I’m new to customizing ARs. I have a Colt 6920 that I’ve been thinking about modifying with a mid-length gas system. I like the looks of the BCM BFH 16" middy, and I was wondering if I would have any problems mounting this on the 6920. I’m just going to buy the stripped upper, and use the Colt’s lower and bolt carrier.
Also, is the extra hundred bucks worth it for the cold hammer forged barrel on the BCM? Thanks.
Please change the title of this post as there is no problem.
Generally speaking you should have no issues at all. Both manufacturers make their stuff to high standards. If you are going to shoot alot I would say that it is worth it.
yea…change the title. and no…you should not have any issues. also…if you have been using the Colt upper and BCG, buy a new BCG for the BCM upper.
Thanks for the replies, and I fixed the title. So you guys think that I should just buy a new bolt carrier group for the BCM upper?
It is pretty standard policy NOT to switch a bolt between two different uppers. If your Colt is new, I’m sure it wouldn’t hurt to use the BCG but for an extra $140 I would just buy a new BCG and charging handle with your BCM upper.
I would actually just shoot the heck out of your 6920 instead of buying another upper, since you already have about the finest 16" upper available.
Yup, if you are buying the upper anyways, you can get a great lower for it just another $350…certainly wouldn’t suck to have a 6920 AND a BCM middy!
My thought exactly. Run enough rounds through that Colt to warrant a new one.
I like mine so much that I want it to be around for awhile so it is designated as a backup during all rifle courses.
Thanks for all the advice. I’m starting to get into carbine shooting and I predict that I’ll probably go through 5k-10k rounds a year. I’ve been trying to take in all the knowledge of this forum, and it sounds like what I need to do is go with the middy. I’m just wondering what kind of life span I can get out of my 6920 with the 16" barrel and carbine length gas system. If I can reliably keep my 6920 for a high round count, maybe that is the way to go.
I’m trying to get into a Colt armorer’s class to help me with my maintenance and repair needs.
I feel confident your Colt will hold up, but if you are going to be doing that much shooting, then it sounds like you need a backup carbine.
That Colt should last for a very long time. Most people on M4C who’s advice I heed seem to prefer the mid-length for a 16" barrel, but I’m sure the difference in overall life expectancy would very negligible. If you plan on shooting 10K per year, I would just buy another 6920 or a BCM clone of your current 6920. That way you have two identical guns instead of having to adjust when swithing back and forth, or just favoring one.
I have a 16" BCM middie and an 14.5" LMT carbine, and honestly wish that I had just built two identical guns (either platform would be fine) instead of one of each.