Regarding the D-M4LX

[DocRod]

I'm looking at an M4 for my son's graduation present. Knowing now what I didn't know when I bought my D-M4, the D-M4LX has all the whistles and bells that my young'un thinks are "way too cool", but I'm wondering if this is really what I should be looking at? Aside from cosmetics, ie. folding sights, stock-grip-forend-Phantom flash suppressor, the only real physical difference I can see is the fluted match barrel, and I don't understand the significance of the fluted barrel over the normal barrel.

So I guess what I'm interested in finding out is: What is there for him to gain with the LX over the basic D-M4 other than the cosmetics? There is roughly about $400 difference to go with the LX, so the cost isn't a factor, but I don't want to get him something that is essentially just "Bling" either.

I really need to get your opinions on this as I'm so new to this platform and I'm still wandering around in the dark... but only 1/2 the time now! :cool:

[rob_s]

IMHO your $400 would be better spent on an Aimpoint C3 in ADM mount from G&R Tactical. I think this should be the first upgrade (after installing a "Gapper") to any AR as it just makes shooting (and hitting) that much easier and more enjoyable.

[McQ68]

IMHO your $400 would be better spent on an Aimpoint C3 in ADM mount from G&R Tactical. I think this should be the first upgrade (after installing a "Gapper") to any AR as it just makes shooting (and hitting) that much easier and more enjoyable.
I had to do a search on "Gapper" to make sure I knew what Rob was referring to. Basically, it's a new pistol grip that has a thicker back strap, rather than the slim original, for people who, like Rob and I, have longer fingers. MagPul MIAD, is one of the better ones, comes with several different thickness backstraps. Myself, I just bought the MagPul MOE grip, which doesn't have any backstrap options, therefore somewhat less expensive. You might be an individual who has shorter fingers and the original pistol grip works fine for you though.

[McQ68]

the only real physical difference I can see is the fluted match barrel, and I don't understand the significance of the fluted barrel over the normal barrel. I really need to get your opinions on this as I'm so new to this platform and I'm still wandering around in the dark... but only 1/2 the time now! :cool:
I went to CD website to look at the differences in LE vs LX barrel. LE is 4150 mil-spec, chrome lined, 1X7 twist. LX is 4140, fluted, chrome lined, 1X9 twist. Characteristics of fluting a barrel-looks cool, supposed to aid in allowing the barrel to cool faster(more surface area) and somewhat lighter as the fluting takes off some material. The steel in the LE(4150)is the higher grade grade mil spec, over the 4140. Both are chrome lined(good). The LE twist is faster(1X7)which is said to be more accurate with heavier grain ammo, over the 1X9 twist of the LX. So, the basic questions are: What are you going to use the gun for, what grain ammo are you going to be shooting, and at what distance? Obviously both are good weapons(they're CDs) The LE has a better barrel, but the LX looks cooler. Really can't go wrong with either.

[McQ68]

More thoughts on a fluted barrel. Contrary to a popular myth, fluting a barrel doesn't make it more rigid. As engineers have stated in different magazines "How does removing material from a solid barrel, make it more rigid?" It might "look" more rigid, like those flutes would be reinforcing, but they're not. To actually make it more rigid, you would have to ADD more material, like add reinforcing ribs, on top of the existing barrel to make it more rigid. Fluting=less weight, looks cool, aids(somewhat)in cooling the barrel. 4 more pesos(due to inflation)

[rob_s]

Sorry, should have been more clear. The Gapper (http://www.brownells.com/aspx/NS/store/productdetail.aspx?p=25084&st=&s=) is just a small rubber piece that fills the gap left between the trigger guard and the grip, which (if left un-filled) will rub a hole in your finger in no time.

The absolute minimum upgrade that I do to any AR that comes my way is to install a gapper and an A1 grip, or an old duckbill A1 grip that accomplishes the same thing. I keep a supply of gappers and a couple of A1 grips around, and give the gappers away free and loan out the grips at classes and such when I see people struggling with the god-awful A2 grip. I think I paid a whopping $5/ea for the A1 grips I have.

My only complaint about the new Magpul MOE is that I think they should have included some kind of gap filler and charged $2 more for the thing. It woudn't have impacted sales one bit, and in fact I probably would have bought even more of them.

[rob_s]

More thoughts on a fluted barrel. Contrary to a popular myth, fluting a barrel doesn't make it more rigid. As engineers have stated in different magazines "How does removing material from a solid barrel, make it more rigid?" It might "look" more rigid, like those flutes would be reinforcing, but they're not. To actually make it more rigid, you would have to ADD more material, like add reinforcing ribs, on top of the existing barrel to make it more rigid. Fluting=less weight, looks cool, aids(somewhat)in cooling the barrel. 4 more pesos(due to inflation)


The "more rigid" is a function of weight. A fluted barrel is more rigid than a non-fluted barrel of the same weight.

[McQ68]

The "more rigid" is a function of weight. A fluted barrel is more rigid than a non-fluted barrel of the same weight.
The fluted barrel of the LX model is, correctly, a larger diameter barrel(weighs more) than the barrel of the LE model, which has the 203 cut outs. Therefore the larger diameter barrel of the LX, is stronger than the "standard" size of the LE. It's stronger because it's thicker, not because it has flutes. If you take an one inch barrel and cut flutes in it, it doesn't make that same barrel stronger, it makes it lighter, with the ability to cool faster because of the greater surface area. Removing material from any object doesn't make it stronger, it changes it shape and makes it lighter. Hopefully the clarification helps.

[rob_s]

More rigid is a function of weight. A fluted barrel is more rigid than a non-fluted barrel of the same weight.

It's that simple. People that want to forward an agenda against fluted barrels for whatever reason, or who want to just argue things on the internet, or who just missed the entire point in fluted barrels to begin with, began this whole thing of them being less rigid than a barrel of equal OD. That's not the point. That's like saying that a Dodge Viper is faster than a Dodge Caravan; it's missing the point.

Said another way, if you take two barrels with the same cross-sectional area, one fluted and one not, the fluted barrel will be stronger.

Fluted barrels were developed to be lighter than barrels of the same OD, and more rigid than barrels of the same weight.

It's the same reason we don't build buildings out of solid steel beams, but use I-beams or open-web trusses instead.

[McQ68]

More rigid is a function of weight. A fluted barrel is more rigid than a non-fluted barrel of the same weight.It's that simple. People that want to forward an agenda against fluted barrels for whatever reason, or who want to just argue things on the internet, or who just missed the entire point in fluted barrels to begin with, began this whole thing of them being less rigid than a barrel of equal OD. That's not the point. That's like saying that a Dodge Viper is faster than a Dodge Caravan; it's missing the point.Said another way, if you take two barrels with the same cross-sectional area, one fluted and one not, the fluted barrel will be stronger.
Fluted barrels were developed to be lighter than barrels of the same OD, and more rigid than barrels of the same weight.It's the same reason we don't build buildings out of solid steel beams, but use I-beams or open-web trusses instead.
Rob-I have absolutely nothing against fluted barrels, doesn't affect me one way or another. The OPs original question was about the difference in a fluted vs non fluted barrel. I probably added to the confusion by comparing the LE and LX barrel in the same sentence. I have no hidden agenda or desire for any arguing about something as simple as flutes on a barrel, I have more important things in my life at the moment. We seem to be going back and forth, comparing different points. I actually understand the principles of structural properties and agree with your definitions. Just answer one question about one barrel, not comparing one against another. If you take a barrel with a one inch diameter and cut flutes/grooves in it, does it make that same barrel more rigid/stronger? Just that same barrel.