AR Sponsor
Posted: 3/13/2009 3:26:36 PM EDT
My family of AR-15 uppers built on the LaRue Tactical Stealth billet upper receiver is growing. The Stealth billet receiver is available in two variants; with or without M4 feedramps.
Papa LaRue was assembled to be used for accuracy testing of heavy (75-77 grain) OTM loads. It uses the A3 variant of the Stealth receiver which does not have the M4 feedramps. If features a 24” stainless steel Krieger heavy barrel with a 5.56mm match chamber and a 1:7.7” twist. The barrel is free-floated in a 12” LaRue Tactical handguard. This is the most accurate AR-15 that I currently own, not only with the heavy OTM loads, but with lighter weight bullets also. 
Mama LaRue was put together for the express purpose of firing NATO pressure heavy OTM loads (MK262, 5.56 TAP) safely while hot and as accurately as reasonably possible. The upper sports a 20” stainless steel Noveske DCM heavy barrel. This barrel has a 1:7” twist. The chamber of this barrel is the Noveske NMm0; Noveske Match mod 0. Here’s a quote from Noveske’s website pertaining to this chamber: "The Noveske Match Mod 0 chamber is designed to offer 100% reliability while retaining maximum possible accuracy. The chamber body is slightly larger than the 5.56mm NATO minimum, but within the 5.56 NATO tolerance. The throat is redesigned for proper bullet alignment with the axis of the bore. This chamber was developed to fire MK262 Mod 1 on AUTO in hot environments." Since the Noveske DCM barrel comes with M4 feedramps on the barrel extension, I used the Stealth receiver that has the M4 feedramps for this build. Mama LaRue wears a 13.2” LaRue free-float handguard. Accuracy testing of this rig begins this spring. 
Baby LaRue was designed for the defense of hearth and home. It uses a 14.5” Noveske N4 barrel with a permanently attached Vortex flash suppressor. (In my state, the unwashed masses are not allowed to own such things as SBRs.) The N4 barrels have 5.56mm NATO chambers, are chrome lined and have 1:7” twists. They weigh the same as a Colt 14.5” M4 barrel, but have been re-profiled by eliminating the M203 cut on the barrel and more evenly distributing the weight on the barrel. This upper also uses the Stealth receiver with the M4 feedramps. It has a 9” LaRue free-float handguard which covers the low-profile gas block and gives me plenty of real estate to mount a Surefire X300 white light. 
|
| projektill, your noveske almost certainly has the M4 ramps cut into the barrel exxtension. Look for pics on this sit eto confirm. That being the case, you will need a receiver with matching ramps. The wait to get a stealth upp receiver is many months, as Larue is busy making his own complete uppers. Plus, finding a stealth with m4 cuts will be extremely unlikely for a very long time. Molon seems to have set up his gear back in the good old days, when you could actually find and buy that stuff. . . . . |
my stuff
|
Quoted:
Kewl. You need an SBR, as the baby sister.  If only us peons in my state with permitted to possess such things. I think I must have received a defective copy of the 2nd Amendment. My copy seems to be missing some things, for example, I can't seem to find the words "allow" or "permit" or "less than 16 inches" anywhere in it. 
|
|
Quoted:
projektill, your noveske almost certainly has the M4 ramps cut into the barrel exxtension. Look for pics on this sit eto confirm. That being the case, you will need a receiver with matching ramps. The wait to get a stealth upp receiver is many months, as Larue is busy making his own complete uppers. Plus, finding a stealth with m4 cuts will be extremely unlikely for a very long time. Molon seems to have set up his gear back in the good old days, when you could actually find and buy that stuff. . . . . According to this article on Ar15 rifle with M4 feedramps on the barrel extension and not on the receiver is OK. A receiver with the M4 feedramp and not on the barrel is NOT OK. Here's the link. Topic SIX on M4 feedramps. About AR15 |
|
Quoted:
So I have a question. I'm new to EBRs, and am still kinda pickin stuff up. I have a SS 18in SPR Noveske barrell that I picked up for my first build. Would it work with an A3 larue upper, or do I need to buy an upper with the M4 ramps? Plz forgive my ignorance  yes you can use it on an a3 upper. I have one and haven't had any problems. You cant use a m4 upper with a barrel without M4 cuts |
|
I agree, it can work; but frankly there's no upside of a Larue upper that would warrant a compromise resulting in mismatched feed ramps. That's my opinion, call me anal retentive. Noveske and Larue don't get along, but their stuff works together very well, and you are talking about one of the best barrels with one of the best upper receivers, but they have different feedramps.
The M4 ramps in your barrel extension will be steeper than original; the non ramped receiver doesn't support that angle. Impact on reliability may approach zero, but I don't like the idea of mixing design parameters precisely at the most critical point of the firearm. Molon's statement "these are available in two variants," talking about the stealth uppers, is somewhat misleading. They are not available NOW. They exist, just can't get one. You have a great barrel, but when John Noveske puts together his uppers, he uses forged receivers with matching feedramps. That would be what I would try to do. |
|
Quoted:
I agree, it can work; but frankly there's no upside of a Larue upper that would warrant a compromise resulting in mismatched feed ramps. That's my opinion, call me anal retentive. Noveske and Larue don't get along, but their stuff works together very well, and you are talking about one of the best barrels with one of the best upper receivers, but they have different feedramps. The M4 ramps in your barrel extension will be steeper than original; the non ramped receiver doesn't support that angle. Impact on reliability may approach zero, but I don't like the idea of mixing design parameters precisely at the most critical point of the firearm. Molon's statement "these are available in two variants," talking about the stealth uppers, is somewhat misleading. They are not available NOW. They exist, just can't get one. You have a great barrel, but when John Noveske puts together his uppers, he uses forged receivers with matching feedramps. That would be what I would try to do. How does, "manufactured in two variants", sound? 
|
|
Quoted:
I agree, it can work; but frankly there's no upside of a Larue upper that would warrant a compromise resulting in mismatched feed ramps. That's my opinion, call me anal retentive. Noveske and Larue don't get along, but their stuff works together very well, and you are talking about one of the best barrels with one of the best upper receivers, but they have different feedramps. The M4 ramps in your barrel extension will be steeper than original; the non ramped receiver doesn't support that angle. Impact on reliability may approach zero, but I don't like the idea of mixing design parameters precisely at the most critical point of the firearm. Molon's statement "these are available in two variants," talking about the stealth uppers, is somewhat misleading. They are not available NOW. They exist, just can't get one. You have a great barrel, but when John Noveske puts together his uppers, he uses forged receivers with matching feedramps. That would be what I would try to do. I ordered a CMMG stripped upper that has M4 cuts in it, and it should be here tomorrow. Would this work well with my Noveske barrell? Would there be any real drop in performance between a CMMG upper reciever and something (an unavailable something of course   ) of "higher quality" like a vltor MUR? If it matters, I also have a Young MFG chrome BCG ordered as well. After paying as much as I did for the Noveske barrell, I don't wanna save a few bucks on the reciever if it's going to reduce the effectivness of the barrell
|
| Yes Molon, Stealth uppers have been manufactured in both styles; as you know, but maybe not everyone else here does, Mark Larue does not believe in M4 feedramps. He made up several batches WITH M4 ramps at the request of several dealers, like Denny and Wes. They may or may not be true believers, but their customers are. The current milieu makes it unlikely that the Larue CNC machines will be diverted in any way from their current missions, for the foreseeable future. Of course you could have M4 ramps cut, then refinish the upper Ionbond Diamondblack–– that would be nice. Even so, getting a stripped upper out of the Larue shop is a question of months, as they are focused on complete uppers. Personally, I am coming to the conclusion that uppers do indeed matter. |
|
What mount is this? |
|
GG&G |
|
Quoted:
Yes Molon, Stealth uppers have been manufactured in both styles; as you know, but maybe not everyone else here does, Mark Larue does not believe in M4 feedramps. He made up several batches WITH M4 ramps at the request of several dealers, like Denny and Wes. They may or may not be true believers, but their customers are. The current milieu makes it unlikely that the Larue CNC machines will be diverted in any way from their current missions, for the foreseeable future. Of course you could have M4 ramps cut, then refinish the upper Ionbond Diamondblack–– that would be nice. Even so, getting a stripped upper out of the Larue shop is a question of months, as they are focused on complete uppers. Personally, I am coming to the conclusion that uppers do indeed matter. half way done with my wait.
|
AR Sponsor