upper recievers

SwL_Wildcat said:
I'm not 100% convinced about this.

I have a CMMG piston upper. I ran 3K rounds through it a couple weeks ago over 4 days. I was jamming on a regular basis so I stripped the whole thing apart and I found the grove where the square lug that locks and unlocks the bolt rides was worn about 0.050" for about the first inch of the way back. I run wheel bearing grease and never run it dry. I have about 5K rounds through this upper now and I am not very impressed. I have RRA upper I am going to install and monitor the situation.
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All AR15 gets worn out there. The receiver does not "guide" the cam pin. It does not really matter. It is just a recess for the cam pin to go to in the lock up position.

It jams probably because of something else.
 
Got any more pictures of them someplace?
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Like this?

248446_10150204689164016_512014015_7367391_4976637_n.jpg

249451_193431247373895_140872812629739_622646_6734733_n.jpg
 
With the orders we have on the books, we should be running these often.

We are really looking forward to unveiling our quad rails. You guys are going to be shocked by the price. Our distributors in Europe and the U.S a literally giddy.
 
North Eastern Arms said:
With the orders we have on the books, we should be running these often.

We are really looking forward to unveiling our quad rails. You guys are going to be shocked by the price. Our distributors in Europe and the U.S a literally giddy.
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http://1.bp.########.com/_dwCraUxCyCI/RfyKUac1VsI/AAAAAAAAB4A/EZv_uIBm7TU/s400/13schwing.jpg
 
Did not read all 4 pages, does anyone know if they have T markings and M4 feedramp cuts like all the rest.
Im digging the made in canada and that its billet not forged or cast, but T markings and m4 cuts are a must.
bbb
 
There are provisions to have the uppers T Marked, but these out are not.

The M4 Feedramps are part of the Barrel extension, not the receiver. AR uppers do not require extended M4 feedramps machined into the upper unless they're an Auto gun. It's a feature lost on a Semi banger. Adding an extra 2-3mm of ramp into the upper means that you need to integrate the cut into the barrel extension, meaning more expensive extensions, more expensive barrels, more expensive uppers... etc, etc. All NEA Barrels will feature M4 Feed ramps. The SA Uppers will not.. it's not necessary, and an added expense that our customers don't need downloaded to them.

That being said, all NEA FA Uppers for MIL/LEO will be fully cut.
 
DMcFaul said:
There are provisions to have the uppers T Marked, but these out are not.

The M4 Feedramps are part of the Barrel extension, not the receiver. AR uppers do not require extended M4 feedramps machined into the upper unless they're an Auto gun. It's a feature lost on a Semi banger. Adding an extra 2-3mm of ramp into the upper means that you need to integrate the cut into the barrel extension, meaning more expensive extensions, more expensive barrels, more expensive uppers... etc, etc. All NEA Barrels will feature M4 Feed ramps. The SA Uppers will not.. it's not necessary, and an added expense that our customers don't need downloaded to them.

That being said, all NEA FA Uppers for MIL/LEO will be fully cut.
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see i did not know that, all the uppers i hae used has the m4 slots on them.
Good way to save some $$ as you said.
 
Just to be semi-helpful, here is the famous feed ramps image:

feedramps2.jpg


Cuts in the receiver is fine but requires an extension like the one in the upper right, whereas without the cuts you can get away with either sort.

I suppose I would prefer M4 cuts, ideally, just to increase the theoretical feeding reliability, but it really should not make any difference. I can't think of a single malf I have ever seen generated by rifle feed ramps (guys who shoot FA guns may know different, of course).
 
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