Trying to find a cheap M-4 upper, I don't want to spend the 600 for a new bushmaster, so I'm looking at other options, it must have:

1, a chrome lined bore and chamber
2, Chambered for 5.56 not .223
3, be postban legal

How about something like this [url=http://webcats.net/store/merchant.mv?Screen=PROD&Store_Code=J&Product_Code=1MM&Category_Code=BU]J&T M4 Upper[/url]?

The J&T upper would be fine, but after adding the cost of upgrading to a chrome lined bore and the price of a bolt and carrier, along with the detachable carry handle my total would come out to 544.95 and then I'm almost back into the bushmaster price range...

Alan- try pricing a custom M4 upper from Adco firearms website:

Std RRA M4 Tac Entry Upper: $527.78
delete tac carry handle and side sling swivel: -$140
add chrome lining: +$35

Total:  422.78 + $4 shipping

Then pick up a slighly used carry handle from the EE board, and you're more than $100 less than BM.

I ordered the same upper from Steve @ Adco and was very pleased with the price and service.  From the opinions I've gotten from this board, the Rock River Upper is very good quality, so you shouldn't be sacrificing much.

Good Luck.

[url=ar15.com/forums/topic.html?b=7&f=22&t=167039]CMMG[/url] on the EE, these prices include the B/BC/CH, they can be ordered without those parts for less.

I'll second the recommendation for Adco. Click on the link that says "build your m4 upper" or something like that and it will display a picture of it configured the way you want it and update the price automaticly. Good folks with fast friendly service and $4 shipping.

After looking at the Adco website I may go with one of their custom built rockriver m-4 uppers, my only question is if I can use my existing bushmaster bolt and carrier, which are relatively new with only 400rds on them.
I know that the bolt and carrier generaly are not suposed to be switched between uppers because of the effect on headspace, but would this be ok for my situation ?