Bought a 10.5" 7.62x39 for the house, but after recent events, am considering sometimes carrying in the vehicle.  7.5" would be easier for movement in the vehicle, but wondering about speed for both.  Someone is interested in the 10.5", so considering buying a 7.5".



Thoughts?

If you are going 7.5" in a 30 caliber rifle, I would highly suggest 300 BLK. Get it in subsonic and suppressed and it can't be beat.

Hi,

You can expect 1950-2000 fps out of a 7.62x39 cartridge from a 7.5" barrel with a 124 grain bullet.  PWS is now offering a 7.5" upper again too.

PWS MK 107 7.62X39 LINK

For your philosophy of use I.e. car gun, practice, lots of rounds shot I think the 7.62x39 with its lower cost will serve you better.

Good Shooting:

That upper is the shit. If you look around, you can usually buy it cheaper. Or, you could build one yourself on the very cheap. Nothing out there in a short barrel as cost effective as the x39 round. The 300bo is a great round but the cost is prohibitive for me.

Not only is it cost prohibitive from an ammo standpoint, but it's primary application is that of  Suppressed Short-Barreled Rifle/Pistol which adds NFA costs on top of a suppressor which can be quite pricey.  Honestly the x39 just makes more sense to me from a cost and ballistics standpoint.  You can also go with some 154-gr rounds and really pound some shit.

What are you talking about? He is asking about a 7.5 inch to 10.5 inch barrel which is an NFA item with either the 300BLK or AK.

You did nail part of it as the 300BLK blows the doors off the AK when it comes to SBRs as the 300BLK is made to burn most of its gas in the first 8 inches of the barrel meaning it will give you less loss of FPS when using a shorter barrel, it will also mean less of a fireball when using a shorter barrel and in turn will mean it makes a lot less noise when using a shorter barrel. It most certainly doesn't need a suppressor to make it work but adding one just makes it that much more capable especially when shooting subsonics.

The only thing the AK has going for it is cheap ammo which is exactly what you pay for. You get ammo that is less than accurate and usually not reloadable. If you plan on shooting thousands of rounds in the desert cracking rocks or kicking up dirt then the AK with its cheap plinking ammo would make sense but if you don't shoot thousands of rounds then it make far less sense. Since you cannot use standard AR equipment for the magazine, bolt, lower or barrel.

This becomes very problematic when you want to SBR your lower. Because if you SBR a lower specifically made for the AK like the Rock River then that is the only upper you will be able to put on it. Now if you SBR a standard AR lower letting you put anything from .223, 9mm, 6.8, 6.5, 458 SOCOM or the 300BLK you will have to use special AK mags forced to fit into the standard AR mag well which end up being a poor substitute for the standard AK mag and have been much less reliable than what a standard AK mag will give you. There is also the bolt issue that trying to stuff a 7.62X39 round into a modified AR bolt takes a ton of metal off and makes it a weak point so if you do plan on plinking a lot of ammo out of it plan on replacing the bolt.

With the 300BLK you get all the advantages of the AK without having to deal with the limited capabilities of the 7.62X39 ammo. You get the ability to penetrate barriers, windshields, car doors, brick or wood over the 5.56.

With the 300BLK there is a lot more range of bullets available to it as anything that can be shot out of the .308 can be used in the 300BLK. This gives the shooter a lot more options when hunting to use 110gr vmax for varmints or coyotes, 110gr Barnes Black tips for personal protection and animals around 250 pounds or a variety of 125gr bullets that will start to take on anything from 50 pounds to 300 pounds plus. While the AK may have some of these bullets available they usually cost more than the 300BLK ammo and you will have less to chose from.

Simply put if you are going to SBR a rifle the 300BLK that only needs a change of the barrel to work while using all other standard AR parts make a lot more sense than trying to cram a round that was never even conceived for the AR into an AR.

BTW subsonic is a nice bonus that the AK doesn't do.

The PWS upper is an amazing little piece of kit, mine runs without issue :)

Easy killer.  My point was simply that the .300 was meant to run suppressed and if you want a stock rather than a pistol tube at the barrel lengths he described, then it's a "pay to play" proposition.  You throw in the two stamps(SBR and suppressor), plus the cost of a can and it really adds up in a hurry.  Not to mention the cost of .300 ammo is significantly higher than x39.  Sure you can reload, but the initial cost of that isn't cheap either (good tools aren't cheap/cheap tools aren't good).  As for the x39 in the AR platform and durability, I've had zero issues with my build and I'm building an x39 pistol while waiting on the lower to clear NFA jail so I can slap a stock on it.  There's also plenty of other people on the forums here that have great experience with the x39 on this platform, so saying that the only option is to build on the AK platform is simply incorrect.  You don't have to run frankenmags for reliability, CPD and ASCs work fine.  A quality bolt from Cason Engineering or LMT have proven very durable and reliable.  

Personally I don't feel the x39 gives up that much to the .300 to warrant the additional ammo cost.  Just my opinion.

Why do you keep saying it needs a suppressor? The 300BLK works perfectly fine without one and is only made that much better when added but by no means does it need to have a suppressor.

You have to see the humor when you say the 300BLK was meant to run suppressed yet you do understand that the 7.62X39 was meant to run in an AK.

The ammo cost is the only advantage that the AK has over the 300BLK and the fact that the plinking ammo for the 300BLK is far superior to what you get by buying the russian ammo.

This all goes back to if the OP wants an SBR the 300BLK is a far superior choice especially when it comes to shorter barrels and the cost difference in ammo is minimal unless you are firing hundreds of rounds a week. Especially if you are running anything other than cheap russian stuff the 300BLK almost always is cheaper when it comes to hunting, self defense or any other type of ammo other than cheap plinking ammo.

All I will really add is that my Draco (12" 7.62x39) is really freaking loud and throws a huge fireball. No way would I want to shoot a 7.5" 7.62x39 out of a car.

So, I'm guessing somehow the RPD and SKS (which prefaced the AK) managed to use round that as you say, "was designed for the AK" even though  that rifle wasn't designed yet. Your blind ignorance is down right potato.

True. But the AK was designed to use the 7.62x39 round while the AR was not. The AR has had some issues running the 7.62x39 round (due to magazine design primarily), though I understand they have mostly been worked out. The 300BO has generally been easier to run well in the AR platform. The ammo price difference does make the 7.62x39 appealing.

So, I'm guessing you completely missing the point that everyone else got is down right rhubarb.

The whole 7.62x39 vs. 300BLK is simply rutabaga.



7.62 is a long barrel round, 300BLK is a short barrel round.

I never saw the sense in pistol round rifles either.

Use the right tool for the job.



 

7.62 is a long barrel round, 300BLK is a short barrel round.
I never saw the sense in pistol round rifles either.
Use the right tool for the job.

Thats how I see it, if you are going to go with anything under 10.5 I would choose the blackout, unless ammo cost is a huge consideration.  IN a 16 inch or longer barrel the x39 really gets going and can do everything supersonic the 300 blk can and more, to go along with finding cheap plinking ammo.

as a rabid 300 blk fan, my truck gun is an 12.5 inch barreled AK pistol.  it was cheap to build and if the truck gets stolen I am out about $500.  $250 for the gun, another $100 for the mags and ammo and $150 for the beat up 95 f150 truck


I may at some point in the future build another 300blk pistol and that would end up as my truck gun.  but for now my short barreled 300blk resides on my SBR lower.


and for all the "300blk was designed for short barrel crowd"  you may need to do some more research.  the 300 blk was designed to be used in 16 inch barrels and shorty barrels.  and don't give me another lecture on the origins, I was into the 300blk before there was a 300blk.  I was shooting deer subsonic before it was cool.

x39 is def louder out of micro guns, perhaps too loud uf ur not runnin a can.

plus, it can be tricky to get an ar to be 100% reliable in 762x39.  recommending the ak w x39 if u want cheap gun to train and maybe fight for your life.