I'm sure you've all seen the recent posts about the Army's effort to replace the M-16 series with another 5.56 weapon that can be specialized for different roles by switching upper barrel units...

To some extent of course this is already the case with the M-16 series, what with the M-4 and M-203 versions,and the specialist SBR and 10 inch barrel types used by SF operators...

But is this a good idea in the first place? Would it be simpler to issue a "standard" weapon, perhaps with a 16 inch barrel as a compromise? But of course the M-203 will still be in use, and the SF operators will want their micro guns (quite correctly), and there we are tending back to a "systems" approach...

If we want the benefits of a systems approach we could accomplish it with the current M-16; the illustration of the XM-8 system seemed right on target as far as the individual configurations would pan out, except for their "Commando" model, which HAD NO BUTTSTOCK..this would not fly! You can't hit anything without one...

Here's how I see an issue of a systems M-16 series; all would be flat tops with adjustable stocks of the Magpul MSS type and BUIS:

STANDARD MODEL: 14.5 inch light barrel, M-68 aimpoint sight; issued to all non-infantry soldiers and to infantry combat leaders

SHARPSOOTER MODEL: 20 inch light barrel, TA-31 ACOG; two per infantry squad

GRENADIERS MODEL: 14.5 inch light barrel w/M-203, M-68 and/or ballistic computer grenade sight; two per infantry squad

AUTOMATIC MODEL: 20 inch fluted heavy barrel, TA-31, bipod, C-mag system; two per infantry squad

COMPACT MODEL: 10 inch heavy fluted barrel, optics as needed; issued to SF operators and vehicle crews
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I know, most of your complaints would be directed against the "squad auto" vesion, ("What about the M-219 SAW?"), but hear me out:
some gunners have issues with the M-219, mainly the weight when keeping up in squad rushes...but, you say, the M-16 is not really usefull at sustained fire...I say, but then again, neither is the 5.56! The answer? The special forces are getting a 7.62 version of the M-219; this machinegun could and should replace the porky M-240 in infantry units. The "Automatic" model would fall somewhere between a true SAW and a plain assault rifle; this is acceptable given the caliber, and its tactical use.
About the optics: I was including only stuff that is now available. It would be highly desirable to develop two optics: a cheap and rugged reflex for general issue (NOT the current Trijicon one!), and an Integrated Sight Unit: Reflex, with add-on magnification and night-vision modules, plus built-in laser target designator...


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So, give everyone one standard weapon, or let the individual squddie have a specialised type?

Because the OICW will never be issued!

The goal is product improvement, you have not address some of the short comings of the M16 system, like Mr. Lutz mentioned, with the M4PIP, there will be enough private industries producing PIP components that will keep the M16 system running for a very long time.

General use  18 inch with electronic red dot such as Aimpoint or EOTech.

Sharp shooter 18 inch heavy match with ACOG TA31, TA55 or similar scope.

Grenadier either a 18 or 16 inch barrel mid length RAS with the latest HK AG36 again using electronic red dot with build in Granade reticle.

Automatic would be a Shrike system upper with electronic red dot.

compact would be a 11.5 or 14.5 inch upper with electronic red dot.

Of course I wasn't counting out improvements such as the new improved bolt carrier groups...But I take it you also endorse the "modular" upper approach...

The biggest benefit of the system you describe is 90% of the soldiers would have their needs met by an M4.    They would be familiar with the specialty models, could use their ammo and their mags.  I think the development of a simple, rugged, sight which could be bought and issued in volume to reduce unit cost would be the best thing we could do, aside from the M4PIP.  

I would be all in favor of trading the 14.5 with telestock for an 18 without the buffer tube and a 0-10" adjustable stock. :)

The five models cited in the opening post seem most reasonable.  Let's identify some of the developers and their products (and their advantages) that can extend the service life of the AR family and in so doing, kill this XM-8 program.  On behalf of Mr. & Mrs. Taxpayer, I thank you!