AR Mismatched uppers and lower

[SalchaketJoe]

Anyone have a problem, or rather a beef with them? My last AR was a STAG upper and DPMS lower. Functioned perfectly and was at least $200 less then buying a complete rifle. My latest, see http://www.thehighroad.org/showthread.php?p=5961174#post5961174
saved me probably $300. Again, dont understand paying more for the matching upper and lower.

That being said, should shoot it tomorrow, will let you know how it does. The two went together like bacon (not that turkey bacon crap) and eggs.

Quik range report. Could only fire 70 rounds as I had to pick up the wife. Functioned as advertised. Accuracy @ 50yards with red dot and me off my elbow off the bench, 1.5 inches. Ammo was Hornady TAP training ammo. Steel cased, 55gr FMJ. Also Prvi partison (spelling) 55gr soft points. The POI with the Prvi was 1.5inches higher than the other zero.

MBUS: Windage was a little tight. It being plastic I was hesitant to go gorilla on it. Managed all right, got it to turn. Doesnt have very defined clicks. Overall, for what it is, am satisfied. Would recommend.

Vortex Red dot: The light is a little dim on maximum setting in direct sunlight. Not sure, but would guess its a 3MOA dot. Positive click adjustment. Made one large correction to bring the group up about 8 inches. Then a few smaller ones. Responded well. Forgot to bring the screw on 2x magnifier.

Plan to put 200 rounds through it tomorrow. I am happy so far with the accuracy. For what it is, that is fine. Want to move out to 100 and 200 yards and see what I can do.

 

[PT1911]

that is the beauty of an AR... interchangeability..... no problem with that...

 

[W L Johnson]

They don't call them the Lego of the gun world for nothing. Enjoy.

 

[12131]

Franken ARs are just fine with me.

 

[12131]

And, buying a complete AR is always more expensive than buying the upper and lower separately, for any particular model.

 

[f4t9r]

no problem here

 

[Z-Michigan]

I've played with a couple frankenrifles and so far all have worked. I did recently discover a very tight fit between one combination of a lower and upper I had. I'm guessing it was due to "tolerance stacking," i.e. the parts were built at opposite ends of the allowed range for distance between the pins.

And, buying a complete AR is always more expensive than buying the upper and lower separately, for any particular model.

Usually, not always. There are some deals recently (post-shortage) that are cheaper than I could assemble the same rifle for from halves.

And remember, the savings is mostly because the manufacturer has to pay federal excise tax on the "firearm," which is the whole rifle if you buy it that way, or just the lower if buy a lower separately.

 

[dispatch55126]

I did recently discover a very tight fit between one combination of a lower and upper I had. I'm guessing it was due to "tolerance stacking," i.e. the parts were built at opposite ends of the allowed range for distance between the pins.

What was the build?

 

[kamagong]

No problem here. Apart from an aesthetics viewpoint, a mismatched AR can be just as good as any factory rifle. That is assuming you use good parts and not try to cut any corners of course.

 

[Runningman]

Anyone have a problem, or rather a beef with them?

Not really.... but you should keep in mind that typically Franken ARs can be harder to much harder to sell, depending on the brands involved. Resale value is not usually as great as same brand upper and lowers.

 

[briansmithwins]

Not really.... but you should keep in mind that typically Franken ARs can be harder to much harder to sell, depending on the brands involved. Resale value is not usually as great as same brand upper and lowers.

That's why you strip it back down and sell the parts as parts. You get more money that way too!

BSW

 

[Z-Michigan]

What was the build?

Ameetec lower and CMMG upper. The upper works fine on a Charles Daly lower and the lower has been fine with a Bushmaster upper. YMMV!

 

[RP88]

my first AR was a franken AR

it worked fine.

My new one is a CMMG upper with a CMMG lower, a CMMG stock, a Stag parts kit, a BCM carrier, and an LMT bolt - and it works great.

 

[BsChoy]

I just re-frankengunned (sp?) my ar for a second time. Went from a Del-Ton complete 20" upper to a M1S 16" M4 config with a boatload of different parts and it shoots juuuuuust fine

 

[PandaBearBG]

No problems here, as long as the lower is quality made, it doesn't do much but sit there, holding stuff.

 

[HOLY DIVER]

i recently put a model 1 6.8 upper on a rogio lower ....perfect fit

 

[3pairs12]

Crap my was about 3 or 4 different manufactures. I consider tham "custom".

 

[jkingrph]

What's the big deal, they are made to standards to be interchangable.

I recently bought an Alexander Arms upper in 6.5 Grendel and put in on one of my Colt lowers for a while.

I have always liked long rather heavy guns, with long stocks because of my height and my wife finds them difficult to shoot so I decided to do something about it.

First I picked up a stripped Rock River lower, actually three, and have completed one for the previously mentioned Grendel, adding a Magpul CRS stock, making it look somewhat like a space gun, but hey, it fits.

The other two lowers are for a couple of mid length carbines, I am waiting on buffer tubes to complete them with collasable stocks, one is to be a .223 for the wife the other a 6.5 Grendel for me. The barrel suppliers are very reputable and had deals on upper receivers so I took theirs and will be assembling them as I want. My wife's barrel, a 16" stainless mid length came in yesterday and the upper they supplied is not stamped with a makers name at all. I has a marking that I recognize as being the major supplier of forgings for these parts so all is good. White Oak Armament, the supplier has only top quality parts, being a builder of guns primarily for target competition, ie, NRA highpower type shooting, not the tactical games.
They have a reputation for quality and are not one of the big makers or suppliers.

Bottom line is pick up quality parts, assemble properly and accruately, and you can have as good or a better gun than supplied by a maker of complete guns, for the same or less money. The way I am building mine will not not be less expensive, but will be top quality with far better than average barrels and triggers from the start, which in the long run will be less costly than replacing parts later to upgrade.

 

[yosarian]

My frankengun has almost a 1000 trouble free rnds throough her.No,no problems with them at all.

 

[browningguy]

I don't have any matched AR's. I have 2 RRA and one DPMS lower built with the triggers I wanted in them, with a DPMS, Alexander Arms and a custom 6x45 upper. One RRA has the RRA 2 stage match trigger, the other a McCormick 2 stage, and the DPMS has a McCormick single stage trigger that I shoot the .50 Beowulf upper on.

 

[1time]

I have a Smith lower with a CMMG mid upper, and a Smith lower with a Bushmaster upper. I don't care what resale is because I don't plan on selling them. They shoot fine and are dead reliable. I shoot them both more than I do my complete Colt.

 

[pearidge]

Don't sell, gather more

 

[Zach S]

The only problem is the resale value. Even if you use a top-shelf upper like Noveske, its still "just a DPMS" if they made the lower.

However, I don't have any top shelf uppers, and dont plan on selling any of my mid-tier ARs.

Two (of my three ARs) are mismatched. Actually, even the matched AR is sort of mismatched. Its a RRA 9mm upper on a RRA .223 lower.

 

[mljdeckard]

I think that there is a bit of pressure within the industry to not be 'that gun' that everyone knows you won't be able to use EVERY part and accessory on the planet for it. An example that comes to mind is Colt's mismatched pins. Now everyone knows, "Any upper will fit any lower EXCEPT A COLT." No one wants to be nudged to the bottom of the list whenever anyone is looking for mix and match setups.

 

[MCMXI]

AR Mismatched uppers and lower
Anyone have a problem, or rather a beef with them?

No, not at all. However, I bought a POF P-415 Gen III stripped lower today for the simple reason that I want a complete POF AR-15 for aesthetic purposes. I've been running a POF P-415 upper on a Bushmaster lower for months now with zero issues, but after buying a complete POF P-308 SPR recently, I decided that I want the AR-15 to match as well. I'm not sure what I'll do with the Bushmaster lower but I was thinking about putting together a rifle that's legal for National High Power competition. The Gen III lower shown below has an ambidextrous slide release which I like. It's machined from a billet so it comes with an integral trigger guard which adds stiffness but other than that it's a luxury item. I doubt I'll see any difference in performance compared to the Bushmaster lower but who knows.