Let’s have some fun with an old review. I’m a huge fan of the M16, as you well know. There was a pretty comprehensive set of changes put in from the M16A1 of my father’s Vietnam-era generation to my generation’s M16A2 (and M16A4, though that’s mostly an M16A2 with a picatinny-rail equipped flattop upper). Let’s look at them one by one, and I’ll tell you what I think. We’re starting from the muzzle end, of course.

Muzzle Device Changes
This is the later “birdcage” flash suppressor with the bottom ports not cut. Meh. I could take these or leave these. I suppose it’s a little better, because it’ll blow less dirt back in the face of the shooter when prone, but that’s hardly a big deal on the M16A1. I guess I’m okay with this, but I’m going to be looking at the price very closely. This isn’t worth a lot to me.

Front sight Changes
This one is really subtle. There were five detents for the M16A1 front sight as you adjust it for elevation. There are four on the M16A2. Because…better? Something about glare and flat faces, I don’t know. I don’t think this one matters.

Barrel Changes
That profile. It’s now fatter…in front of the gas block. The rest of the barrel is unchanged. There is literally no good reason for this. It’s beyond stupid. There were some dumb soldiers using their M16A1 as a prybar. Apparently this was the fix, not discipline. Is there any wonder we’re in such a sorry state now?

There were also some questions of barrel flex, especially under prolonged fire. Well, all that flex is going to happen between the chamber and the gas block. But that part of the barrel was left alone so they didn’t have to make new M203 brackets. A thicker muzzle end won’t do shit besides balance stupid. If this was an actual concern (and I strongly doubt it, but I’m not staring at the data) then they should have added notches or made new M203 brackets.¹

There’s also the subtle matter of new barrel twist. The M16A2 was designed to work with the new SS109/M855 round. The NATO standard 5.56 mm. The Belgians, who developed that round, called for a 1 in 7 twist. Some experts think a 1 in 9 twist would work better. But the Belgians also wanted to make the barrel stabilize the associated tracer round, which was quite a bit longer. So they called for 1 in 7. I can’t blame anyone involved in the M16A2 design for choosing the manufacturer-specified twist rate for the new round.

New Handguards
Okay, these I like. I like these a lot. Way better than the old triangular-type ones. They’re more comfortable. They don’t have those “teeth” things at the top that break. There’s only one kind of part to stock in the inventory instead of two. And they’re better ventilated. Fun for the whole family.

Delta Ring
Colt angled the ring holding the handguards on. The new slip ring (now called the “Delta ring”) was designed to be easier to grab and pull down to remove or replace the handguards. A small change, but a good one.

Brass Deflector
I guess if you shoot rifles wrong-handed, you probably oughtn’t get brass in the face for your trouble. Pretty small change, doesn’t actually impact anything.

Range adjustable sights
Another feature I hate. Unlike the barrel profile, I understand the reasoning. It’s just wrong. These were added because the USMC has a focus on long range rifle marksmanship on known-distance ranges, and also because they wanted something that would do well in high power matches. The sight is better for this. However, the two apertures aren’t very well designed (the big one is too small for its intended use, and the small one is too big for its intended use). Further, I categorically disagree with the train of thought here. Range estimation is hard. Range estimation when you’re getting shot at is very, very hard. Studies have shown that soldiers are really, really bad at range estimation. And the whole point of SCHV rounds is that you have a large point-blank zone. So for the most part, put the sights on target, pull the trigger², and the error should be small enough not to matter. Remember, these are iron sights, and Ivan or Charlie or Haji isn’t going to obligingly stand still at 500 yards and wait for you to shoot him. The original -A1 type sights were better.

Various Lower Receiver Reinforcements
The lower receiver got beefed up a bit in some critical areas. Apparently they were breaking. Anyway, I’m all for stronger, but soldiers can break anything. So I’d really like to see some data on this, in terms of breaking strength and what standard abuse modes will do to it.

New Pistol Grip
You were so close, Colt. So very close. The shape and size are the same as the old grip. But this one is made from a tougher plastic and it has more texture. I like textured grips, and yay tougher. What went wrong? The nub on the front. This is why finger grooves suck. If they fit your hand, they feel good. If they don’t, you’re gonna have a bad time. Because my hands aren’t like the dude that called for the nub, it doesn’t fit my hand right. I’d grind it off, except there are even better grips on the aftermarket. The best of breed are currently the TangoDown Battlegrips.

Burst trigger
I hate hate hate hate hate the burst trigger. Hate it. I hate the conceit that soldiers are too dumb to be trained to use autofire correctly. I hate the conceit that three is the only correct burst size. I hate the notion that the psychological aspect of carrying your own fully automatic rifle in your hands to respond to the enemy’s in kind isn’t worth having. I hate that it means you get three super crappy trigger pulls instead of one mediocre trigger pull. I hate that you never know how many rounds are going to come out, because it doesn’t reset. So, if you have one round in the magazine, the gun will fire the chambered round, plus the one in the mag. You reload. You pull the trigger again. Only one bullet comes out, because the system “remembers” where it left off. You want suppression? Do you need to break contact right fucking now? Automatic fire. Accept no substitutes. I’m so glad this “feature” is dying a much deserved death these days. Probably the worst feature on the gun.

New Stock
I’m split on this. On the one hand, yay tougher. On the other, it’s longer. It’s a great length for prone shooting on a known distance range, slung up with your rifle. It’s less good in combat when you’re using all kinds of positions. Especially if you’re not tall.

Overall, meh. Honestly, the best thing here are the new handguards, and you could easily put those on an M16A1. Also of note is the Diemaco/Colt Canada C7 rifle. Which is an M16A2, but with A1 sights, a safe/semi/auto trigger, and various spacers to adjust the stocks. That’s pretty good. Way better than the M16A2. Sigh.

Now, of course, just buy an M4. Duh. Or M4A1 if you want a barrel that’s in a heavier but sensibly-cut profile. Both are available with a proper safe/semi/auto trigger. The M4 has always been available this way in the catalog. It’s not Colt’s fault some stupid colonels didn’t buy the right triggers.

1.) This issue was finally fixed in the newest M4A1 builds, which use a nice, medium-profile barrel. It’s thicker under the handguards, and there are notches cut in the sides to accommodate the M203 mounting brackets. And, to the surprise of exactly no one, this barrel actually works as intended, holding up to lots of full auto better. There’s a separate question of whether or not this is needed for general issue…
2.) This is why red dot sights work so well on the AR-15 and other SCHV rifles. Modern technology has fixed this issue. Now, everybody uses an optic, whether an Aimpoint or an ACOG. Which is a separate discussion, but any optic will beat good irons, let alone stupid ones like these.