Best cartridge for a “Long Barreled Pistol” possible SBR

R

Rich_357

New member
I’m putting this in the Handgun forum because it would most likely start off as a handgun and eventually go SBR.

I apologize if this has already been covered but I’m curious as to what would you consider the best cartridge for a SBR or “Long Barreled Pistol” (pistol and rifle rounds inclusive.) I’ve been doing a lot of reading and there are pros and cons between 9mm, .223, .556, 300 BLK, 7.62X39 ect.

Things to take into account.

1) Said rifle/pistol wouldn’t be used in excess of 100 yard. 25-50 yard would probably be the maximum for most plinking. With that said, it needs to be very effective at under 25 yards.

2) Flash bang. Being used in a Home defense situation, I’d prefer not to go deaf and blind all in one pull of the trigger. Suppressors yes but that is additional.

3) Ballistics from a barrel between 8” and 12”. I’d like to keep the barrel under 12” as it makes the rifle/pistol more maneuverable in close quarters.

4) Wall penetration. Just because a round hits hard doesn’t mean that you want it to penetrate several walls.

5) Weight. Even short barrels can be cumbersome when you cram all of the guts into a small package.

6) Ammo affordability.
 
I'll say 5.56 in a 10.3"-11.5" barrel. It ticks most of the boxes you're looking at. Sound will be loud out of something that short however.
 
Based on my own thought experiment about building something like what you're talking about, my initial thoughts are:

9mm
.300 Blackout
5.56
7.62X39

In that order. That's assuming you want to stay with an AR type gun. 7.62X39 would jump up the list if you wanted to do an AK, for instance.

Everything is going to over penetrate walls and the light grain bullets which fragment when going through walls are probably not the ones you're going to be running out of a 10 inch barrel. Most people running those will choose something like a 75 gr SMK for its better ballistic performance out of short barrels.
 
The requirement for a SBR with a barrel length of 12" or less may be difficult. Handguns, no problem but a rifle could be a problem staying legal. I understand 16" is the shortest legal barrel length for a rifle. A number of manufacturers make 16" barrel rifles. Taking all this into consideration I suggest .357 Magnum. As you know .38 Special can be used in all .357 chambered firearms and this enables one to use a wide variety of ammo in both of these calibers. The ammo is reasonably priced and is one of the most popular calibers for reloading. By reloading both calibers can be tailored for about any purpose or use. There is a large number of both rifles and handguns available for .357, .44 Magnum and .45 Colt as well. .44 Magnum can also use .44 Special.

I have a number of .38 and .357 revolvers and not long ago purchased a .357 lever action rifle. I wanted a 16" barrel but could not locate one so I settled for a 20" barrel. I am a long time (35+ years) reloader and load .357 for the rifle a little different than for a handgun, specifically use Alliant 2400. Depending on hand gun's barrel length I use either Unique, AA 5 or AA 7.
 
I have a PAP M92 but IMHO it's too heavy for close quarters combat. Don't get me wrong; its a beautiful gun and you'd have to run over me twice for me to give the sucker up.

I tend to agree on the 9mm and 556. I really don't know much about the 300BLK other than it has similar ballistics to the X39; it seems a little much in close quarters. I'm seriously leaning towards an AR pistol in 9mm.
 
Thanks Saber9; I've got a 357 and she my baby doll. If I went to a pistol round, I'd like to stick to 9mm due to the price and because it's what I normally shoot at the range. What I am looking here is an intermediate to short range "pistol/rifle" that could be possible turned into a SBR (Short Barreled Rifle). That transition requires a lot of paperwork and $200 to make it legal. Gotta love the feds. :rolleyes:

Edited because I tend to skim read. ;)
 
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100 yds

The 100 yd self imposed limit on your firearm makes me think that you will be well served with a pistol cartridge. Your desire to limit flash/bang without requiring a suppressor supports that.... almost any high intensity rifle round in a short barrel will have excessive report and blast.

My immediate thought was a Glock, either the new Glock 40, or a G20 with an aftermarket longer barrel. One could then make the jump to one of the Mech/Tech carbine conversions pretty easily. Regards caliber, I thought 10mm, but there may be issues with ammo availability......you can't easily run out and acquire bulk 10mm at a chain store. Also, 10mm is a high pressure round and may be more flash/blast than you want indoors.

If you could live with a looping trajectory to 100, the .45 acp seems the next best choice to me. A low pressure round, available in bulk, with a wide variety of projectile types. I am not sure you can acquire a "long" Glock pistol barrel, but the MecTech G20 is relatively proven as a carbine.

I realize we are on the semiauto forum, but one of the Mares Leg lever-pistols, equipped with a full size stock (neccessitating an SBR stamp) seems an interesting arrangement to me. In something like .44mag or .357, you could load it up or down to suit (mag or special) and a wide range of bullet weights to boot. I have no use for the things as sold, it's not really a pistol, and its not a carbine either, but one w/ a real buttstock seems appealing.
 
Thanks dakota. Seriously though, after going through all of the research and the posts....I think that I'm going with a AR9. We shall see...

Edit: The prices for AR-9 vs AR-15 are ridiculous and they are out of stock on most 9mm options. I will not buy a gun tonight......I WILL NOT buy a gun tonight. Maybe tomorrow :D
 
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Well after browsing around for a while, I’ve reconsidered. In this situation, you can legally go from pistol to rifle but not the other way around.

I think that I’m just going to look into a AR multi-caliber pistol lower with a 10.5” upper. I’ll probably eventually pick up a 16” upper and buttstock; the best of both worlds. :cool:

http://blog.adamsarms.net/blog/ar-pistol-vs-sbr said:
The main difference between a short barreled rifle and an AR pistol comes down to two things. First, an AR pistol does not have a buttstock and is not intended to be fired from the shoulder like an SBR. Second, to build an AR pistol you must not use a rifle receiver that has been barreled and/or stocked as a rifle action, the first build of a lower will determine what the lower is from that day forward. If the lower was first assembled into a rifle then it is considered a rifle forever. Keep in mind that in general, you can attach a buttstock to a pistol if you change the barrel to greater than 16" as well. If you do not change the barrel and it is less than 16" in length this would than be considered a short barreled rifle. Also, if you are in possession of a rifle buttstock that could be installed on your pistol, this can constitute possession of a short barreled rifle.
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Rich... you may have made up your mind already, but let me through this in the mix. I just picked up a CMMG MK9 from Buds for $783. I got a chance to shoot it today, and it was a great time. I shot 400 rounds through my pistol. It runs perfectly. If you have done your research, you know that the Colt pattern AR9 is the way to go. Most Glock type lowers do not have a last shot hold open. The Colt types do. The MK9 is a Colt type, and my gun functioned just like any AR should.

I also have a 5.56 AR pistol, and shooting it is an experience. I built it with the idea that it might be used for home defense. That went out the window the first time I shot it without hearing protection, just to see how bad it really was. I took a couple shots today with the 9mm without hearing protection, and it wasn't bad at all.

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A 9" unsuppressed .300 BLK with the AAC flashhider has zero flash, even at dusk. It will throw a 110gr VMAX at 2200fps, which gives you a limited penetration round that will outperform most pistol calibers (http://m.hornady.com/store/300-Whisper-110gr-vmax/). You can also switch to a 110gr TSX for a barrier blind round with the same point of impact. Bang-wise, it is a rifle and it will be loud but much more tolerable than a 9" 5.56 or 6.8, and certainly nothing someone who shoots a .357 pistol can't handle.

Premium supersonic ammo is in the $1/rd range. Blasting ammo can get very cheap if you reload. You won't get 9mm cheap without reloading your own cast lead subsonics, which are going to have a dramatically different zero.

Otherwise, your criteria basically describe the very weird niche .300 fills perfectly. The only box you missed checking is the "I want to go from quiet surpressed subsonics to a genuine rifle caliber with just a switch of a magazine."
 
Pretty much any comment in this thread that hasn't said .300 Blackout shows either a profound lack of research and/or a lack of personal involvement in the SBR.

A 5.56x45mm NATO round fired at anything under a 14.5 inch barrel, and even then, discharges unspent powder that turns into a fireball and concussive wave. A 10.5 inch SBR/CQBR needs a suppressor to eat up the flash and blast, or it is downright impolite to shoot, even on an open range.

The .300 Blackout, however, can burn the vast majority of powder within approximately 9" of barrel length. This leaves you with a wide range of loads that are effective out to, and beyond, 100m. You can take .300 BO supersonics out to 300m with ease.

The idea that a 9mm in a buffer tube mounted AR platform would somehow be preferable to a piston driven system (CZ Scorpion) or even just a braced Glock, is nonsensical. IF you want a 9x19mm platform, and with it all of the ballistic limitations of the 9mm cartridge, the Scorpion or braced Glock gives you 90% of the functionality of the 9mm AR with half the cost in a smaller package.

A 5.56x45mm 11" barrel can and will do the job. My next SBR project will be using an 11.5" reduced gas port barrel, but I am building this specifically as a suppressor host, and justifying it due to the immense availability of the 5.56x45mm / .223 cartridge. The advantages of a 5.56x45mm round over a 9x19mm are so great that to expand to the footprint of an AR platform and NOT upgrade cartridge seems absurd. That same lower, however, will be hosting a 9" .300 BO upper.

If you are going to stay married to the AR platform, consider an 11.5" reduced gas port upper, OR just go straight for the .300 BO. Keep your 14.5"+ uppers in the 5.56 cartridge.
 
Thanks guys.

I had decided on an AR9 build but after looking around, I chose a different path. I’m the SKS/AK guy; don’t ask me how many I own. :P I think this is a good chance for me to step into the AR realm. I am going to be frank, the AR9 prices were too high and the deal on the AR15 parts were too good to pass up.

The lower is multi caliber including 9mm; there are options if I decide to change things up. The upper is a very nice 10.5” that was a steal; I'm not going to lose any money if I decide to sell it. I know that you lose a lot of velocity with this length but a nice HP or SP round can make up for that at lower speeds. You guys have pretty much convinced me that this is not a HD weapon; I’m good with that for now.

I do agree that 300BLK and x39 are superior in a SBR and that a 9mm SBR is superior for HD situations. For now, this is what I picked.

I may actually pick up a High Point 9mm Carbine for a truck gun when the piggy bank is happy again. The thing is no beauty queen but for $250 and a lifetime warranty… :cool:
 
A 10.5" 5.56 will work fine for home defense; but it will be loud and more care must be given to ammo selection since less velocity means you don't always see the explosive fragmentation that reduces 5.56 penetration indoors. My personal view is if I am shooting at someone in my own home I want it to be "wake the neighbors" loud and give the bad guy the impression that Zeus is hurling lightning bolts at him - so flash and blast are not always a bad thing.

And unless you are just really sensitive to flash/blast, I can't think of too many areas where a 9mm carbine is going to be more effective than an AK or AR15 in an intermediate rifle caliber.
 
I'm not sure if this will work, but I've seen nothing to make me think it wouldn't work, but Nutnfancy did a video at SHOT last year about a Glock accessory called the Micro Roni:

0000840_micro-roni.jpeg


It's basically a really nifty shoulder stock that a Glock pistol fits into and it has a pic rail on the top to put folding sights or an optic. It also has a spare mag holder built into the vertical foregrip.

I'm thinking you could probably buy a Lone Wolf 9 inch extended barrel and slide the Glock into this Micro Roni and you'd have your SBR AND a standard Glock pistol as none of this is a permanent solution.

Now that I thought of this, I might look into doing this myself :D. It won't be cheap, the Lone Wolf barrel and Mirco RONI will cost a combined $400 and then there's the $200 tax stamp.

EDIT: and if it's not obvious, I think you should consider this being a pistol cartridge, even if you don't go for my idea. A suppressed pistol SBR is very quiet and much better than a suppressed rifle SBR, imo, as you don't have to worry about the supersonic crack.
 
Rich_357 said:
Well after browsing around for a while, I’ve reconsidered. In this situation, you can legally go from pistol to rifle but not the other way around.

I think that I’m just going to look into a AR multi-caliber pistol lower with a 10.5” upper.
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Just to clarify in case there's a misconception, it doesn't make any legal difference if the lower is marked "pistol" or "multi".

As far as the ATF is concerned, there is no such thing as a "pistol lower", and the caliber markings on the lower (or lack thereof) have no legal bearing on what calibers you can build the firearm into.

If you make it into an SBR, part of the engraving requirements are that the caliber be marked on the barrel or frame or receiver of the weapon, but since virtually all AR barrels have the caliber already marked on them, that's already taken care of and doesn't need to be engraved anywhere else.
 
Actually, it all depends on how the lower is registered and the first build. From what I have read, please correct me if I am wrong.

Technically, if the lower receiver does not have a stock it can be registered as a handgun. However, the first build must also be in handgun configuration and you must not be in possession of fitting buttstock unless you own a 16”+ barrel. Once, you purchase a 16” barrel, it is perfectly legal to add the buttstock as long as you change the upper to 16”+. Adding the buttstock without adding 16”+ upper reclassifies it as a class II firearm. Being in possession of a buttstock without owning a 16”+ barrel also reclassifies it.

With that said, it is illegal to turn a firearm that was originally registered as a rifle or originally built in rifle configuration into a handgun without a class 2 SBR license.
 
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Rich_357 said:
Actually, it all depends on how the lower is registered and the first build. From what I have read, please correct me if I am wrong.
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That's not entirely correct. First, there is no firearm registration as far as the feds are concerned. Second, you can't buy a new receiver as a handgun or a rifle (or anything else for that matter); it's simply a "receiver". A dealer doesn't get to put whatever he wants on the 4473 as far as the firearm type, and he can't base it on the buyer's future plans for the firearm build. No, the dealer has to sell the firearm as it actually is. A new receiver is simply a receiver. It can't be sold as a pistol or a rifle, even if the receiver has a stock on it. So if you're buying the receiver and the dealer puts anything other than "receiver" on the 4473, he's wrong and he somehow missed the open ATF letter from 2009:

https://www.atf.gov/file/60686/download

But you're correct that if you first build a receiver into a pistol it can go back and forth between being a pistol or a rifle, and if you build it first as a rifle it can't go back to being a pistol. This was determined by the Supreme Court in US v. Thompson-Center Arms Co. and further clarified by ATF ruling 2011-4.

Rich_357 said:
Technically, if the lower receiver does not have a stock it can be registered as a handgun.
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This is also not correct. Not only can you not purchase a receiver as a handgun, but it doesn't make a difference if the receiver has a stock on it or not: A new receiver is always simply a receiver. If it comes with a stock on it that doesn't change anything. You could still build it as a pistol if you wanted to. The ATF is very clear on this:

http://www.typicalshooter.com/atf-putting-a-stock-on-an-ar-15-lower-does-not-make-it-a-rifle/

And that makes sense considering the definition of a rifle involves a barrel. How can a firearm be sold as a rifle if it doesn't have a barrel? The answer is that it can't.

Rich_357 said:
Being in possession of a buttstock without owning a 16”+ barrel also reclassifies it.
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Not necessarily. See ATF Ruling 2011-4. In short, to be in violation of constructive possession of an SBR simply for having the parts to make one, those parts must be in "close proximity" to each other and you must also have "no useful purpose" for having them. The "useful purpose" part makes sense; basically, you need to have a legal use for those parts to explain you having them. (For example: If you have a few short-barreled uppers lying around with a few rifle-configured lowers, you have a "useful purpose" for having those short uppers if you have a pistol-configured lower nearby that they could fit on. Or if you had an AR pistol and a stock lying around, you have a "useful purpose" for that stock if you have a regular 16" rifle it can go on.) But I once asked an ATF agent what "close proximity" means and he told me to ask a lawyer.
 
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Thank for clearing that up!!! :cool: Stupid question that, as you stated, probably needs to be posed to a lawyer.

Legally, HOW in the hell do you prove what the first build configuration of a given reciever is? LOL Personally, I'm just going to take a dated picture and store it away. There ya' go.
 
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