I just picked up my "first 100 released" 901 .308 today. total disappointment as this is sold as a "system"
mine did not come with the .223 adapter, no .223 buffer/spring like all the tests I have seen specify.
selling a conversion capable rifle and not telling the consumer the "kit" is extra is a bullshit bait/switch deal in my
opinion. I'm calling COLT in the am and we will see what their explanation is. otherwise it appears to be a great rifle.
VLTOR stock, TROY rear BUIS, typical cheap colt grip and lockable front folding sight. updates when I get them.

So it's Colt's fault you didn't read what the rifle comes with?

I wrote this in the Colt subforum, but it's clear from everywhere I see selling them that the adapter is not included. Most probably won't want it. I am so stoked to get my first .308, the 556 part is just kinda cool on the side. They will be available later. Tons of Colt 556's are available now.

yes, its marketed as a system. its like touting a piston version without the piston!! I'm not buying the you should have known BS
you guys are spouting. I have read everything I can find on this rifle and never did it say from Colt or anywhere else I can find it
didn't come with the parts to convert, isn't that the pitch? Even Colts website touts the system, then where are the parts??

Since it is marketed as a system did you expect a 5.56 upper too?

no, never said I expected an upper, thats silly, but a $10 adapter and a $50 buffer/spring yes I certainly did expect it.
and I have yet to see any marketing or advertisements that say otherwise, even the test guns come with it. if Colt did
it right they would have a disclaimer  such as "its a modular carbine rlfle, conversion parts NOT included" just saying.....

Well call Colt, they may send you the adapter. Certainly is enough ambiguity around it supporting your position.

There is a YouTube video showing the .223 working fine with the .308 buffer? Just waiting on the adapter and same Colt Spec spare magazines. Mag pul says thier .308 mags will work but the magazines that came with mine have a shoulder to prevent over insertion (first time I've had to use that term ; ) I would also like to replace my trigger. I've read in here Gieselles  will fit, but it looks like the 901 pins will have to be reused as the Reciever is thicker than my .223 or AR10 in that area. Problem is that the stock pins have a bit of play that I would like to remove if I'm bothering with the trigger.  My 901 is very nice overall and I'm sure the after market and copy cats are putting in overtime to sell us some parts?