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What's The Best Caliber For The AR-15?

Hey everybody, Clint here with Classic Firearms, out here today at Take Aim Training & Range. And we're here to bring you all our next video, all about AR calibers and what is the perfect caliber for you? And we've got an assortment of rifles and pistols laid out here in front of us. And let's just go ahead and hop right into it.

For those of you that don't know, the AR-15 is actually chambered in all sorts of different calibers. Granted, it was originally intended to shoot the 5.56 NATO cartridge or .223 Remington. But since then, let's just say that platform has expanded a lot. And today we're going to talk more about the common rifle calibers that are out there, staying away from larger bores, like .458 SOCOM or 550 Beowulf and all the other ones that are out there.

So we're keeping it relatively small, right? So the highest calibers we're going to be talking about are 7.62 or .30 cal. But the smallest one, of course, is going to be your standard 5.56 or .223. We've got some M855 loaded up in the Magpul mag here. And we've got it paired today with the Knights Armament SR-15, which I'm still building up. If you guys are new to the channel, you know that I'm eventually going to give this rifle away, once I'm done playing with it and drilling all over it. But we've got it paired right now with the Vortex Gen III 1-10 and I am really loving this optic so far. I've got a B5 Systems stock on it. But this is Knights' SR-15, it is a what I'm definitely going to consider a high-end AR.


Now we all know that the 5.56, .223 cartridge is adopted by the United States military, the 5.56 specifically. Again, green tip M855 is still what we are commonly issued. And it's a great cartridge. It shoots well and was originally adopted to replace the M14, 7.62 NATO, right? They figured, "Hey, if you can carry more of it, and it still has the same type of capacity that the .30 carbine cartridge does as far as it's a terminal effect on the target, then all right, cool. We'll take it." But what's great about it is it's light recoiling. It's a fast moving round coming in at right around 3000 feet per second, out of a 20 inch barrel. Out of a 16 inch barrel, like you see right here, it's probably dropping down to about 28, 2,900 feet per second. We'll take a couple of shots on steel and just see how it feels. All right.

So yeah, it shoots great. And the cartridge, again, that 5.56 NATO cartridge, guys, it's just fun to shoot. And it is a very effective cartridge. We do have videos out there about how effective is 5.56, .223, the two rounds compared to each other. But I think you guys know mostly about that caliber. So let's just go ahead and finish this magazine out and let's talk about a caliber we haven't heard much about.

Daniel Defense DD5V4 GEN II 18 M-LOK

6.5 Grendel

Oh man, that never gets old. All right. So next up, we've got something a little bit different. So you might be looking at this and be like, "Oh, we're going to talk about a 7.62×39 AR." Well, no, we're not. This is actually 6.5 Grendel. This is 7.62×39. They both fit, feed the same type of magazine. People tell you, you got to watch out when shooting 5.56 and . 300 Blackout, don't get your mags confused because that could lead to a bad day. Same thing with the 6.5, 7.62x39, very similar, but not quite, right? Now 6.5 Grendel came about in the early 2000s designed by the same guy that started Alexander Arms. And it's really supposed to be that middle ground between 7.62 NATO and 5.56 NATO.

So it's interesting looking because it's definitely a skinnier projectile backed by a lot of powder on that cartridge there. This is a 100 grain projectile versus the 62 grain that you see coming out of the 5.56, M855. And it's moving at anywhere between 27, 2,800 feet per second. So what we've got it paired up with today is the Fostech Lightning. This is a sweet rifle, alright? And it comes with a 20 round mag, but we got these Duramags that are 30 rounds. Figured we'd go ahead and take a couple of shots with it. So before we did the how effective is 65 Grendel with Matt, I actually wasn't too knowledgeable on this cartridge and this is actually my first time out shooting one. So let's see how this thing shoots, especially with this rifle.

Ooh. All right. So you can definitely tell that you're firing a little bit more powerful cartridge. That's for sure. The recoil on it, it isn't bad by any means, but it is substantially a little bit more. Well, that doesn't really make sense. Let's just say it's a quite a bit more than 5.56 and what I noticed there. Granted this is also only a six, seven pound rifle, so that might have something to do with it.

Man, first of all, this rifle feels great, from Fostech, looks fantastic. But that 6.5 Grendel round? Wow, that is super cool. Now something that's really cool is Serbia, where Zastava Arms is out of. Is actually looking at adopting the 6.5mm Grendel cartridge to be now their primary cartridge in their new M17 rifle by Zastava Arms. Go take a look at that rifle. It's a very interesting one, that's for sure. But it is looking like that might be their new primary firearm for their military, which is pretty cool. So 6.5 Grendel, like I said, it's supposed to be that cross between, or that middle ground of 7.62 NATO and 5.56. So it's supposed to have a lot better ballistics than the 5.56 downrange. And even, from what I've read online and done my research with, apparently it has better terminal ballistics. And actually has better penetrating capabilities at a thousand meters over the 7.62 NATO, which is pretty interesting if you asked me. So 6.5 Grendel is definitely a cartridge out there. If you're looking to reach out a little bit further, definitely check a look at the 6.5 Grendel.

FosTecH Lightning 6.5 Grendel


And then we've got one 7.62x39, because you want to scream America on the outside in your AR, but you're still, still just a Soviet bloc lover when it comes to the insides. Right? So here we are. This guy is also our current giveaway. This is the Maxim Defense PDX 7.62x39 pistol. And I am all about this guy. Let's shoot this song. But before we do, some people might be saying, "Why would you even want 7.62x39 in the AR? It wasn't designed to shoot 7.62x39." Well, the AR wasn't really designed to shoot a lot of different calibers that are available, but I can tell y'all that, it's actually a lot of fun.

If you want the, I guess you could say everything this cartridge can do out of the AR platform, then you get a 7.62x39 AR. Now, also too, there's, I don't want to say a misconception, but I think when people actually go out there and build their ARs chambered in 7.62x39, I've seen some reliability issues, feeding issues. And I think it might just be quality of parts, or also too, the quality of the work done by the end user. So whenever you're out there building it, make sure you are using good parts and make sure that you know what you're doing. All right? Let's take a couple of shots with this guy here. If you already saw our giveaway video, you've already seen it in action, but who doesn't want to see it a little bit more, right?

Oh man, that thing roars with that 5.5" barrel and the Hate Brake muzzle device. So 7.62x39 is the world's most popular caliber. Billions, if not trillions of rounds produced since the SKS came about, the AK-47, of course, but guys, it's a very popular round. It's a very effective cartridge, especially inside of 300 yards, thereabouts, and you can even reach it out a little bit further. And a lot of people like to think that the 7.62x39 just isn't an accurate cartridge. Well, I am here to debunk all that all day. It is a great cartridge. And just like you can get some base cheap .223, 5.56, that might not have a [boutelle 00:13:38] or anything else like that to it. You can actually get some very decent 7.62x39 ammo, and engage targets at 500 yards, and be pretty effective with it. So don't hate on 7.62x39. It's a great cartridge. And it's a lot of fun coming out of an AR platform, rifle or pistol, which is what this guy is here. Again, our current giveaway, which we'll talk more about that in a moment.

Radical Firearms FR-16

.300 Blackout

Last up is probably one of my favorites for when it comes to close quarters and that's .300 Blackout. .300 Blackout came to the market. Its sole purpose was to be shot close quarters and silenced or suppressed. All right. And you know, let's just go ahead and talk about this really quick. Let me know down in the comments if you'd like to have a video out there debating, discussing silencer versus suppressor and what that's all about. All right.

So first off we've got the NEMO. This guy right here, this is the Battle-Light Pistol. Notice this is a SBA3 pistol and I've got a Yankee Hill titanium .30 Cal can on it. And I do love to shoot suppressed. All right, let's go ahead and take a couple of shots with this guy really quick and just show you guys what all .300 Blackout is about. We are running, I think it's supersonic ammo, so it's not subsonic, but that's all right. Let's take a couple of shots with it.

My target dropped. Let's just take a couple of shots out here. Well now you can actually appreciate how quiet it is because compared to 5.56, 6.5, 7.62x39, all of that being shot unsuppressed, you can definitely hear the difference. Right?

That is way too much fun. So .300 Blackout, I think is the ideal cartridge. If you're... Texas, right, hog hunting, things along those lines, because you'd have that .30 cal cartridge that you can keep nice and quiet. And if they are nocturnal, and let's say, you're going low visibility, you have night optics, things like that, that you're running with. Then you need to be able to have a flash suppressor on your gun and keep that flash mitigation as mitigated as possible. Right. So yeah, running .300 Blackout, keeping it quiet, keeping it nice and flash suppressed is the way to go. And honestly, guys, it's just a lot of fun.

Nemo Arms Battle Light Pistol


You know what else is a lot of fun though, free guns, right? So I'm going to go back to our 7.62x39 here. This is the Maxim Defense PDX that is our current giveaway. I want to know from you guys, is it the 7.62x39, the 6.5 Grendel, the .300 Blackout, the 5.56 traditional AR, which one is best for you? And why? Let me know down in the comments sections. For me, it depends. It depends all day, every day, what I'm using the gun for. If I'm going to be out hunting or distance engaging targets, then you know what I think I might give the 6.5 Grendel, a couple more shots and try it out. It also has an adjustable brake on it, or excuse me, adjustable gas block. So I'd be interested to play with that some, see if I can get that tune just right as well. And see if I can actually mitigate the recoil a little bit more and maybe even try this guy suppressed as well.

But again, 5.56, that is just what the common cartridge is that the AR was originally chambered in and it's typically plentiful. But during this ammo getting age that we're living in it's, I know, it's crazy guys. By the way, if you are on our website, checking out what we do or may not have in stock, first off, thanks for visiting. And if you see something you like that we don't currently have in inventory, make sure you're signing up for our product alerts or notifications. The moment that that switch gets back turned onto in stock, you'll receive an email and you can go ahead and make your purchase. All right. But anyway, while you're at our website, don't forget to get your entries in for the Maxim Defense PDX chambered in 7.62x39. This guy is a lot of fun.

We're pairing it with the EOTECH 120 round mag. Already comes with the Radian Raptor ambi charging handle, the Hate Brake, and the SCW pistol brace on this guy. And it becomes a nice compact firearm. Look at that guy. That thing is sweet. And coming in at just under six pounds with the EOTECH mounted. And of course the ALG Defense Advanced Combat Trigger. This thing is just freaking cool. I love it. And I'm super happy that we at Classic Firearms are able to offer this guy to y'all as our next giveaway.

So again, head to our website, get those entries by hitting that top banner. It'll show you all the different ways to get your entries. And one of those ways is a code word gets you like 400 some odd entries. So don't miss out. Codeword is Maxim, M-A-X-I-M. Don't miss out guys. I'll see you all down in the comment section about your favorite AR calibers. God bless. And we'll see you soon.

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