NOT so accurate sniper rifles...........

[Bear44]

How effective is 5.56 at 400 yards, vs 7.62x54R at 400 yards, accuracy issues aside? Torso hit is a torso hit. Effective enough to puncture thru a windshield, body armor? When fired from M4? I have no experience with AR, so I do not know the answers.

That's the trade off of a lighter round. Any 7.62 round is going to handle barriers better than a 5.56 at any distance. But to give you some perspective, the typical 5.56 round has more energy than a typical 44 magnum, so it's not as lame as some seem to think.

With that said, it doesn't matter how well a round penetrates barriers if you can't hit it in the first place.

 

[Jeddak]

I think "combat" accuracy is the term I am looking for. If a semi-auto allows me to put shots in a 10" group at 400 yards and kill my target, I would rather have that than a 5.56 rifle that dents a tight group on top of a windshield. I just have to aim for a torso, and not a head. Is there anything wrong witn that thinking? Dead is dead.
44 magnum also punches bigger holes, and does not rely on fragmentation or yawing bullet to do the killing.

 

[cmshoot]

I think "combat" accuracy is the term I am looking for. If a semi-auto allows me to put shots in a 10" group at 400 yards and kill my target, I would rather have that than a 5.56 rifle that dents a tight group on top of a windshield. I just to aim for a torso, and not a head. Is there anything wrong witn that thinking? Dead is dead.
44 magnum also punches bigger holes, and does not rely on fragmentation or yawing bullet to do the killing.

Are we talking for a combat rifle, DMR, or Sniper?

A center torso hold is just fine, but you're assuming the other guy is just gonna stand out in the open and allow you to hold on his sternum. As a Sniper or DM, with a magnified optic, it's possible to find smaller, hidden targets, and ID someone as a threat......this may not be possible as a Rifleman with iron sights, or up to a 4x optic.

You may only have the head as a target, or the head an upper torso. Even military Snipers train to go center of mass when we have a full body to shoot at, but most threats ain't gonna give you that.

 

[Jeddak]

I was talking about using a 7.62x54R semi-auto rifle in a DMR role. And you are right, smart enemy might not present his whole body.
Bear's comment was that AR is more accurate than any Soviet semi-autos. My question is, if target is 400 meteres away, 5.56 will be less effective, so is it worth it to sacrifice some accuracy and step up to 7.62x54R instead? Especially if shooting at a target behind a light barrier?
Questions from a couch sniper .

 

[Bear44]

I think "combat" accuracy is the term I am looking for. If a semi-auto allows me to put shots in a 10" group at 400 yards and kill my target, I would rather have that than a 5.56 rifle that dents a tight group on top of a windshield. I just have to aim for a torso, and not a head. Is there anything wrong witn that thinking? Dead is dead.
44 magnum also punches bigger holes, and does not rely on fragmentation or yawing bullet to do the killing.

There's the problem. You underestimate the 5.56. It will do a lot more than dent a windshield at 400 yards. It's still travelling well past the speed of sound at that range. Also, this thread is not about what round is most effective in general combat. It's about what constitutes a "Sniper Rifle" and a 10 inch group at 400 yards ain't it.

 

[Bear44]

I was talking about using a 7.62x54R semi-auto rifle in a DMR role. And you are right, smart enemy might not present his whole body.
Bear's comment was that AR is more accurate than any Soviet semi-autos. My question is, if target is 400 meteres away, 5.56 will be less effective, so is it worth it to sacrifice some accuracy and step up to 7.62x54R instead? Especially if shooting at a target behind a light barrier?
Questions from a couch sniper .

Yes it is, because you can achieve that same effective group you like (10 inches) all the way out to around 600 yards with an average AR in 5.56 which will still be travelling at over 1100fps. That's a 50% increase in effective range. That's a lot of additional capability.

Now think about the weapons we use as dedicated sniper rifles and the comparison isn't even close.

 

[Jeddak]

Now think about the weapons we use as dedicated sniper rifles and the comparison isn't even close.

SV98 vs Remington Model 700? Bolt action vs bolt action? SVD vs M14? Semi-auto vs semi-auto?
Bear, you are a big fan of 5.56. And I see that. But to say that 5.56 will have no problem penetrating barriers and kiling someone at 600 yards seems to be a big stretch. Or even killing someone reliablywithout any body armor or windshield or any barrier... I thought 5.56 needs to travel at least 2500 fps to fragment? 1100 fps is 44% of that. It is slower than a 40 gr High Velocity 22LR at a muzzle, and I would never carry a 22LR for self protection.
At this we are talking about 7.62 size holes vs 5.56 holes. I still believe that there is no replacement for dispalacement, in whatever gun platform.

Thanks for being a good sport about the debate.

 

[cmshoot]

With the right ammo, I would take the more accurate 5.56, although I don't like that round in a Sniper role.

Why not go 7.62x51mm? Better distance, better accuracy and better penetration.

7.62x54R 7n1: 151grn bullet @ 2700fps for 2448 ft/lbs of energy

7.62x51mm M118LR: 175grn bullet @ 2580fps for 2586 ft/lbs of energy

Both those sets of data are using a 24" barrel for both cartridges.

With numbers like this I don't see the infatuation with the 7.62R. I think it's cool that it's been hanging around since 1891, I really do, but the 7.62x51mm/.308 is a better cartridge all-around.

 

[Bear44]

SV98 vs Remington Model 700? Bolt action vs bolt action? SVD vs M14? Semi-auto vs semi-auto?
Bear, you are a big fan of 5.56. And I see that. But to say that 5.56 will have no problem penetrating barriers and kiling someone at 600 yards seems to be a big stretch. Or even killing someone reliably. I thought 5.56 needs to travel at least 2500 fps to fragment? 1100 is 44% of that. It is slower than a 40 gr High Velocity 22LR at a muzzle, and I would never carry a 22LR for self protection.
At this we are talking about 7.62 size holes vs 5.56 holes. I still believe that there is no replacement for dispalacement, in whatever gun platform.

Thanks for being a good sport about the debate.

It's all about trade offs. Put a .223 caliber hole in someone at 600 yards and they are very likely to not want to play anymore even if it doesn't kill them immediately. If you are engaging a machine gun or mortar crew that is laying fire on your position, I'd rather shoot them at 600 yards than simply wish I was 200 yards closer.

Then, of course, the mic drop on this debate is called "M14".

 

[Bear44]

With the right ammo, I would take the more accurate 5.56, although I don't like that round in a Sniper role.

Why not go 7.62x51mm? Better distance, better accuracy and better penetration.

7.62x54R 7n1: 151grn bullet @ 2700fps for 2448 ft/lbs of energy

7.62x51mm M118LR: 175grn bullet @ 2580fps for 2586 ft/lbs of energy

Both those sets of data are using a 24" barrel for both cartridges.

With numbers like this I don't see the infatuation with the 7.62R. I think it's cool that it's been hanging around since 1891, I really do, but the 7.62x51mm/.308 is a better cartridge all-around.

Beat me to it on the 308/7.62x51.