Daniel stopped making them.  Their new one has six bolts instead of a locking collar.

If I was building new (and supply chain problems didn't exist) I'd probably go Larue or big money KAC.  BCM's rail is a little fat, but I own two.

I'm sure there are some other good ones as well (SLR and Geissele come to mind).  There are a whole lot more options today than in the early 2000s. (twenty years ago!).  

We had to provide Picatinny quad rails as the standard was the AN/PEQ-2A and whatever was coming from Rapid Fielding Initiative, so add-ons had to fit without monkeying and without tools.

With all your first-hand knowledge of the subject matter, you should write a book.

...

Where can I preorder?

Put me on the list too!

Been a long road to get these guys finished, but happy to finally show of a nice pair of SDM-R's I built for myself and @USMCSGT0331. Big thanks to sinister, pappym3 and everyone who provided good information to help get all the little details right. Upper receiver is FN M16, no feed ramps, matech rear sight, and early (sub 100k serial number) ACOGs, TA31 and TA01NSN. Barrel is Douglas SS 1:8 twist, M16 extension, turned by CLE to SDM-R profile w/ 12 flutes behind the gas block. Flats were milled for FSB set screws like the AMU did for NM rifles. Painted with high temp rattle can black. FN BCG and had CLE match the bolt to the barrel. One of the handguards is an early Savannah rail, mine is the later Black Creek marked but both have the handguard nuts with the flats. GG&G sling swivels and Harris S-L bipods on no lever stop ARMS #32 bases. Still looking for some tan DD rail covers, but otherwise I think that about covers it, pretty happy with how it turned out. Now we just gotta see how well they shoot...

Those are sick! Any leads on another DD rail? I'm beginning to think the OG SAM-R reproduction railed gas blocks will never come to fruition.

You're probably right.

Awesome!

Great job!

@orpheus762x51 have you had any more contact with the shop?

Original triggers were KAC, only because they already had a TACOM Safety Release and we needed to ship.  We eventually got USSOCOM's Geissele Safety Release through Crane.

The CMP Armalite SDMRs came with an Armalite National Match trigger.  I think the only thing Armalite didn't provide with their 40 training rifles was the DD rail.

Good info! Had heard that they probably had the KAC trigger but wasn't sure if the Geisseles were ever used.

That's a very interesting photo! I've never seen that engraving before. How many CMP/Armalite rifles do you figure are out there?

Thanks! Had a little help knowing what to look out for.

They pop up every once in a while, a DD rail sold on the EE a few months ago if I remember correctly. Just have to keep your eyes out. If you want to stretch clone correctness a little bit, the larue rail is very similar. Just a thought.

It's too bad, the SDM-R and SAM-R are really great, in my opinion under appreciated rifles from the early GWOT, that are hard as hell to clone because of just one or two parts.

I have some tan DD rail covers that have been sitting in my closet for about 10 years if you want them.

I asked Mr. Charlie Maddux, the Director of the National Board for the Promotion of Rifle Practice and Firearms Safety for 40 rifles and TA01B ACOGs for the CMP traveling support program, and he provided all of them.

We at the USAMU had authorizations for M16A2s.  National Match rules didn't change until 2015 (for the 2016 Camp Perry season) to authorize ACOGs and flat-tops, so the commercial rifle stood-in until we could get the Army bureaucratic authorization change.

These were off-the-shelf Armalite National Match rifles they factory-fitted with Daniel rails.  They are as close to USAMU M16A4 DMRs as you can get without the Happy Switch.

The CMP auctioned 12 of them off to the instructors they sent on USAMU Mobile Training Teams after the initial six-year assistance program ended in 2011.

M16A4 SDMRs went away when the Army went to M4s.

The Army's new M110A1 (the modified 7.62mm HK 417 with 1-6X SIG telescope) is the Army's new DM rifle.

============

'Here is a message sent to all the CMP civilian instructors who helped AMU with the SDM training. I personally helped in 4 training sessions at Benning, with SDMs using these rifles through the course.

"Gentlemen,

CMP is offering for sale 12 of the CMP SDM AR-15 rifles exclusively to the Military Rifle Instructors. These are the rifles we used at Ft. Benning for the SDM classes the past six years. The rifles were originally built by Armalite and then later rebarreled by the AMU. They are unique because of the CMP and AMU logo on the lower receiver. Rifles come complete with the Trijicon ACOG scope. Price is $1200 plus shipping. The rifles have been inspected and are considered in good shape, with the normal wear and tear on the rifle and scope. Since the rifles have been used extensively since the last rebarreling, they should not be expected to be as accurate as new rifles.

I expect more responses than there are rifles. Therefore to make it fair to everyone, 12 names will be randomly drawn from all interested MRIs. If you would like to purchase a rifle, I need your response by midnight, 1 September, 2011. Your response is your commitment to buy if selected in the drawing.

Thanks again for all your assistance.

Steve
Marksmanship Coordinator
CMP"'

This one belonged to one of those instructors and was sold at an estate auction:



This is from Louis on the M14Forum:

"So, here is a picture of a group fired prone slow-fire with a sling at 200 yards on the reduced 300 rapid-fire target. X ring 1.9 inches. I sighted in with ball ammo on a target to the right. Then I used 69 grain handloads on this target. First shot was on the 10 line at three. I adjusted the ACOG left, then shot ten more, calling one high and one low (they went a bit left as well).

SDM CMP rifle NO. 34:"

Attached File

These uppers are absolutely perfect, thanks again for taking the time to build mine alongside yours! Neal and I spent hours on the phone discussing and planning these builds, and he spent countless hours researching each individual part so that our uppers were perfect. I can't take credit for anything, he did all the research and work on these, I was just along for the ride, lol.

Has anyone else been building SAM-R's or SDM-R's? I'm thinking about experimenting with having a polished SAM-R barrel blued, then wearing the bluing off of the exposed portion of the barrel in front of the KAC handguard (some steel wool would make this a very easy task). This would match what we see in USMC photos, since the bluing on a polished surface is easily rubbed away when exposed, but was still protected underneath the handguard. This would also help me match the wear pattern on my used KAC FSGB's and FF RAS handguards.

I'd also like to do the seldom seen KAC NT4 variation, has anyone tried to age/wear an NT4 silencer to match other used parts? Most people in this thread have built minty new examples of these rifles, is anyone else using used parts for their build? If so, please post some pics, I'd like some ideas on incorporating new parts with faux patina and well worn original parts.

Just let me take your FSGB off of your hands and be done with this circus. My Bill Wylde upper needs to be something worthwhile!

I wish I had enough original KAC FSGB's to hand out to everyone in this thread, but I need them to complete my builds. I sold my only extra Gen 2 FSGB a few years ago for $2k and I've recently turned down offers in the $3k+ range for my Gen 1 FSGB. The Gen 2's are very rare and the Gen 1's are a true unicorn piece, it took me the better part of a decade searching for them. I wish you the best of luck with your search, it will be a long and expensive endeavor.

I just did.  I'll report back if he has anymore info.

Does anyone know the spec for the SDM-R's fluting depth (how deep the flutes are milled)? Or can possibly get a depth measurement from a CLE or WOA "SDM" barrel?

I shot the 2003/2004 season with a USAMU Krieger cut-rifled chro-moly like what you're describing.  Bluing or parkerizing will give you the weathering you're looking for long before the barrel wears out.

I knew some day someone would ask for this, so I wrote it down on a post-it note I lost long ago.

I am not sure, but I think it was a 5/32 carbide ball end mill, 12 flutes, cutting a quarter-pound (I don't know how deep).  Does 5/32 sound like a typical end-mill size?  It wasn't an exotic.

Are the newer DD rails a functional/structural improvement over the discontinued ones?

My gut opinion would be yes. The way the older style DD's (and LaRue/KAC/etc FF quad rails) worked was that the rail itself was an extrusion, and then a thin coupling tube with threads was slipped in and welded to the rail so that it could attach the handguard to the barrel nut. That's what the welds (4 blobs at 45°, 135°, 225°, 315°) are at the back of the handguard. The handguard acts like a big lever though and can put a ton of force on that coupling piece, especially if you're say loading up weight on a bipod. All the force applied is about as far away from the nut as possible and applying a torque across that coupling.  It's thinnest point is maybe 0.075" if I had to guess. They're known to crack and break there, especially on old KAC FF rails. There are photos somewhere I think of SAM-R's that were repaired there for that exact reason.

The newer DD rails are much beefier in the back there, and they use a clamp to attach directly to the rail extrusion. The lever forces are still there, but just looking at the design, in my opinion it seems to be much stronger since it's countering that force with a 1/2" thick aluminum clamp bracket and 6 screws instead of a relatively thin aluminum tube coupling like the old design. I'm not an engineer though so it's probably more of a scientific wild ass-guess than actual fact.

^^^^^^^
Thanks for the explanation.

@Sinister have you ever seen a SAM-R without a KAC FSGB or the older railed gas block?

Sorry, never operated that close to line Marine infantry so can't say.

I saw a few during the transition to MK12 SPR uppers before the M27.

Everything mentioned about securing quad-rails and tubes to M16 uppers is true about flex and weld cracks.  Look at how Geissele, BCM, and Midwest Night Fighter rails and tubes have evolved and improved -- more rigid cross-sections, longer barrel nuts to prevent flex (so your PEQ-2 through -15 doesn't flex off-zero), and some weight reduction.

The original finish on the tan NT4’s was KG Gunkote, and I suspect the black ones/M4QD’s were same or similar.  Just never verified.  But both style and colors wore in quickly with little use.  Using those and Surefire M4FA’s, the Surefire’s lasted the longest as far as finish durability.  So it shouldn’t be hard to wear in a clone Knight’s if you go have it refinished with KG.

I also challenge you to clone the rifle I had posted on the previous page... you’re about the only one who could pull it off.

Thank you Sinister. Not sure how typical 5/32" is but it gets me in the ball park.

I'm in the process of spec'ing out a barrel that is heavily influenced by the SDM-R, but not an exact clone.

Are you looking to turn one yourself? CLE did the pair for the two I just built and they came out great. If you absolutely can't get the specs anywhere else and you're doing it yourself, I can disassemble it and get you some numbers. Just kind of a pain in the butt, that gas block was a snug fit.

Like I said, Frank, John Holliger, Joe Carlos, John Scandale, Gene Barnett, Quantico, the Navy Team / Crane, a few others -- all these guys are competitors and colleagues and there's a lot of information that gets shared across, and idea-plucking goes on between everyone.

I don't want you to go through all of that but I appreciate the offer brother. Thank you.

Maybe it would have been more accurate (or precise ) to say inspired by or a loose hybrid of the SDM-R and NSWC Crane Recon. Sort of a "Mini SDM-R" style build and not clone correct for either.

I'm actually going to have CLE spin it up from a custom blank.

It will be along the lines of WOA's 16" "SDM" but a heavier profile at the GB journal and just beyond.

GB journal diameter will be larger at .936 or .875 at mid length gas position and then step down to .750 around the rifle length gas position (12").  I don't want the flutes to go deeper than the .936 or .875 diameter of the GB journal so I'm wondering if fluting will even be worth it, if removing only .064 - .125 of material from the 1.00" diameter between the barrel extension and GB journal. I am trying to get an idea of how deep the SDM-R flutes are to compare. I can't imagine that the SDM-R's flute depth would be below the .750 diameter at the SDM-R's GB journal, and if so theoretically they could be up to .250 deep or 2x +/- deeper than I am willing to go.

Just like the automotive realm, competition drives innovation. I wish I could just sit down and record all of these guy's knowledge and experience..that would be amazing!

Update on the repro SAM-R PWS gas block:

James at War Machine says they are swamped and have been for a few months pinning barrels and performing other tasks.
He still really likes the idea of this repro block, and wants to fit it in, but he may not get started until things slow down in the summer.

My take: it could be a while, but it sounds like it will happen eventually.

Nice!  Thanks for heading this up!

Attached File


I needed this good news!

Cool SAM-R photo I just found online. It's pretty rare to see a painted SAM-R.

If anyone is looking for a complete SDM-R upper, I have one available that I'll be posting on the EE soon, figured I'd let y'all know first.

Totally correct build, FN M16 upper, FN BCG, CLE made 1:8" SS Douglas SDM-R barrel with M16 feed ramps, correct fluting, AMU style FSP and bolt was headspaced to the barrel. Has a Black Creek DD M4 12.0 rail with the older/correct faceted handguard nut, GG&G side sling swivel, no lever stop ARMS 32 with Harris S-L bipod, Matech rear and early 29k S/N TA01NSN ACOG. It's turnkey, ready for an A2 lower. PM if you're interested.

(small) update on the repro SAM-R PWS gas block:

Warmachine is finalizing some details on the CAD/CAM side of things.  Should have a prototype soon, then final pricing will be available.

No ETA as of yet, but I wouldn't expect anything super soon.  Still going slow and steady.

@USMCSGT0331
I
That FSGB would cause me to build a rifle just for it

Many people have had that same idea and have tried to buy it from me, but no one has made me an offer I've been interested in

not my photos, but figured I'd share these that were posted in the clone group on Facebook.

Attached File
Attached File
Attached File

SAM-Rs and EMRs

Update from War Machine:

The price is looking like $193 per repro gas block before shipping.

If you're interested, let me know.  He's just waiting on another customer's order to get the volume needed.  $193 is the ballpark as if now, but could go up based on material costs, etc.

I'm interested in one of those repros

@orpheus762x51 I'm still in

Paging @5pt56

I've already been in...I hope anyhow. Lol

I've already got everyone's contact info who contacted me previously.
I'm standing by before I send emails/make phone calls.

If you haven't already, PM me your contact info and I'll reach out when War Machine LLC is ready to produce.

I'd say we're probably still a few weeks, maybe a month or two away.  The CAD/CAM side of things is proofed 100%, we're just waiting on materials and machine time from what he described to me.

I'm in for a FSGB!
I've been following the thread for a while and strait up made an account just to source parts for a SAM-R build.