Question on Colt A2 20" upper with M4 feed ramps

[masakari]

Gray Colt CM Forge large pin upper, 20" government profile barrel with flash hider and bayonet lug. Strangely enough, it has what appears to be M4 feed ramps in both the receiver and barrel extension. Upper is NOT marked M4 above gas tube.
I didn't know that they ever made these, thoughts?

[Iraqgunz]

It's not marked M4 above the gas tube, because well it's not. It's most likely from a Colt Model 6520. Some of them were done legit and are anodized, some were not.

Gray Colt CM Forge large pin upper, 20" government profile barrel with flash hider and bayonet lug. Strangely enough, it has what appears to be M4 feed ramps in both the receiver and barrel extension. Upper is NOT marked M4 above gas tube.
I didn't know that they ever made these, thoughts?

[masakari]

It's not marked M4 above the gas tube, because well it's not. It's most likely from a Colt Model 6520. Some of them were done legit and are anodized, some were not.

Understandable, but the 20" barrel also has the feed ramps. And from what I've seen online, most of those 6520 uppers were marked M4.

[81mmcat]

Of the two 6520 uppers I have (bought used from hk specialists) they have the m-4 cuts and are black, one has no markings above the gas tube hole and the other has the number 4 above the hole. They supposedly came from the DOJ and I don't know if they were refinished or not.

[Iraqgunz]

I'll check my upper and see. One thing about Colt, is they have been known to do crazy stuff. Maybe scottryan will chime in?

Understandable, but the 20" barrel also has the feed ramps. And from what I've seen online, most of those 6520 uppers were marked M4.

[Circle_10]

Well for the hell of it, I checked my 6520, 1999 mfg, apparently a former LE gun. I don't have a "4" about the gas tube hole and my feed ramps appear to have been cut post-anodizing although it's somewhat hard to tell because they are dirty at the moment.

[GRA556]

Well for the hell of it, I checked my 6520, 1999 mfg, apparently a former LE gun. I don't have a "4" about the gas tube hole and my feed ramps appear to have been cut post-anodizing although it's somewhat hard to tell because they are dirty at the moment.

Do you have any of the special Colt sear block(s) in the lower receiver on this model?

[ST911]

A batch of 6520 uppers I have are all machined and finished, some Colt Defense and some Colt Canada. One that's handy has a 4 on it. None had sear blocks, nor would I expect them.

[Circle_10]

Do you have any of the special Colt sear block(s) in the lower receiver on this model?

Mine does not have a sear block lower.

[scottryan]

Gray Colt CM Forge large pin upper, 20" government profile barrel with flash hider and bayonet lug. Strangely enough, it has what appears to be M4 feed ramps in both the receiver and barrel extension. Upper is NOT marked M4 above gas tube.
I didn't know that they ever made these, thoughts?

That upper has been modified by an aftermarket party. It is too old to be relevant to any other discussion in this thread.

Colt only did non-anodized feedramps during 1999-2000ish on some 6520s.