7.62x51 VS AR as a Close Quarters weapon?

[Guest drv2fst]

There are MANY threads on here about various exotic calibers for AR's (6.5mm, 6.8mm, 300, .458, ...) that make the AR a better close quarters weapon. I wonder if it wouldn't be easier to use a rifle designed around 7.62x51 for this? Are there loads for 7.62x51 that are better suited for close quarters? How about a more rounded or even hollow point round? I imagine there is some projectile out there that would look more like a .45 (although a bit smaller in diameter). If it were heavy enough and maybe loaded down a bit on powder, I would think it would be suitable for close quarters.

I know many people have said you don't want to a file a normal .308 indoors if you can avoid it. But these rounds could be subsonic, easily suppressed, and fast burning enough to have a very low muzzle flash. They should be great for suppressors.

It would be a lot easier to change Mags from (long range ammo to up close ammo) than to change uppers.

There are several great 7.62x51 guns that appear to be well suited for Close Quarters (FN-SCAR 17, KelTec RFB, Springfield M1A SOCOM, PTR 91, DSA FAL Paratroopers, ...) but the ammo is not great for that purpose. Does anyone know of good Close Quarters rounds or loads for this caliber?

Just curious.

[Mike]

It would be easier to just put good quality ammo in the AR that works well inside people.

Several manufacturer's out there, Hornady TAP, Corbon DPX, etc.

[Caster]

Mike's right. We ain't bound by a convention man! Leave the FMJ and take to an Amax or Vmax, maybe a varmint grenade or even Midway's Dogtown softpoints. The .223 has more potential than the soldiers of the world are allowed to utilize.

[Guest drv2fst]

OK, maybe I wasn't as clear as I should have been in my original post. I'll try again.

Anyone know of any loads for the 7.62x51 that are better designed for up close and personal?

[Caster]

OK, maybe I wasn't as clear as I should have been in my original post. I'll try again.

Anyone know of any loads for the 7.62x51 that are better designed for up close and personal?

Purchased loads or handloads?

Either way, with something that large, I'd want a reduced load and a frangible bullet for houses and street to street.

[Mike]

I know many people have said you don't want to a file a normal .308 indoors if you can avoid it. But these rounds could be subsonic, easily suppressed, and fast burning enough to have a very low muzzle flash. They should be great for suppressors.

Subsonic .308 typically doesn't have enough energy to cycle the rifle.

Example.

[peejman]

There are several great 7.62x51 guns that appear to be well suited for Close Quarters (FN-SCAR 17, KelTec RFB, Springfield M1A SOCOM, PTR 91, DSA FAL Paratroopers, ...) but the ammo is not great for that purpose. Does anyone know of good Close Quarters rounds or loads for this caliber?

Just curious.

I don't think any of those rifles would be better than an AR SBR in close quarters. They're all quite long, even folded/shortened, etc. Special Ops forces use things like the MP5 and HK416 for a reason.

[Guest drv2fst]

The RFB is about 26". The SCAR folded is probably about the same. The PTR 91 pistol version is much shorter than that. It's no bigger than a MP5.

Plus, an MP5 can't reach out to 400+ yards effectively with just a magazine change. One of these 7.62's could convert from short range to long range as you change one mag of ammo for another.

It's all silly tactical armchair games anyway. I'm not SWAT and never will be. I just like the idea of getting great at operating a fewer number of guns that are better adaptable to many situations.

[Smith]

Personally, I really like the RFB for your purposes. The DRT ammo seems to be a good choice as well.

[Caster]

Another option would be a light for caliber, thin jacketed varmint bullet at very high velocity. That would help keep pressures up for good cycling in a short rifle, and keep penetration down which is going to be a problem with 308 in close quarters.

[Mike]

The RFB is about 26". The SCAR folded is probably about the same. The PTR 91 pistol version is much shorter than that. It's no bigger than a MP5.

Plus, an MP5 can't reach out to 400+ yards effectively with just a magazine change. One of these 7.62's could convert from short range to long range as you change one mag of ammo for another.

It's all silly tactical armchair games anyway. I'm not SWAT and never will be. I just like the idea of getting great at operating a fewer number of guns that are better adaptable to many situations.

An AR can. Even a SBR can go to 400 yards.

One of these 7.62's could convert from short range to long range as you change one mag of ammo for another

That's silly. ammunition doesn't need to be changed due to engagement distance. What's lethal at 400 yards is just as lethal at 10 yards.

Mike

Edited December 1, 2011 by Mike

[1gewehr]

That's silly. ammunition doesn't need to be changed due to engagement distance. What's lethal at 400 yards is just as lethal at 10 yards.

Mike

Actually, it's MORE lethal at 10 yards.

And what's wrong with 7.62x51mm ball ammo for close up? CQB combat sometimes (often) entails shooting through concealment (doors, walls, etc). The 5.56mm is notorious for poor performance against obstacles. It's why they came up with M855 in the first place. The Keltec RFB looks like it would be useful for CQB. I wish it were just a bit less expensive, and more available, though.

As an aside, when the Wolf 6.5Grendel steel case gets here, it looks like it would be useful for CQB. A 110gr, steel jacket with an excellent BC at 2650fps from a 18" barrel should give good penetration as well as good terminal performance. The more I shoot the 6.5 Grendel, the more convinced I am that it should be our standard rifle cartridge.

[Dolomite_supafly]

300 BLK in an AR would suite your needs. You can get factory ammo that cycles perfectly in subsonic as well as supersonic loadings. Uses standard AR magazines and is easily suppressed.

And honestly a suppressor does go a long way at reducing noise short distances with 5.56. It is when the bullet has enough time to make its supersonic crack that you get the loud suppressed noise. A suppressed 5.56 in a tytpical room isn't going to be tht loud.

If you are talking about a true building clearing gun I would use a pistol caliber. Mostly because those platforms tend to be shorter which makes room clearing easier than the full length battle rifles. If you do use a 5.56 with a short enough barrel to make clearing easy you are wasting a lot of the muzzle energy and in turn getting a lot of muzzle blast.

Dolomite

[Guest drv2fst]

That's silly. ammunition doesn't need to be changed due to engagement distance. What's lethal at 400 yards is just as lethal at 10 yards.

Mike

And is still very lethal when it goes through the BG and through the wall and through the neighbors window and into their children.

The "thought experiment" here is to find a round that I can load into my rifle and clear the house with if needed. But that same rifle (with different ammo) will serve well at the range or in a 3 gun match, or hunting.

[Dolomite_supafly]

Went back and read you post again.

If I was going to use it for QCB only I would use a lightweight and fast round. Perhaps one of the TAP rounds in 110 grain or even 155 grain weights. The 110 loading gets to roughly 10" in gelatin and the 155 flavor gets to 15". Both would probably reduce the chances of overpenetration during most engagements.

Now they are going to be loud and obnoxious when firing indoors. Even with hearing protection the concussion can be overshelming for some. Not to mention the muzzle blast if you are using shorter barreled guns. Now with a suppressor it is going to minimize most of the detractors and would be a viable option. But as I said previously you are talking a bout a full length battel rifle that isn't as well suited as other platforms to buildign clearing.

Dolomite

[Guest drv2fst]

300 BLK in an AR would suite your needs. You can get factory ammo that cycles perfectly in subsonic as well as supersonic loadings. Uses standard AR magazines and is easily suppressed.

And honestly a suppressor does go a long way at reducing noise short distances with 5.56. It is when the bullet has enough time to make its supersonic crack that you get the loud suppressed noise. A suppressed 5.56 in a tytpical room isn't going to be tht loud.

If you are talking about a true building clearing gun I would use a pistol caliber. Mostly because those platforms tend to be shorter which makes room clearing easier than the full length battle rifles. If you do use a 5.56 with a short enough barrel to make clearing easy you are wasting a lot of the muzzle energy and in turn getting a lot of muzzle blast.

Dolomite

With the AR scenario, we are talking AT LEAST having to change uppers to accommodate different calibers.

[TMF]

Plus, an MP5 can't reach out to 400+ yards effectively with just a magazine change. One of these 7.62's could convert from short range to long range as you change one mag of ammo for another.

It's not that easy to just "change out the ammo" to significantly change the ballistic properties, such as turning a .308/7.62 x 51 round into a low velocity pistol--type round and expect your (semi-automatic) weapon to function. It won't. Furthermore, if you're looking into a carbine for "CQB" I'm assuming you're wanting this for home defense and not domestic terrorism. If my assumption is correct you're going to want a pistol caliber carbine unless you live out in the country and aren't worried about throwing a few flyers through your wall. I have a few tactical rifles for the purpose of collection and sport but none of them are considered to be in the "home defense" category.

[Handsome Rob]

As an oddly lateral though, how about producing an AR in 7.62x39? I don't know if anyone makes one already, I know less about ARs than I do about Quantum Physics, but it seems like a logical choice to me. A bit more 'hoof' than the 5.56, a bit more friendly than the x51 or x54. More round-weight for long range momentum & higher KE, enough to shoot through obstruction (I guess) & good for the CQB stuff. It has the added advantage of being readily available, cheap & there should be lot's of dead Chi-Comghaniraqui bad guys lying around carrying your reloads.

I've had a drink though, so I could be talking out of my bum.

[mikegideon]

As an oddly lateral though, how about producing an AR in 7.62x39? I don't know if anyone makes one already, I know less about ARs than I do about Quantum Physics, but it seems like a logical choice to me. A bit more 'hoof' than the 5.56, a bit more friendly than the x51 or x54. More round-weight for long range momentum & higher KE, enough to shoot through obstruction (I guess) & good for the CQB stuff. It has the added advantage of being readily available, cheap & there should be lot's of dead Chi-Comghaniraqui bad guys lying around carrying your reloads.

I've had a drink though, so I could be talking out of my bum.

A 300 Blackout pretty much IS a 7.62 x 39.

[Dolomite_supafly]

A 300 Blackout pretty much IS a 7.62 x 39.

+1

Without all the reliability issues of trying to feed the 7.62x39.

Dolomite

[Handsome Rob]

Ah ha. Did not know that.

Which begs the question; So why re-invent the wheel with the 300 BLK when the 7.62x39 is so close?

What are the feed issues associated with the x39? AKs seem to do OK?

Edited December 2, 2011 by robtattoo

[peejman]

Ah ha. Did not know that.

Which begs the question; So why re-invent the wheel with the 300 BLK when the 7.62x39 is so close?

What are the feed issues associated with the x39? AKs seem to do OK?

It's simply that a big manufacturer with good engineering resources hasn't ever bothered to solve that problem. There isn't enough demand to support that (though I'd love to have an AR in 7.62x39). I don't know the details, but believe its something to do with how the mag sits in the lower and how the bolt strips rounds off. There are 7.62x39 AR's that run, but they've been tweaked by patient owners.

Also the 7.62x39 cartridge has a (mostly undeserved) reputation for not being especially accurate. The AR platform is supposed to be "minute of man" out to 500 meters.

[Caster]

It's simply that a big manufacturer with good engineering resources hasn't ever bothered to solve that problem. There isn't enough demand to support that (though I'd love to have an AR in 7.62x39). I don't know the details, but believe its something to do with how the mag sits in the lower and how the bolt strips rounds off. There are 7.62x39 AR's that run, but they've been tweaked by patient owners.

The problem is that the cartridge [7,62x39] has a very pronounced taper. To feed it reliably, the magazine must have an accommodating radius. That's where the old term of banana clip came from. AK mags are heavily curved. Because an AR magazine isn't, and by design, the AR mag well goes straight in, you have the problem. 7,62x39 doesn't like to feed stacked straight like .223/5,56 The remedy has been godawful looking magazines or worse, and lobbed off lower that accepts AK magazines, although the AR lower that takes AK magazines has [from what little I know] an excellent track record for feeding. Doesn't matter, it still looks ridiculously crappy.

The .300whisper/fireball/blackout solves this by building [basically] the same cartridge with very little taper thereby feeding in straighter magazines of the AR.

There's always some goober trying to ice skate uphill. If you want .223 in a relentlessly reliable package, buy a quality AR. If you want 7,62x39, buy an AK. Simple.

But what do I know?

[Mike]

Also the 7.62x39 cartridge has a (mostly undeserved) reputation for not being especially accurate. The AR platform is supposed to be "minute of man" out to 500 meters.

As you said its mostly undeserved. Folks that propagate this usually are the ones buying the cheapest rifle that they can find, shooting the cheapest milsurp ammo they can buy and complaining that it won't group.

Mike

[mikegideon]

+1

Without all the reliability issues of trying to feed the 7.62x39.

Dolomite

I like the Blackout. May never get around to playing with it, but I sure like it.