AR 15 Conversion Kits – Best 5 Types You Should Own

AR 15 Conversion Kits Top Five Product Review

AR 15 Conversion Kits
AR 15 Conversion Kits – Best 5 You Should Own

AmmoLand Gun News

USA –-(Ammoland.com)- AR-15s are modular, hence the AR 15 Conversion Kits.

Push out the takedown and pivot pins and remove the upper – it contains the barrel and the matching bolt carrier group, the charging handle and the gas system.

If you’ve zeroed an optic or scope, it comes with the upper, too. Replace the original upper assembly with a different one; push the two pins back into place, and voila! You’ve got a different gun.

Standard 5.56mm lowers can’t accept larger .308 uppers, and vice versa. But there are plenty of AR 15 Conversion Kits in all sorts of calibers that will work perfectly with standard 5.56 lowers, and the lineup seems to expand all the time. There are many complete upper assemblies available that are literally “plug and play” on any standard AR lower assembly.

And if you’re comfortable with a few basic tools – like a vise and a barrel nut wrench – you can easily build up your own stable of extra AR-15 complete upper assemblies. Quality suppliers like Brownells have all the barrels, uppers, handguards, bolt carrier groups and associated tools you’d need.

Why would anyone go to the trouble of getting a bunch of uppers to go on just one AR-15 lower?

Magpul BAD Lever
Magpul BAD Lever

Think of it this way. You’ve spent time and money getting the exactly the trigger you want, and the best stock that fits you perfectly. Maybe you’ve added a Magpul BAD Lever, and the ideal pistol grip for your hand. Why should you give all that up just because you want to do a different kind of shooting, at a different distance?

The good news is that you don’t have to, at least not if you get a spare complete upper assembly or three. That way, you can use the same gun for everything from plinking soda cans on the family farm, to sniping steel targets way out there, to hammering feral hogs in thick brush, just by pushing two pins and swapping uppers.

I’ve put together a list of complete AR 15 Conversion Kits assemblies every Black Rifle owner should consider owning:

  • A big bore kit like the 458 SOCOM AR 15 Conversion Kit.
  • A 6.5 Grendel AR 15 Conversion Kits.
  • A 300 AAC Blackout AR 15 Conversion Kits.
  • A 22 LR AR 15 Conversion Kit.
  • A Varmint or Precision AR-15 Upper Kit.

I’m basing this list on the assumption that you’ve already got an AR-15, most likely a 16-inch carbine in 5.56. And if you don’t yet, now is the time to buy, as there are tons of bargains out there on 16-inch carbine style ARs in 5.56.

But here’s my list of the Top 5 AR-15 Uppers every Black Rifle shooter should think about owning.

5) A Big Bore AR 15 Conversion Kits :

458 SOCOM Ar-15 Upper
458 SOCOM AR 15 Conversion Kits

As good as the 5.56 cartridge is, there are some things it just doesn’t do that well. Delivering whomper-stomper hits on big, tough game animals like feral hogs are one of those things. There are several different big bore cartridges out there designed to fit through an AR-15 magwell, and it seems like more are developed by creative wildcatters every year.

Some of the really popular big bore AR cartridges include .450 Bushmaster, .458 SOCOM and .50 Beowulf. All of them throw big fat bullets at relatively slow velocities and are devastating at close range. If you want readily-available factory ammo, .450 Bushmaster might be the best bet. If you handload, .458 SOCOM probably gives you the most versatility, as it uses rifle bullets available in a wide range of weights and styles – as heavy as 600 grains if you want.

And if you really must have a caliber that starts with a 5, and is named after an epic hero, then .50 Beowulf is the only choice.

Cross Machine Tool Co - AR-15 458 SOCOM Billet Upper Receiver
Cross Machine Tool Co – AR-15 458 SOCOM Billet Upper Receiver

Perhaps the best aspect of adding a Big Bore AR 15 Conversion Kits is that you can typically use standard 5.56 magazines, although Bushmaster does add a special “single stack” follower and springs to standard 20-rd magazines specifically for use with .450 Bushmaster ammo. Any of these cartridges will give your AR-15 performance similar to the venerated 45-70 at close range, in a lightweight, semi-auto package. The possibilities are endless.

If you decide to build your own Big Bore AR 15 Conversion Kits assembly, be sure to either enlarge the ejection port, or get an upper with an ejection port specially made to accommodate the big fat cartridge cases.

4) A 6.5 Grendel AR 15 Conversion Kits :

6.5 Grendel Ammunition
6.5 Grendel Ammunition: 6.5mm Grendel round showing variety of bullets 144 gr (9.3 g) to 90 gr (5.8 g)

The 6.5 Grendel is an amazing cartridge. It uses 6.5mm bullets, known for having good sectional density and relatively high ballistic coefficients – which means they fly very well, even in stiff crosswinds. The Grendel gives performance similar to, if not better in some ways as the .308, but in a cartridge that can fit inside a standard AR-15 lower.

C-Products AR-15 6.5 Grendel Magazines
C-Products AR-15 6.5 Grendel Magazines:

Just a few years ago the 6.5 Grendel’s creator, Bill Alexander, opened the door for even more manufacturers to crank out ammo, parts and barrels with the name “Grendel” on them.

Not surprisingly, Alexander also first developed the .50 Beowulf, and took the Grendel’s name from the same Old English saga.

Unlike the Big Bore uppers, a 6.5 Grendel will require a magazine specially shaped for that round. For reaching way out there with a standard-sized AR-15, it’s hard to beat the 6.5 Grendel.

Be sure to add a good-quality scope and some nice rings to complete the package.

3) 300 AAC Blackout AR 15 Conversion Kits :

300 aac blackout vs 223
300 aac blackout vs 223

The 300 AAC Blackout cartridge gives performance very similar to the 7.62×39, but in a cartridge that works perfectly with standard AR-15 bolts, magazines and lowers. You can convert any standard 5.56 AR-15 to .300 AAC Blackout by merely changing only the barrel. Of course, if you don’t want to mess with taking apart your current upper, you can just drop a complete 300 AAC Blackout AR 15 Conversion Kits onto your lower.

Why not go with an AR-15 upper in 7.62×39 in the first place? You can use less-expensive steel-cased ammo in a 7.62×39, but there are tradeoffs. Typically, you’ll also need to put in an extra-power hammer spring to help reliably ignite the sometimes-harder primers found on cheap, foreign-made steel cased ammo. Many shooters also add in special firing pins to help set off primers in less-expensive steel cased ammo.

Finally, you must have specially-shaped mags for a 7.62×39 AR. But the 300 AAC Blackout uses the standard 5.56 mags that you probably already have in good supply.

Advanced Armament - AR-15 Upper Receivers in 300 Blackout
Advanced Armament – AR 15 Conversion Kits Receivers in 300 Blackout

Where the 300 AAC Blackout really shines is with sub-sonic loads combined with a suppressor. Suppressed, it is remarkably quiet, has little recoil, but still lets you thump targets with bullets that weigh up to 220 grains. If you live in a state that allows suppressor ownership (congratulations, Minnesota!), you really should consider getting an upper in .300 AAC Blackout with a suppressor-ready muzzle device.

2) 22 LR AR 15 Conversion Kits :

Yes, I know we’re still in a .22 LR drought, but there seem to be signs of it easing. Maybe. Even with .22 LR hard to come by in some locales, a dedicated .22 LR upper makes a lot of sense for AR-15 owners.

You can get conversion kits that let you shoot .22 LR through any standard 5.56 AR-15, just by swapping out the bolt and carrier group and using a special magazine. And these kits are almost always less-expensive compared to dedicated .22 LR AR 15 Conversion Kits. Many shooters get these kits, and enjoy them a lot. But there are some reasons why you might want to consider a dedicated .22 LR upper.

First, dedicated .22 LR uppers typically have barrels specifically rifled to work with slower, lighter, all-lead projectiles fired from rimfire cartridges – something like a 1-16 twist. The twist rate in your 5.56 AR-15’s barrel is intended for 55 grain, or heavier, jacketed bullets moving at much faster speeds. The slower twist rate often results in better accuracy from a dedicated .22 LR upper compared to a conversion kit.

Tactical Solutions - AR-15 .22LR M4 Upper Receivers
Tactical Solutions – AR-15 .22LR M4 AR 15 Conversion Kits

Second, true .22 LR uppers are blowback, and don’t need a gas block or gas tube, and are thus often lighter. Your 5.56 AR still wears its gas block and gas system parts when you swap out just a bolt carrier group and magazine to convert to .22 LR.

More accurate and lighter easily translate into more fun, which are both important, especially if you’re using your .22 LR upper to help introduce young or new shooters to the game.

1) A Varmint or Precision AR-15 Upper in .223/5.56

Mk 12 Special Purpose Rifle
Mk 12 Special Purpose Rifle

Let’s say you have a 16-inch AR carbine, and you’ve carefully selected the stock, trigger and pistol grip that suit you best. You aren’t interested in having to worry about another caliber, but would like to be able to reach out a little farther and a little more precisely.

Your best bet might be to invest in a dedicated varmint or precision AR 15 Conversion Kits, especially one with a high-quality scope mounted.

Here’s how that combination could work. The 16-inch carbine upper is lightweight and fast handling, especially if you put a red dot or similar electronic sight atop it. With that rig, you can get quick hits inside of 300-yards, exactly what you need for self-defense, many types of action shooting sports and certain types of hunting.

But what if you could convert the same gun into a tack driver in less than 60 seconds, and then smack small targets and varmints, out to 500 yards, or maybe even farther?

If you’ve got an upper with a free-float handguard, bipod, long-range scope and a heavy target barrel – especially one with twist rates optimized for match-grade ammo tipped with bullets up to 77 grains , you can – provided you develop your shooting skills enough.

DPMS AR-15 TAC2 Upper Receiver Assembly
DPMS AR-15 TAC2 Upper Receiver Assembly

It’s an idea that even the US military likes, with the various versions of the “DMR,” or Mk 12 Special Purpose Rifle sharing several of those features. Of course, just slapping a free-float, heavy-barrel AR 15 Conversion Kits onto your carbine lower will not magically transform it into a Mk 12 SPR, but it can give you some real upgrades when it comes to longer-range performance.

New Take On Old Saw

There’s an old cliché out there that goes something like this, “Beware the man with only one gun. He probably knows how to use it.”

But if that “one gun” is an AR-15, it can quickly turn into a whole lot of different guns, just by pushing out two little pins, slapping on a new AR 15 Conversion Kits assembly, and pushing those two little pins back into place.

 

Thomas Conroy is a firearms aficionado and writer who lives in the Midwest.


AmmoLand Editor Comments:  This article was updated to reflect changes in product improvements/availability on 07/13/2017.

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k_minton
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Advanced Armament – AR 15 Conversion Kits Receivers in 300 Blackout
Where the 300 AAC Blackout really shines is with sub-sonic loads combined with a suppressor”
I do not agree.

weasle94
Guest
weasle94

will a 450 Marlin blow my freaking head off if it is shot out of my 450 bushmaster AR 15?

Craig
Guest
Craig

YES!

Brandon
Guest
Brandon

I’ve been thinking about buying a jig and a 80% lower and finishing it my self. This would be my first attempt at a build and my end goal is to build a .458 socom by buying all the parts and put it all together pieces by pieces. Do you have any suggestion, recommendations and or places to find more info for a first time builder?

Thanks B

Jim in Conroe
Guest
Jim in Conroe

Brownells has a great set of videos that will take you step by step through building an AR platform firearm. They also have an interactive configurator that will allow you to put together your virtual firearm and try different modular components like forearms, stocks, pistol grips, etc.

Jonathan
Guest
Jonathan

What if its a pistol build you’re looking to convert? Say a .300 Blackout AR Pistol, 10.5″ barrel, pistol brace… etc. Swap the upper out to a 5.56, 6.5 Grendel, or even .50 Beowulf. Other than needing the mags for the 6.5; stock, tube and spring, and it should be good to go correct?

Ed Bradley
Guest
Ed Bradley

I would like to see someone do with the .50 beowulf they did with the 6.5 grendel vs 6.5 creedmoor & a big .50 on a larger AR10 format

Kevin
Guest
Kevin

So i want to build a .300 blk sbr 10.5″ barreled ar-15 and i dont want to buy a complete upper id rather buy each part and put it together myself so i can custumize it how i want it. Do i need to buy a specific upper reciever or can i use my extra (bro spec15 5.56 upper) and just buy a .300 blk barrel??? Also do you have to use any other parts that are .300 blk specific?

Mark
Guest
Mark

You’ll also need a bolt carrier group. I just did a new upper 5 second switch uses the same magazines and functions well. More work if you switch the barrel and BCG using all the rest but that works as well.

James
Guest
James

I have a complete ar15 in 223, would I be able to put a 204 upper on it and fire it with no problems?

Juan
Guest
Juan

Yes, yes you can! And if you get one with a 24″ varmint weight barrel you’ll be shooting those 40grain bullets to almost 4,000 fps!

donfranko
Guest
donfranko

300 BLK……..the best of both worlds. The coming fights will not be in mile long empty fields, but in cities, house to house, short range, a block or two. 300 BLK has the knockdown power of the 308, and ease of use of the AR15. It just doesn’t get any better.

Carl
Guest
Carl

won’t do any good if you cant find ammo, rather prefer a cartridge in use by the military and about everyone else easy to find

Ernie Pounders
Guest
Ernie Pounders

Can you covert to a 6.5 Creedmoor? Ruger 556c AR15

J. Heath
Guest
J. Heath

Sorry no. Creedmoor is too long for AR 15 mag well. It requires an AR 10.

Michael Porter
Guest
Michael Porter

I’m sorry about the spelling

Michael Porter
Guest
Michael Porter

THE more get know about ar 15 more i love i havegas piston from andemy arms work purfect ,a 300 blackout ak ar i’m thing about building grendel for the hell of it HAVE WITH YOUR AR ALL PACLBE

Jon
Guest
Jon

Thanks again Mr. Walker for the info the reason I was even considering a bump stock because I ran across it in a you tube video and it looked like a lot of fun, Mr. M I was shooting for accuracy but seen this bumpfire and looked like some fun once in a while since our government don’t allow auto fire guns without a permit and my CPL don’t count (sad) but with that said a chrome lined barrel wouldn’t be a bad idea any suggestions for a M&P -15 smith and Wesson gun I picked up about 5 yrs.… Read more »

Willard Walker
Guest
Willard Walker

I think I would still find a 16 or 18 inch FNH cold hammer forged double chrome lined barrel. Their accuracy is very good my 16 inch and 20 inch barrels both shoe well under 2 and a half inches with iron sites consistently at 100 yard. Scoped I’m averaging well below – it depends on the day best groups are about .42 with the 20 inch and about .53 with the 16. I think when you comes to a grill them lined barrel the FNH barrels are hard to beatand give maximum life. If you’re looking for true accuracy… Read more »

Jim in Conroe
Guest
Jim in Conroe

No mention of the 450 Bushmaster, probably more popular than any of the conversions mentioned. Also, some of the suggested conversions wouldn’t allowed to work due to magazine / mag well incompatibty issues related to using a ,223 / 5.56 lower.

Jim in Conroe
Guest
Jim in Conroe

The 450 BM gets a mention in the first section on big bore AR’s. He fails to mention that it can be reloaded in a wide variety of bullet types and weights from 180 , to 325, though the factory 250 gr and the 225 FTX seem to be the most popular along with XPB’s for hunting. There is an excellent forum at http://450bushmaster.net.

Fal Phil
Guest
Fal Phil

More popular? Seriously??

I have seen literally thousands of AR 15s. I have seen many 300 Whisper/AAC Blackouts. I have seen hundreds of 22LRs. I have seen a couple dozen Grendels, and a couple of 458 Socoms. I have even seen a half dozen 7.62×25 conversions. I have NEVER seen a 450 Bushmaster AR15.

rappini
Guest
rappini

Great article and posts, thanks

Jon
Guest
Jon

Does anyone know what kind of barrel to use for the bumpfire and a 100 round mag.

Willard Walker
Guest
Willard Walker

Use a Cold hammer forged FNH doudle chrome lined barrel. Its also refered to as their Machine gun steel barrel. It is the same barrel found on the military issued rifle it just has the FNH logo instead of the manufacture number stamped on the barrel. You can pick up the barrel or the complete upper at Palmento State Armory about the cheepest anywhere if you are willing to wait. This barrel will provide the best life you will find in my experience. watch the temp of the rifle doing mag dumps or you will blow your gas tube out.… Read more »

Jon
Guest
Jon

Thanks Mr Walker for the info I appreciate your email back

Jon

m
Guest
m

Haha, yeah this was an interesting reply from Mr. Walker. I was just going to say get the cheapest chromelined one you can find (or several of them) and go have fun. I imagine you’re not Shooting for accuracy with a bump fire stock and all, so as long as you don’t over heat it to where it warps or has other permanent danger issues, then keep on keeping on. But I’d say follow his 2 cents rather than mine…

Ron H
Guest
Ron H

The little cartoon book the Army called a field manual that was issued with the A1’s stressed under sustained fire no more than 15 rounds per minute to prevent damage to the barrel.
That is not a “rock and roll” number.

Willard Walker
Guest
Willard Walker

The army also wanted each barrel to see a minimum round count of 25 to 30 thousand rounds per barrel/weapon. This was proven it to be unrealistic so was their 15 rounds per minute. The stated manual was written by bean counters that only had a cursory knowledge of the rifle that had experienced major issues in early life due to the development of the 5.56×45 cartridge over the .223 the rifle was initially developed fire. Hence major improvements and than the A2. 15 rounds per minute will not damage a barrel. 60 rounds in a minute will not damage… Read more »

NRAR15
Guest
NRAR15

Bump fire stocks are now illegal to own and your a jackass if you think you need one. plus it takes talent to use one correctly. im sure if your looking for one you have little to no talent in firearms handling anyway. I can put more rounds in center mass in semi auto than you or anyone can with a bumpstock.. so save your 500dollars and 10years of your freedom and buy a real AR and leave it the way it comes and you may survive a firefight.

None
Member
None

Some people live in the country and just want to shoot can and stuff for fun and not take the center mass so serious, and to hell with the goverment encroaching on your 2A unless you like listening to them after all they are your friends right
Have fun and blast away

David Christensen
Guest
David Christensen

All of my 5.56 AR rifles & mags are black. All of my NON-.556 AR guns & matching magas are a different color, like Cerakote Burnt Bronze, or Magpul FDE. That way I don’t end up trying to load a 458 SOCOM round in a 6.5 Grendel riffle, etc.,

John
Guest
John

I do the same thing…. Beats confusion. Anything non standard gets other than black furniture. It’s saved the day more than once……

David Christensen
Guest
David Christensen

It should be mentioned that a .300 Blackout round will chamber in a .556 upper, with disastrous consequences! Be careful!!!!

fitter it out
Guest
fitter it out

That was a good article. I didn’t know that with some different chamberings magazine mods would be necessary. And why do only half of my replies show up because I am not rude or hate on people or even cuss like some of the folks on here do I’m just wondering

kevin boisvert
Guest
kevin boisvert

so as i have read my i have a multi caliber smith and wesson OR edition, so if i read everything correctly all i need to do is get and upper for 300 blackout and im all set..

Allen
Guest
Allen

All you need is a 300 blackout barrel. But yes. If you go ahead and make it easy on yourself and just buy a complete 300 blk upper already put together then yes. You’ll immediately be shooting 300 blk. But be VERY VERY CAREFUL not to accidentally try and shoot a 223/556 in your blackout upper. That could be very very bad. I suggest only taking either the 300 or the 223 out at a time. Never take both to the range. And I would even mark your magazines somehow as not to accidentally mix them up. I personally use… Read more »

SSG B
Guest
SSG B

You have it backwards ALLEN. What you never want to do is shoot a .330 BLK in a .556/.223 because certain .300 BLK rounds will chamber in .556 rifle. It may fire…once but a .300 BLK bullet will absolutely not go through a .556 barrel without catastrophic failure. 556 will not chamber in .300 BLK barrel because .556 is a much longer round.

Willard Walker
Guest
Willard Walker

A instructor in in San Diego had a student that had very bad day last summer due to his inattentiveness And neglect. He was teaching a student who put a mag of 110gr .300 blackout in a .556. the rifle fired blowing the upper and the guys right forearm all to hell. The student was a lefty and he cought most of the blast mid right lower arm. How the instructor missed it remains unknown but he must have been paying attention to something else. Why he had two different calibers rifles out in the first place is also unknown… Read more »

Allen Johnson
Guest
Allen Johnson

I may have it backwards sir. My point was to BE CAREFUL. Do not take 300blk and 223 out at the same time. There is no need to. It just makes sense to keep your range time to one predetermined caliber for obvious reasons. But. Thank you staff sargeant for setting me straight.

Les
Guest
Les

Stupid question on my part. I have a colt at-15 in .223. Can I just swap out a 5.56 barrel to shoot 5.56 or is there some other changes I need to make?

Allen
Guest
Allen

No sir. Just swap the barrel. That’s it. Your good to go!

Viscount
Guest
Viscount

Be careful. Some 5.56 ammo fires at higher pressure than the .223 your Colt was designed for. Double and then triple check that your Colt upper can handle 5.56 pressure.

Or get a complete 5.56 upper.

Ron H
Guest
Ron H

If your Ar15 is original Colt product, check the barrel behind the muzzle and front sight. It will be marked with the cal. the barrel is rated for, the rate of twist, and barrel contour/weight. I own 8 original Colt AR’s and they all have these markings.

John C
Guest
John C

Were can I find a 50. Beowulf barrel ? I’ve built a few ARs and would like to build one in 50 caliber Beowulf .

John Katter
Guest
John Katter

There is a new feature of the internet that allows you to search for such things by simply entering the words you want to search for into a little box and hitting the enter key. Give it a whirl. It’s http://www.google.com. You’re welcome.

Do or Die
Guest
Do or Die

“whatta ***dick”

Fitter it out
Guest
Fitter it out

You will need another upper receiver to because the ejection port is enlarged quite a bit the ones I’ve seen don’t have room for a dust cover they are pretty large casings

Jim
Guest
Jim

Guns are fun. Me likey!

Logan
Guest
Logan

What do I need in order to convert my .233/5.56 to a 6.5 Grendel? Complete upper plus mag?

Allen
Guest
Allen

Yes. You’ll need barrel. Bolt. Magazines.

Hector Medrano
Guest
Hector Medrano

Hi, Kinda new to this. I have a .22 Mosberg would like to know if I’m able to upgrade to a bigger caliber and what parts I would need.
Thanks for any input

Trent
Guest
Trent

No you can not. If you had something along the lines of the Smith & Wesson M&P15-22, yes. However, that’s not what you have. You have a designed “AR” in 22LR. Good gun, keep it fed. But if you want something you can convert, have to get the real deal.

Wild Bill
Guest
Wild Bill

Welcome to the forum, Hector!

thomas brown
Guest
thomas brown

What would it take to convert supper .17 to ar platform i would like to do just that small fast round low coast ammo .or am i just dumb .?

WILL GARNER
Guest
WILL GARNER

i have a bushmaster 5.56/223 you are saying that if i buy 300 blackout kit that it will switch out with no need to buy anything else??

Yok
Guest
Yok

All you need is the 300 blk out upper for your bushmaster. Mags are interchangeable since 300 blkout uses the 5.56/.223 casing. I’d encourage you to steup a trust and get a SBR and the 9″ barrel like I did.

Buffer & tube springs you’ll want jp or spikes. For extra tweaking.

Austin
Guest
Austin

I’m curious now. Would it be possible to have an upper fit for .22×.250? That would be the ultimate varmint rifle.

Trent
Guest
Trent

Don’t plan on it. Nemo has an AR in 300 win Mag. It’s completely proprietary, so it’d be the same style of design. If you want one, you’re looking 7k if it comes to production. Even more now considering it’d be a completely custom rifle. And there’s a much better caliber. See if you can find some info on the 260 Dingo. A company in my town makes the bolt guns for it. Just shy of 4k fps. They’re getting jackets to shred past 3975fps. They’ve shot coyotes at 425 that took lungs out the other side, and one at… Read more »

Sumit
Guest
Sumit

Hey isnt the ar15 in .300 win mag the falkor petra?

fitter it out
Guest
fitter it out

I do believe Falcor and Nemo are the only two making them I very well might be wrong but I have seen the Nemo in person but have only heard of Falcor making one I also seen a Nemo in 338 Lapua the last time I went to my local shop and almost died when I seen the price tag

James T Kirk
Guest
James T Kirk

Noreen also makes one.

Ron H
Guest
Ron H

Nosler has come out with its Nosler 22 round. The case has 25% greater capacity than .223. It delivers 30% more energy and is nearly 300 fps faster than a 223. Switch to a 6.8 Remington SPC magazine along with a simple 22 Nosler barrel swap and the transformation is complete.

Ruben
Guest
Ruben

Can i just buy a complete 300 blackout upper and install it on a 5.56 complete lower and have a working AR 15? I’m looking in to getting my first AR. Thinking of buying separate pieces and then just put them together. Thank you

AJ
Guest
AJ

Absolutely. That’s exactly right.

Yok
Guest
Yok

Mil spec stock or commercial? (For 300 blk out)

Ken
Guest
Ken

I have a question, I want to change out the upper 300blk to a 223. . Do I need to change out the buffer spring too?

AJ
Guest
AJ

No. It’ll be fine.

Pootie
Guest
Pootie

Conversion kits r fo shizzle my nizzle!

Brian Nalls
Guest
Brian Nalls

I like guns

Thomas Fowler
Guest
Thomas Fowler

Enjoyed the article…well thought out.

Does anyone make a .45 ACP upper?

Thank you.

Thomas Fowler
Guest
Thomas Fowler

I mention this as an old Thompson shooter…we got a lot more velocity from the .45 ACP than from the five inch 1911 barrels. This would make me a great farm gun for pests and….whatever.

A wringing out of such a piece, with the writer shooting at fifty yards, minimum, would be outstanding. Far more practical, for my farm, than the .223…

GlassWolf
Guest
GlassWolf

.45 ACP and subsonic .300 AAC have nearly identical specs if you compare them, with the .300 giving you better coefficient and a lot more power in the supersonic range as well.

.45 ACP – 230 gr with a muzzle velocity ~830-1050fps
sub .300BLK – 180-220 gr with muzzle velocity ~950-1050fps
super .300AAC ~2000-2300+fps

Trent
Guest
Trent

Yea, but price 45 ACP vs 300 Blackout. Here in east Tennessee, 45 would be a hell of a lot cheaper.

JAMES SETO
Guest
JAMES SETO

http://www.D3LLC.com builds complete 45ACP uppers for around $750 and also offers an integral suppressed 45ACP upper for you NFA guys for around $2,800..

Paul Gavinger
Guest
Paul Gavinger

Hey, this guy’s been in my safe!

Douglas Chachere
Guest
Douglas Chachere

Good article

GM
Guest
GM

With the popularity of 9mm uppers, mag-well pugs for S&W mags and deicated lowers for Glock mags I can’t beleive you did not even mention 9mm?

m
Guest
m

agree… I know it’s a little late to comment on this year+ old post… but 9mm is actually what I came to this article to find out about…

Allen Johnson
Guest
Allen Johnson

Haha. I still answer questions beat I can from this article all the time. I wouldn’t worry about how old it is. It’s a good article.

Brian Hall
Guest
Brian Hall

So did i, what a let down…. I have a new semi decked out .556 with a wylde ss spiral fluted barrel and the parts to complete my 300 blackout upper, just joined the local pistol club and I’might going from my sprinfield 1911 45acp to a springfield 1911 9mm and want a carbine in 9mm to use for different shoots, that’ll cover my bases. I have a springfield M14 M1A scout sniper 308 to round off any fun tactical shoots, Justin wanted to hear what everybody else has done. The 9mm will be cheaper to run and reload vs… Read more »

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m

You can use a normal lower but have to have a magazine block (several types out there). Or now there are quite a few dedicated colt or glock lowers being made. I just ended up with a palmetto state armory dedicated glock style. Some have last round hold open some don’t. Some times it’s on the upper… lots of info out there about 9mm ARs (sometimes called AR9)