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jeep45238
11-22-2010, 01:26 PM
I recently finished putting together my second AR15, and put a new upper on my first one, and when lubing them last night I got to thinking about what somebody had told me.

*warning, long, cliffnotes at the rear*


They told me that the stock I had one one of them was pointless, to replace it, it's too heavy, and that I shouldn't have bought it for show. Which, if you've figured out anything about me, is odd - I want efficiency in the platforms that I use, and don't care how they look. Ironically, this same person was a huge fan of the AK rifle (as am I), and disliked AR rifles (I like them quite a bit). The irony stems from the weight difference between a standard 7.62x39 AK and a standard M4gery.

I generally like lighter rifles, but there becomes a point of diminishing return, and you will eventually sacrifice reliability for weight. There is something to be said about the heft of a M1, the go-to-heck reliability of their proven war track record, and the same can be said of the AK series. They inspire confidence. They feel like tanks. By the same token, a tank of an AR feels like a toy. Odd I know, but that's the best way I can describe how they differ in feel to me.

One rifle wears a Magpul UBR stock, which is heavy, mounts using a shortened A2 style buffer tube, is adjustable in length, locks up rock solid, and is HEAVY. I love it. Being able to mechanically set a preset LOP, so you just pull the stock out till it stops, and it's the same LOP every time, is dang handy. You can make it shorter by just not extending it out as far, and you can make it longer by pressing the bypass button and pulling the stock further out. On-board storage is a plus too.
http://i151.photobucket.com/albums/s127/jeep45238/Range%20Time/Photo46.jpg

The other rifle wears a Magpul MOE stock, which slides over a standard M4 style buffer tube, and offers a (in my opinion) great increase over the usual M4 collapsable stock. Not much rotational wobble or longitudinal motion in the stock, and the release lever to adjust the length is shielded. If you collapse the stock for storage, you need to either count the clicks out or shoot with the stock fully extended (not always ideal) for a consistent LOP.
http://i151.photobucket.com/albums/s127/jeep45238/Range%20Time/Photo47.jpg

Both rifles have the same handguard, barrel profile and length, one wears a fixed rear sight (the other will wear a folding Troy model in the near future). Both magazines stay loaded at 30 rounds. One is a 5.45x39, the other is a 5.56x43. The 5.56 rifle currently has a USGI sling on it, while the 5.45 runs a Magpul MS2 sling (paracord is now gone though ).

I did some critical thinking about them as I'm waiting for the oven to warm up and shove a turkey in it (early turkey day at my house). Out came the incredibly accurate weight measurement device, commonly known as a bathroom scale, and weights were taken. The question to be answered? How heavy are these things?

5.56 rifle (with 30 rounds loaded, spare bolt/firing pin, bottle of oil, boresnake)= 9 pounds
5.45 rifle (with 30 rounds loaded) = 8.5 pounds
M1 Garand (with 8 rounds loaded, buttstock cleaning kit and grease)= 11 pounds

The internet told me the following weights:
14.5" M4 Carbine (with 30 rounds loaded) = 7 pounds
7.62x39 AK74 (with 30 rounds loaded) = 10 pounds

So, what we find, is that my "too heavy" rifle weighs in at 9 pounds loaded, with spare parts, oil, sling, and maintenence on board. Granted, it currently is missing a rear sight, but that will weigh less than 2 ounces, so let's not split hairs here (let's be honest - I used a bathroom scale for weight measurements).

My "light" rifle weighs 1/2 a pound less, with none of the above mentioned goodies.

This is noticeable after running dry drills for an extended period of time, or long sessions at the range, but is not a huge difference when you just grab a rifle. They're both lighter than a 7.62x39 AK (noticeably, and this was verified with my coworker's WASR2). They're both close in weight to my former 5.45x39 AK74. They're both far lighter than my M1, and haul around an extra 22 rounds of ammunition.

Ok, I get this. Lighter means that the rifle will wear me out nowhere near as quickly, and I can haul some extra stuff for the same weight. Cool.

But...what about balance? I mean, I did mention that in the title, and I hadn't talked about this yet. Well, we all know what a muzzle heavy rifle feels like. It also wears us out. It makes us less steady at the same level of fatigue. The muzzle doesn't want to STOP RIGHT NOW when we transition to a new target. See, when the center of gravity of the rifle is more or less centered in the rifle's overall length, the rifle handles faster, is steadier, and doesn't feel any different in terms of handling when it's stuffed with ammo, or completely empty. Yes, this is a massive rule of thumb, and a great example of a rifle that has this yet feels muzzle heavy is a M1 rifle.

When you look at a rifle with a tape measure, generally the middle point on shorter mag fed carbines is near the mag well. This is a big bit closer to your firing hand than support hand. However, when you start adding gas pistons, lights, lasers, doohickies, forward grips, and thingamabobs, the rifle starts to balance forward, more towards the support hand, though it's length did not increase at all. This will generally result in a rifle that doesn't handle well at all.

On the AR platform, a lot of people oogle over a balance point at the deltaring/barrel nut. I prefer it closer to the rear, ideally centered in the magwell. This gives all the benefits listed two paragraphs above, and feels natural to me, as a handgunner. The light AR15 of mine, the 8.5 pound one? Well, I can't even get it to balance on a magazine on the table, it's muzzle heavy by a fair amount. That "heavy" 5.56 one? Well, it does.
http://i151.photobucket.com/albums/s127/jeep45238/Range%20Time/Photo51.jpg
And it handles better than any AK I have ever tried to run.



In a nutshell, I feel that a heavier, well balanced rifle, will always handle far superior to a super lightweight, poorly balanced rifle. This is in terms of reloading, target transitions, heck, everything. Pick up a Sig 556 and do a few dry drills, then do the same with a A1 AR15, and you'll immediately see the difference.

jlottmc
11-23-2010, 11:30 AM
Look at it like this, if you like it and run it well, then go with it. If it doesn't feel right make it so, or peddle it. There is only one that has to be pleased with it, and that one stares back at you from the mirror. If it works for you then go with it, and don't look back.

jeep45238
11-23-2010, 11:50 AM
I'm extremely happy with how it handles - no worries about that here :)

Now I just need to save up my pennies for another UBR stock to put on the 5.45.