Does anyone know why one of these uppers is thin underneath the FSB and the other one is thicker?
Both are genuine Colt uppers.


Does anyone know why one of these uppers is thin underneath the FSB and the other one is thicker?
Both are genuine Colt uppers.


The one got into a fight with a lathe?
Joking.
On a serious note. Perhaps design/specs changed over the course of the design/manufacturing. Perhaps the one barrel allowed for a more common/readily available FSB to be use. When were the uppers bought? What are the profiles beneath the handguards? Those details could lend some idea to what occurred between the two. Which the brain trust around here I am sure there is a reason that can be answered. Am curious myself now.
You beat me to asking that question
The .625" front sight base is being discontinued.
What does the rest of the barrel look like underneath the hand guard on both of these 6933s? The one on top looks like it was machined to .625 and the lower one was machined to .750 for their respective FSBs. Why? Hmmm… Maybe Colt only had .750 FSBs in stock at the time of manufacture.
ETA, Just saw scottryan’s explanation. Please disregard my rambling conjecture!
Makes sense logistically, though the newer style does not look right to me. I believe this is how the 6943 barrels are profiled…Scott, does this mean the newer 6933 barrels are CHF like the 6943 barrel?
Is the .625 FSB being discontinued on all models or just the 6933?
Just on the 6933’s as far as we know.
C4
Aside from President Barack Hussein Obama saying
“You didn’t build that”,
“Trayvon could have been my son”,
“When you spread the wealth around, it’s good for everybody”
“I do believe at some point you’ve made enough money”
“Government investments have made the country great”
“Islam has a proud tradition of tolerance”
and others…
That’s the dumbest thing I’ve ever heard.
We are talking about an inch so I am not sure it has any negative affect on anything.
C4
Why is that the dumbest thing you’ve ever heard? Do you have any additional info?
On what?
C4
The profile under the handguards is the same ?
If you’re gonna go govt profile, I am a huge fan of the .625 but I guess on a commando it doesn’t matter.
Yes, GOVT. LW barrels are a good idea with longer barrels IMHO, but matter not with 11.5’s and shorter.
C4
Any reason given for this? If it’s only for the Commandos streamlining production no longer seems like a viable reason.
I have not asked, but my guess is to make things easier.
C4