It's been a very long time waiting to order one of these, but I FINALLY bit the bullet and I can't wait.  I was on the original Shrike order list many, many years ago and went through a few years of waiting before pulling the plug.  Last weekend I went to a gun show and saw one of the FN M249's and loved it, but not for the price or the fact that it was semi.  So the next logical thing to do besides buying that?  Finally get that belt fed upper for my M16.  

Is there anything I need to know about adding this to my M16 that is not immediately obvious?  Do I need a different buffer?  I currently run a standard buffer and standard buttstock, my original M16 came in it's original 20" configuration and I decided to keep the buttstock on and add a 10.5 upper for play time.  

What about links, are the ARES links better than the surplus ones I can get on Gunbroker?  Is there anything special I need to know about linking my own ammo?  

Do these run reliably?  I havne't seen many malfunctions in my video search... just big smiles when shooting them.  

For those that haven't seen the keymod upper, here ya go:

I dont have a MCR upper yet but am planning to get one soon. The Wife said as soon as the house is paid off I can buy one, hopefully later this year

It should come with its own buffer, spring, spacer, bolt catch and other parts that must be swapped out to use. Ive heard if you use the parts they give you it greatly reduces issues with failures to feed and strip rounds from links. Its not the most reliable belt fed out there but for the price compared to a M249 or HK23 its hard to beat. Seems to scratch most peoples itch for a belt fed without breaking the bank. Be sure to post some pics or videos once you have it setup, im curious to see how it turns out.

For mine im thinking...
Atlas bipod
12" barrel with Trek-T suppressor
Aimpoint T2 or Specter Dr
Custom 150 round box mag (modified 200rd saw box mag)
and of course some light and lasers

I bought my links from a guy off sturm, 5k for $100 buck, they were LC links, Ares sells new LC links, I also bought new links off GB and I couldn't get them to work, they won't strip and I sold them to my buddy who has a HK.
You'll get a stiff spring and a spacer with your kit, I think a H2 buffer will work, I use a Vltor V5 system with a std V5 buffer, the ROF is a little fast.  

Oh and my linker works for food and free ammo to shoot

Do you plan on using a vertical grip? Reason I ask I have a atlas on a semi precision rifle, I tried it and didn't like it, I couldn't fold it back over the VG, I went with a Tango Down bipod

I've been wondering about what grip to use also.  I have several of the real (non-china) grippods and will try that first, but am looking for options.  Seems like you will need some type of grip because this thing is going to get hot!

I wasn't planning to use a vertical grip, was just going to put magpul rail covers on the side and bottom rails. I figured that combined with gloves would be sufficient to shield myself from the heat. But no you can't fold the atlas bipod backwards if you have a vertical grip, have to fold forwards or go with the tango like you did or a similar bipod that is wider.  Additionally you could grab the bipod itself, folded or unfolded, the maxwell or the Mag box and a lot of the shooting will likely be done in a probe or supported position.

You're going to need a different recoil spring.  The standard AR15/M16 rifle or carbine springs are both inadequate.  ARES sells carbine springs for their Shrike/MCR, but they don't sell a rifle spring.  You will need an MG34 spring for your rifle buffer tube, and you'll need to cut it down to somewhere between 29 and 35 loops.  I suppose the standard rifle buffer will work but IDK for sure as I've never tried that.  I run a kyn-shot hydraulic rifle buffer and my bud runs a Colt LMG hydraulic buffer on his and we're both pretty happy.  We both run cut-down MG34 springs.  The spring is very important because it has to strip the round out of the link, and that's no easy thing.

Start with a full length MG34 spring and a single round in a magazine.  If you can't get the buffer seated with the full length spring, then remove a few loops until you can install the buffer.  Shoot and see if the bolt locks back on the empty mag.  Remove loops in the spring until it reliably locks back on the last round in a magazine, and now your spring is tuned.

And for ammo, you'll pretty much need 5.56 ammo to make it run reliably.

For links - the Shrike/MCR can be very picky about links.  Some people lube their links - oil them.  This is effective, but now you have oily links and they attract dirt which isn't good for anything.  I've had success tumbling my new links in corn cob and car was overnight.  It knocks down the rough/textured parkerize finish on the links and smooths them up a bid.  I've thought about running links through my SS media thinking it would really knock down that parkerize finish, but haven't done it yet.  Also, a guy at Knob Creek sells link stretchers.  Word is that this solution works great but I haven't tried it yet.

I had to wet tumble my links, stretch and spray with silicone lube to get it to run right. Mine is the first release upper from about 2010. Used links are dirty and the grit increases friction. Clean links work better. Don't use links with holes in them. You'll know them when you see them.

I have a Vitor A5 system and that also helps.

For a rifle length buffer tube, you have to use the Ares carbine spring and their special rifle buffer spacer and an H2 buffer to get it to run right. Or DIY and cut as mentioned above.

I also have Mark Genovese's top cover insert to direct the bullet tip off of the aluminum part of the upper, which prevents digging in and jams reported by folks who shoot a lot.

I understand that the later uppers have improved feed trays which prevent the bullet tips from gouging the upper.

When it works it's great fun and a wonderful way to spend $5 a second.

Is this what you guys are talking about?  I have a H2 buffer but no spring. Upper arrives tomorrow and I can't fire it.   UGH.  Maybe it's time to add a Carbine stock and H2 buffer to the M16 and be done with it.  For $4K, I would have expected better info from ARES on this.  This forum is the only way I am finding any technical info on this.  

I thought the uppers came with a buffer, spring, modified bolt catch, 100 links and that spacer. You shouldn't need to order anything.

I do agree their technical data is very minimal. But hey that's whats so great about this forum, you can get an answer to just about anything.

BTW, these are the modified mag boxes I was referring to in my first post.

same guy makes side mount nutsacks as well, I have both.....but I prefer the uptight saw box, it looks 100x cooler

How many rounds do you get in your uptight box?

ive heard anywhere from 150-180 rounds

Tom Cassidy told me 180, I tried 180 a couple times and it jammed both times, so I keep it at 150 and haven't had any issues...

My Shrike came with a pretty extensive owner's manual.

where do you get those?

source? happen to have a link to a website?

where can I get that plastic insert for the top cover?

any idea who that seller is and whether he has a website?

The uptight SAW boxes were made by a guy named Tom Cassidy.  He sells them on subguns, but I know he has been looking to retire for awhile now, so I would grab one sooner than later.

http://www.subguns.com/classifieds/index.cgi?db=nfapartsandaccys&website=&language=&session_key=&search_and_display_db_button=on&results_format=long&db_id=5492&query=retrieval

The link stretcher tool is sold by Terry Rood, he also advertises on subguns.

http://www.subguns.com/classifieds/index.cgi?db=nfapartsandaccys&website=&language=&session_key=&search_and_display_db_button=on&results_format=long&db_id=5494&query=retrieval

Mark Genovese is the guy who makes the top cover inserts.   He doesn’t have a website but you can reach him at  mauiarms at maui dot net.  You will have to send him a money order to Hawaii where he lives.

Hope this helps and did you finally get your Shrike?

yes, got my Shrike, just waiting on the replacement bolt carrier

thanks for the tips, and let's together and fire our Shrikes and M60E4s soon

I've been on the fence post to buy a top cover insert, do you have one?

Glad to hear you finally got it.  

Definitely need to see about getting a shoot together this fall once it cools off.

I do.

Whether it does anything, I am not sure....    

I definitely had wear on my receiver but I think most of it was with the Gen1 aluminum feed tray.  I replaced it with a later gen steel tray and the wear seemed to subside. I figured it was  inexpensive insurance against any additional receiver wear.  The block is  $100 and a replacement receiver is something around $2K.  

I have heard rumors that the latest gen Shrikes/MCRs now have a metal insert in the receiver to prevent the this wear point on the receiver.

If you don't mind what did it cost and where did you get it from?

The top cover feed ramp insert is $100 plus 10  to 15 for shipping.  

They are made by Mark Genovese in Hawaii.  You need to email him at mauiarms @ maui  dot  net   to make sure they are in stock and to get the address to send payment.

There is a steel insert in the newest gen of shrikes....
The plastic feed ramp isnt as vital anymore, but i still like it.

Your eventually going to wear out your receiver end of story... but with how much the ammo costs the $1000 aries will charge you to replace it isnt really that big of a deal.

My plastic feed ramp has serious wear, and now it comes loose and moves around.i've been running withput it. I just recsntly shimmed it back in there. I guess i need to buy a new one.

So much for the "space age mateial" there made out of......

http://s1339.photobucket.com/user/MGnoob/media/Mobile%20Uploads/20160525_190445_zpsbsnniafv.jpg.html?sort=3&o=3