View Full Version : M-4 Upper Receivers
I recently picked up a Rock River Arms M-4 lower receiver. Initially I wasn't interested in an M16 weapons system or its ilk, but I got it for a good price.
As a Marine I have only had hands on experience with the M16A2 and I have never actually fired a genuine M4.
I know what the gun rags think are good systems, but I was wondering what the rest of you have personal experience with? I would like to know what the professionals on this site think is a good M4 upper.
Another thing that I would like to know is what accesories, if any, you think would be good to go along with it. Don't get me wrong, I'm not a "gear queer", but as a Marine we didn't get the good toys to play with. I prefer to get some reliable personal references before I make a firearms accesory purchase. After all, my life may depend on it some day.
Also, on a tangent, I would like to say thank you to the adminstrators of this site. This was my first foray into the world of forums and it spoiled me. I recently attempted to venture into some other forums and was... well, underwhelmed by the quality control. This is a well moderated and intelligent forum. Again, thank you.
bberkley
04-30-2006, 07:06
If the QP's don't mind, I'll pitch in here (since your question was directed at them).
Fundamentally, there really isn't any difference between lower receivers, so its kind of a misnomer to label a lower receiver a M4 receiver unless it is completely built, and has their 6-position collapsible stock. All of the other parts except buffer tube and buffer are the same as those used in a 20" fixed stock rifle.
If you want to build the rifle up yourself, head over to AR15.com's Build-it-Yourself Forum (http://www.ar15.com/forums/topic.html?b=3&f=4&t=226782) for a list of tools, and illustrated step-by-step instructions. Their equipment exchange forum has a ton of dealers that you can get the gear you are looking for. A good source for tools for working on AR15's can be found at Brownell's (http://www.brownells.com), as well as a good selection of parts to complete your rifle with.
If you want to get an upper already built, and want one of the best in the business, get yourself a MSTN (http://www.mstn.biz) upper receiver. Or you can get one from Rock River Arms (http://www.rockriverarms.com), Bushmaster (http://www.bushmaster.com), DPMS (http://www.dpmsinc.com), or Stag Arms (http://www.stagarms.com/righthalf.htm) among others.
I would suggest trying and building one yourself if you feel so inclined. MSTN offers uppers in 6.8SPC and they generally see .75 moa accuracy with Remington production ammo. The 115gr SMKs will hold moa to 500 yards. Prices for barrel/bolt sets start at $475.
The Reaper
04-30-2006, 08:50
Tubbs:
There are at least 20 threads here dealing with M-4s and assorted accessories, from vertical grips, to forends, to mounts, to stocks, to optics, to lights. You may use the Search function to review them.
Feel free to review any of those and as already noted, there are entire sites like ar15.com dedicated to weapons and gear discussions.
Having said that, while virtually all uppers and lowers are compatible to some degree, Rock River makes very good rifles and components. I would go back to them for the upper, but that is just my personal preference.
As a civilian weapon, I would recommend a 16" 1x7" or 1x9" barrelled flattop upper with a rail forend.
Just my .02, YMMV.
TR
I did view the other threads dealing with M4's on the site. To be honest I am a pistol and shotgun sort of guy. I have a passable knowledge of other small arms, but thats about it. The other articles seemed to deal with the system as a whole. Since my knowlege is based on what I learned about the M16A2 service rifle while I was in, I didn't know if there was a difference.
Plus I've read about and seen first hand in some cases, the horror stories of improporly put together systems. I just didn't really know if since I had a Rock River lower that meant that I had to buy a Rock River upper.
I also didn't know that there were whole sites on the topic. I'm not a big internet fan. I treat it as a nessecarry evil. This is one of the few sites I visit.
Thanks for the feedback.
First of all iam not a QP but use my AR daily so maybe i can help.
Your question might have already been answered but ill give my two cents, i own an AR-15 with a 16" barrel and love it. When i took an Advanced Combatives Course through a private co. many people there did not like that length. I personally love it even if it is about an inch and a half longer then most AR's floating around. Better accuracy and better shooting will come with a slightly longer barrel. Most of these people with the small barells such as the "kitty kat" and some others do it for looks when they were really designed for things like jumping out of a vehicle quicker etc.
On my weapon i have front rails with an Aimpoint Comp (that optic is what the Army issued to me overseas, had one in Afghanistan, no problems very tough) and a forward hand grip, the normal iron sight configuration is on there still with my Aimpoint pushed forward, so if that optic goes dead i can go iron.
I have taken three multiday contractor courses and saw the "gear queers" overseas too but i guess whatever floats there boat, i would say overall a forward hand grip and a nice red dot or magnified optic (depending on your mission) should be fine.
I think you will have alot of fun with that rifle.
Out
Thanks for the info everyone.
bberkly, I checked out those links and I really appreciate you taking the time to post those for me. I had no idea about the other forum as a resource.
Oh, and it is a complete lower receiver. I wouldn't have bought it otherwise. I'll hold my own with the best of them when it comes to pistols, but as I said earlier, rifles... LM GAS, that's about it.
I got the completed receiver for $250, it has the 6 postion stock, a two stage trigger (not sure what that does for me) and the houge grip. A friend in MT owns a small gun store and he odered it for a guy who was supposed to pick it up within 90 days and then never showed. Since the guy's deposite on it was non-refundable he just asked me to pay the balance.
Rock River/Bushmaster mentioned above are all good and the prices are reasonable. Colt charges an arm and a leg for their products. Definitely need some type of optics (Aim point....etc. I personally like the EOTEC on mine) of course you must have a good back-up set of iron sights. Rail System for your light you want to attach. Never bought anything from Gunsamerica.com but there is a large selection to choose from and the prices are good there. Most important you are choosing a Weapon you already know how to operate because of your Military background. My three principle Weapons I purchased after retiring were the three I used in the Army (M-4 Civilian version/Berretta Vertec and a M-24 SWS) Seen lots of guys put together fairly basic M-4 Systems only to get embarrassed on the Range because of pieces falling off (Lucky I have my own Range and no one was there to see my sights fall off....) Always use Lock-Tight when adding Accessories. An added trigger mechanism to make your trigger pull lighter can cost less then $50.00. Get away from the Military's extreme heavy trigger pull they seem to have on all their Weapons. Also there are all kinds of Compensators to reduce muzzle rise when firing. I am deployed now and can't remember the exact name of my Compensator but the difference between the Standard Military Compensator and mine is a great help. Being able to keep your sights on the threat while firing multiple shots makes a big difference. Anyone out there know of a good Web Sight with a selection of Compensators I am looking for another one.
I had no idea until very recently that the AR family of weapons could actually get any better than what the Corps issued me. That's why I was never interested in owning one. I mean, yeah you see the competition rigs in gun mags, but on a social workers salery, yeah right.
I am really stoked now thanks to all of the great feedback I've gotten. I've taken the time to look through the resources you've all been gracious enough to provide me with.
kgoerz, thanks especially for the tip about loctite, I would've never thought to use it. Now that I have the appropriate tools, finishing this project should be a breeze and a joy. As soon as I finish with it I will put up some pics on one of the many gun pics thread that pop up.