AR Sponsor
Posted: 11/30/2004 6:44:08 PM EDT
| I picked up a few new 20" A2 goverment profile barrels marked E MP C 5.56 NATO 1/7. Any idea who the "E" stand for the barrel maker? There preban chrome lined bore and chamber and I beleive they have a 5 and an F on the front sight base and it is forged with a triangular front handguard cap. Could it be an EABCO or Elisco/Colt barrel? I was told there around 12 years old, yet they look around 20 years old from the petena starting to form. I found through research three different companys over the last 30 years marked there barrels with an "E". Any way to tell who is who from the other markings? |
|
Apparently, these barrels were all recalled and were supposed to be demilled due to problems with rough and/or non-concentric chambers. Someone posted the actual armorer's notice a while back. Some of these barrels had already been surplussed, so I would proceed with extreme caution and skepticism with regards to these barrels. Considering you can get a brand new 20" A2 barrel from Bushmaster with a warranty, I'd not risk purchasing the "E" marked barrel. -Troy |
| There's a six to eight week wait from Bushmaster on A2 goverment barrels with a 1/9 twist right now. I didn't even ask what the wait on a run of 1/7 twists would be. I was told today these are import Elisco /Colt barrels produced in the Phillipines over 30 years ago under license from Colt. Who knows. I did put a microscope in the bore to check for burrs or a rough finish and they are mirror smooth and headspace fine. I ran a glass fiber patch through the bore and it didn't catch any fibers in the bore. I did purchase them from a reputable dealer that's been in the surplus buisness for over 25 years. He's also an ex-goverment inspector from the old tank plant here in Michigan, and a class III manufacture'r so his rep is pretty darn good. When I picked them up yesterday his son didn't seem to knoww alot on there history. That's why I thought I'd ask. Are these the barrels that they were having a problem with? |
|
Only one problem with that, 30 years ago there were no gov. profile A2 1/7 twist "NATO" barrels, so you're looking at 1983ish and newer. If it was a military barrel from 30 years ago it's be a pencil A1 with a 1/12 twist. ________________________________ My pistol and rifle are merely TOOLS, I'M the weapon 
|
| I have an upper with a barrel marked "E MP 5.56 NATO 1/7" - no "C" in the markings at all. The upper is forge marked "E M". It was made by EMCO, who made spare parts for the military awhile back (A1 to A2 conversions - barrels, complete uppers, etc.). They are now out of business. They had a problem with a small number of the barrels having rough machined chambers and this caused a FTE problem. Any rifles with this marking was not allowed to be deployed to a battle field situation due to the problem. |
How about their bolts? The parts game is fun. |
I got two of these awhile back without bolt/carriers. One has since sold and I'll probably use the other for some custom build. Both shot well. |
|
This may be of use. I posted it some time ago but it must have been lost and not archived. Glad it's one of my dissertations that I saved as a Word document........... Anyway. I originally posted this information so the members of this forum would be aware of the existence of these barrels and to prevent someone from potentially making a bad purchase. I thought I’d summarize and repost all of the first hand knowledge I have on this subject since I see this topic surface once a month or so. Over the last year or so a growing problem has surfaced concerning M16A2 barrels made by a certain manufacturer in use by the military. The barrels in question are marked as follows, E MP 5.56 NATO 1/7. They were manufactured by EMCO Ind. of Gadsden, AL., who supplied conversion “kits” to Anniston Army Depot for use during the M16A1 to A2 conversion/rebuild process during the early to mid 90's. I do know that they produced these "kits" for several years between the late 80's and early 90's. There were approximately 90,000 rifles converted using these kits. '95 was said to have been the last year rifles were converted using these parts. Although I have personally inspected rifles with these barrels with rebuild dates into 2000. As far as I can confirm from my sources, EMCO only had a contract to produce conversion kits to be used during rebuilds and did not produce spare parts to be issued to the field for repairs. EMCO is no longer in business. Some, say again, SOME rifles using these barrels have been suffering from failures to extract (FTE), at rates as high as 12% of rifles tested in some units. This initially surfaced at Ft. Dix during the validation process of a deploying Reserve MP unit and was referred to in a subsequent Maintenance Advisory Message (MAM). The overall failure rate is probably around 3-5%. But at 90,000 produced, 2,700-4,500 is a significant number. Upon inspection those rifles were found to have chambers that contained tool marks that were deep enough to cause the brass cases to stick. These malfunctions occurred within 30 rounds and became worse as the chambers heated up. Those rifles received new extractor springs w/ blue inserts and were test fired, FTE. Springs w/ black (M4) inserts were then tried, FTE. Finally the O-ring fix was applied over the M4 springs and the rifles functioned, but not 100%. All rifles with E marked barrels were considered suspect and are not allowed to accompany deploying troops until tested for functioning. As for testing, Rock Island came up with the following procedures for the field. First was to conduct a visual inspection of the chamber for tool marks that look like concentric rings or chatter marks resulting in a rough appearance. Secondly, every rifle was to be function fired with 90 rnds. 30 rnds on Burst, 30 rnds on Semi, followed by 30 more rnds on Burst. This was to heat up the chamber sufficiently to induce a FTE. If the rifle passed it was to be considered deployable, if not it was to have it’s barrel replaced. So far only a small percentage of the significant numbers of these rifles have been found with this defect. Those have been or, are in the process of being fixed with new barrels. Would have been a good plan too, if it could have been implemented/enforced by the MACOMs concerned before bue’coupe misinformation was generated down in the field as to a perceived safety issue. This has resulted in a general lack of confidence of any rifle with one of these barrels. So, now ALL of these barrels are currently being washed out of the system, even though the majority may function fine. It is not known if EMCO ever directly sold off any overruns of these parts. Though there is strong evidence they may have sold a quantity of these either as surplus or, as part of a separate contract for commercial sales as some members of this forum have reporting buying and receiving E marked barrels from DPMS in the early to mid 90’s time frame. Others have reported receiving them as spare parts, assembled on uppers, or on complete rifles bought from Eagle Arms in their pre “Armalite” days. During the length of time they produced them for the military I'm sure some of these parts may have leaked into the civilian marketplace. As with anything the military uses, it is not uncommon to find it in civilian hands so, be forewarned. Since these barrels are actively being replaced, it is possible/probable that most that are currently being offered for sale have undoubtedly bypassed the demilitarization process. If offered an E marked barrel for sale, thoroughly inspect the chamber for tool marks to avoid getting burned. This whole fiasco got me curious as to what other components EMCO produced as part of these conversion kits. So, in the past few months, this is what I've found after inspecting/disassembling and rebarreling a significant number of these rifles. Upper Receiver - marked with forge codes EK or E over MB. Pistol Grip - E at bottom of grip(while looking into it) near the grip screw hole. Hammer - E3 over E, E4 over E, E over M (all on the left side) and E left side with M right side. Trigger - M left side at rear, with E right side above the actual trigger. Semi Disconector - E left side. Burst Lever - E right side. Selector - Marked either E1 or E2 on the top of the lever, visable when in the Safe position, with the raised (nub) indicator on the right side of the selector. Rear sight parts appeared new, but were unmarked. I did notice that all had plastic buffer tube spacers under the buttstocks, but a lot of rebuilt rifles can be found with these. I've even seen there use on new production FN's. Kind of destroys the theory that plastic spacers are aftermarket only. All remaining components such as the Bolts and Carriers were prior production, I.E. Colt or FN that had been refinished. When I first reported on this issue I had erroneously reported on the existence of E marked bolts. Upon closer examination, the few suspect bolts were in fact FN bolts with the underlined F. Since they had been blasted rather roughly before being refinished the F marking was obscured into what appeared to be an E so, EMCO did NOT produce bolts. Other than to be suspicious of any E marked barrel being offered for sale, I don't know if this information is useful or not. But the next time your digging through a parts box at a gunshow and see a strange E coded part, you'll know who made it. Wpns Man |
AR Sponsor