shooting  it with the couple inches lower you can gte with a 20.

Keeping your head 3 inches lower may very well save your ass.

Lower profile when shooting prone....not real important when just blasting paper but REAL important when the targets shoot back.
Allows a mag to be in the rifle when it's cased, such as a drop case for paratroopers, etc.  
20rnders fit easier into pockets, etc.
They just look 'correct' when used in a A1 style AR15.  

I just took stock. I can only find 5 right now, but they are as follows.

1)1 Adventure line with aluminum follower, & missing 1 lip on bottom.

2)1 Sanchez with aluminum follower.

3) 2 Colts in excellent condition.

4) 1 Colt with rivet in floor plate, I believe it's a 5 rnd mag, also in excellent condition.

All five of the 20's I have found are in really good shape. Only the 1 is missing 1 lip on the bottom, but it isn't affecting the mag as far as function, & I know I have 1 more floating around somewhere in my gear.

SHHHHHHH! They may hear you!!!  You wanna end up like our neighbors in Jersey?

If you're shooting from sandbags or other low cover, 20's are the way to go.  Unless you WANT to build up a small mountain of sandbags to clear a 30 over the benchtop, that is.

Most of my mags are 30's, but my 20's are all guaranteed to be used when I go to the range.

CJ

If you carry your rifle more than shooting it, you will appreciate the small size of the 20-rounder mag.  The 30-rounder mag adds considerable bulk to the size of the rifle.

20 rounds is usually enough; I get tired and have to go rest after 20 shots.

what he said.  theyre just alot more ergonomic i guess.

You can jump (parachute) with a 20 rd magazine in your M4. A 30 rd will not fit in the m1950 weapon case.

I own an SP1.

I just can't bring myself to using a 30 rounder in a rifle with triangle forearm, 3 prong FH, and no FA. That's like paining your Porche with Krylon.

Doesn't matter when I jump for I rig the weapon for exposed carry.

I also have my 10rd 22lr magazines for my M261 kit load in 20s.

Hunting season is coming up and I'll trade anybody for a functionable 5 or 10 round mag for either a 20/30 preban.

What good are twenties:

They worked fine until the AK  came out with 30s and then we "needed" 30s too.

I think experienced folks have found the 20s take much less force to jam up an enemies ass as well. (2 kicks vs 3-4)But when you're dedicated to the task at hand (God Bless Our Troops) might as well use a 30.

Both are great. I always have a couple twenties for bench/prone, work.

Mrs. Brady, would you care to buy a vowel?

G_  F_CK  Y_ _ RS_LF!

Why? Because they are DCM/CMP legal, and I prefer them myself over the 30's for the AR's in particular.

I sold my last two Colt 20s to Cnatra.

Mo bullets, mo betta, since 1969.  Most of the web gear out there these days is set up for them and I find them easier to manipulate and I end up using them as a mono-pod when Im prone.

If I ever buy an SP1, I'll probably get a couple again and go old school all the way.

I have 28 20-round mags.  As already mentioned, they are preferred for bench and prone shooting.  In addition, with enough dirt/grime in your rifle/mag, a 30-round mag CAN (but not always) be hard to seat.  The 20-round mags don’t have this problem.

It's an easy way to load 20 round into an AR! [:|]

On top of what's been said already, many people feel the 20 rounders are more reliable. Plus, if you get the ones with the metal follower, you don't have to worry about changing it out. The alloy followers will not tilt anyway. My home defense AR carbine is loaded with a 20 rounder and I have a few spare 20's that are loaded and ready to grab. In a situation such as a home invasion, you may not have time to put on your web gear and all that stuff. The spare 20 rounders are so much easier to stuff in a pocket than the 30's.

-Charging Handle

They work great on the bench, for shooting prairie dogs, they don't get in the way at all like a 30 does, and a 10 just dont have enuff.

They are legal in Maryland whereas 30 rounders are illegal.

If you can carry/use 30, don't carry/use 20.

CRC

From my web site ([url]http://thecurmudgeon.freeservers.com[/url])

In Praise of the Twenty Round Magazine

The key to the reliability of any semi-automatic weapon is the feed system. Faulty magazines are one of the most common causes of malfunctions and using the best magazines available dramatically increases a weapon’s effectiveness. This article will look at available AR-15/M-16 magazines and argue that mil-spec 20 round magazines are the best choice for non-military deployments.

When discussing magazines for the AR-15/M-16 series of weapons, one quickly realizes that there are a plethora of magazine choices. The choices are broad, ranging from 5 round magazine intended for hunting to 100 round drum magazines designed for God knows what. Despite this wide range of choices the most common magazine capacities are twenty and thirty rounds. Of these two sizes, the thirties seem to be the most popular.

I believe that this popularity stems from two causes. First, the added magazine capacity is seen as an advantage. It is believed that thirty round magazines maximize “firepower” minimizing the amount of magazine changes needed to keep a weapon in service. The other reason for the popularity of thirty round magazines is their supply. Put simply, there are hundreds of thousands of thirty round magazines available for sale in the private market. The U.S.’s Armed Forces, and other countries such as Israel, have used thirty round magazines for years and these magazines can be found easily and cheaply.

A less common option is the mil-spec twenty round magazines. These were the original magazines issued with the rifle and most magazines of this capacity were manufactured in the late 1960’s and early 1970’s. These magazines are not as common, nor as cheap, but I believe they are superior to their thirty round brothers.

First, twenty round magazines are considered the most reliable of AR-15/M-16 magazines. The most valuable trait a weapon can possess is reliability. The use of twenty round magazines dramatically increases the reliability of an AR-15/M-16, enhancing its most valuable trait. I believe that this reliability stems in part from the date of manufacture for these magazines. We've all noticed how the quality and workmanship of products seems to decrease with every year. As the twenty round magazines are typically older, they are built better, more durable, and therefore more reliable.

Second, whether in training or an actual gunfight, an operator will be changing magazines. Regardless of whether of a tactical or emergency reload is performed, the magazines will be handled and manipulated. Because of their smaller size, twenty round magazines are easier to handle and manipulate. This is especially evident when performing a tactical reload. Twenty round magazines minimize the chance that a reload will be fumbled and ultimately enhance the rifle’s continuity of fire.

A third advantage of twenty round magazines is their smaller size. As the magazine does not protrude from the lower receiver as much, it provides a lower profile. This profile will allow a lower prone position, allowing the shooter’s head to be lower than it might if using a thirty round magazine. This smaller sized is also advantageous when shooting in the off-hand position. If one shoots in a “perfect” off-hand position, the support arm is perpendicular with the ground. If the support hand is moved towards the rear of the hand guards, a thirty round magazine will dig into the shooter’s arm. This causes the rifle to cant and reduces accuracy. A twenty round magazine protrudes less and extends no further forward than the magazine well itself.

The two final considerations relate more to law enforcement officers. The first potential advantage of using twenty round magazines relates to the use of electric gunlocks. Ideally, for a law enforcement officer, the AR-15/M-16 is carried in the passenger’s compartment of their patrol vehicle in an electric gunlock. There are a variety of electric gunlocks available and some designs limit which magazine a rifle can hold while secured. As valuable as some may think the thirty round magazine to be, given the choice between carrying the rifle with a twenty round magazine already in place or the rifle unloaded with a thirty somewhere in the vehicle, the use of the twenty rounder offers a substantial advantage.

In addition to carrying the weapon in a vehicle, we must also consider where the spare magazine will be carried. There are a variety of magazine carriers for AR-15/M-16 magazines and the ideal model for a LEO quickly attaches to the duty belt. Once on the duty belt, it is important that the magazine not protrude excessively from the carrier, especially if the magazine is carried on the front of the body. If the magazine does not protrude, it will not “dig-in” to the officer’s body and makes carrying the spare more comfortable and likely.

There are those who would argue that extra capacity of a thirty round magazine is beneficial. This is true in a military environment where the weapons are used in large firefights, fully automatic rifles are the norm, and the shooter isn't accountable for every round fired. When the AR-15/M-16 rifle is moved into the civilian arena and used by police officers or private citizens for self-defense, the circumstances surrounding a likely gunfight change dramatically.

One advantage the AR-15/M-16 offers is the ability to end a fight definitively with a small number of rounds fired. The .223 round is an effective fight stopper and the rifle platform used to fire it promises a high likelihood of hits. In this dramatically different, non-military environment, it is hard to imagine firing ten rounds, let alone thirty. For these scenarios, two twenty round magazines, one in the weapon, and a spare, will likely provide sufficient ammunition for any imaginable conflict.*

Please note that I am not arguing that thirty round magazines have no application within the law enforcement or personal defense realm. Certain units, engaged in higher risk operations, such as tactical teams, may well benefit from thirty round magazines. The higher risk nature and dynamic tactics of these operations mean additional rounds are a potential benefit. Additionally, many wise LEO’s carry with them a “emergency bag” or “war bag” in which extra supplies (including ammunition) are carried for atypical incidents. It seems that thirty round magazines have a place in such a bag. If an officer is reaching for such a bag, there is likely a need for as much ammunition as possible.**

A final application for thirty round magazines is ammunition identification. The roles and performance offered by the various 223 loads are broad. Certain rounds are better suited for immediate incapacitation, some for cover penetration, and some for minimal penetration in CQB environments. As it is impossible to find one round that does everything well, it may be wise to carry different loads. In order to avoid confusion, one can only load certain rounds in twenty round magazines and only load other rounds in thirty round magazines. A common example of this is to carry hollowpoints in thirty round magazines, and SS109 rounds in twenty round magazines. The type of ammunition loaded in the weapon is easily known, regardless of lighting conditions.

As noted above, quality twenty round magazine are harder to find and more expensive than thirty round magazines. This is a disadvantage but a minor one, especially when compared to the advantages twenty round magazines offer. It should be remembered that when purchasing any twenty round AR-15/M-16 magazine, it is crucial to only purchase mil-spec aluminum body models. Several companies have manufactured twenty round magazines with steel bodies. In addition to rusting easily, the feed lips are not the same as mil-spec magazines, causing frequent malfunctions. These magazines are worse than worthless and should be avoided (and destroyed if possible).

To summarize, for AR-15/M-16 rifles deployed outside of the military realm, twenty round magazines offer significant advantages not found in other designs. Twenty round magazines are more reliable and durable. Nor do they interfere with common shooting positions and potentially affect the accuracy of fired shots. Finally, there are some situations where the twenty round magazine may be the only choice for carrying the weapon in a loaded and prepared condition.

* Some will naturally question the need to carry a spare magazine at all. Such people will frequently respond that if one carries a single thirty round magazine in the weapon, there is no need to reload. It should be remembered that if a weapon fails to feed properly, the proper response is to discard the likely defective magazine and replace it with a spare. If a spare is not carried, the only option is to clear the malfunction and return the original magazine to the weapon. As the magazine likely caused the malfunction, the rifle will likely fail again.

** This author carries his AR-15 with a single twenty round magazine in place and a spare twenty round magazine in a Wilderness carrier tucked beneath the headrest of the passenger’s seat for ready access. In the trunk, is a tactical vest with three thirty round magazines and other supplies for an atypical incident.

It looks a lot better in a precision AR rig [:D]

With 20-rounders, it's easier to swing your AR out the truck door window to shoot at coyotes...[:p]