I’ve seen small round, large round, large shaved round but were tear drops ever used on the Colt C7s, specifically in service weapons?

US military use of "C7" style upper receivers was limited to replacement uppers used to rebuild M16A1 rifles and commercial off the shelf weapons, like the Colt RO723 M16A2 carbine, procured for certain special forces units. I'm sure plenty of M16A1 rebuilds with C7 uppers maintained the original tear drop forward assists. All the photos I've collected of the COTS M16A2 carbines used by Delta Force seem to show one of the round button variant forward assists. That's not to say maybe I just haven't seen a photo of one (in the dozens of photos I've collected), or rebuilt guns couldn't have used the tear drop style forward assist, or particular soldiers couldn't have requested it from the unit's armorers.

The tear drop forward assists do pop up on Colt M16A2 series machine guns (RO723, RO733) sold on the civilian market, though.

In my observations of Colt Sporter IIs, which chronologically had all 4 types of uppers and all 3 types of Forward assists, the C7s all had big D forward assists.
The last A1 uppers had Big Ds, and the first A2 Uppers Had Big Ds, but all the C7Uppers had big Ds.

Thanks for the info!

Did the Sporter II’s have the large front pins of the SP1’s?  I have a C7 upper getting cut for a sear that has the standard f/a.  I’m presuming it was switched.

You mean on Cdn C7?  Large shaved round and small round forward assists. I couldn’t tell you if any of the ones from the original contract left Diemaco with small forward assist though.  Colt did help out with parts in early days so there could be a mix of stuff.

I recently became aware that there is a unique forward assist profile that was used by Diemaco. It looks like shaved down Large button FA...







Once you see it, it starts standing out in Diemaco/Colt Canada C7/C8 series pics. I'm guessing that they modified old stock large button FAs until swapping to the USGI type tapered small buttons? Interesting and more of what makes the C7/C8 series my favorite of the platform by far.

Yes, all the sporter 2s with C7 uppers I have seen had the offset 2 screw large front pin.
I posted my observations here. https://www.ar15.com/forums/ar-15/Colt-Sporter-II-Changes-Over-Their-Serial-Number-Range/127-784728/
A mod wrongly moved it to the A2 forum, so it didn't get much traffic.

That's fascinating.
I never knew that.