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The Ballistic Facts Of Life - John Farnam

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The Pentagon’s unwavering loyalty to the 5.56x45 cartridge may be faltering, at long last, but we are once again confronted by the Laws of the Universe.

New materials, new coatings and other surface treatments, new machining methods and technology, new propellants, all help, but “game-changing miracles,” though much falsely claimed, are pretty much confined to the Old Testament!

Once again:

Autoloading military rifles, chambered for 5.56x45, are suitable, maybe even ideal, for domestic personal defense and as police patrol rifles.

But, as a “main-battle-rifle,” the caliber is inadequate, in both range and penetration. And, all the “wonder bullets,” proposed and issued, since the 1960s have fallen far short of adequately addressing these two critical issues.

And, short barrels make a bad problem even worse!

So, here is the unhappy truth:

While DOD wants a more powerful cartridge, effective to 500m, they don’t seem to consider that it is invariably going to require a rifle that weighs more and has a longer barrel than the current M4.

Barrel length, overall rifle weight, propellant capacity, bore diameter, durability, effectiveness:

All these parameters have to be balanced against unavoidable trade-offs, inherent with each.

A large ratio of propellant to bore-diameter (1) requires a long barrel length and (2) shortens barrel life.

A large bore diameter and (of course) a heavier bullet requires a heavy barrel and large cartridge cases, which means increased recoil and decreased magazine capacity. Big case-heads require big bolts.

It seems we have be trying to find the best compromise since the Mauser Brothers first introduced bolt-guns and smokeless propellent, back in the 1800s!

In fact, the original 7mm Mauser was a pretty good military cartridge. Still is!

Then, there was the 280 British, 276 Pedersen. Probably adequate, but never adopted. The 6.5x55 Swedish is in the same category.

A military cartridge needs (1) generous case-taper for easy feeding and extraction, (2) limited pressure for reliability, durability, long barrel-life, and slow heat build-up, (3) a ballistically-efficient bullet, heavy and tough enough for adequate penetration, and (4) sufficient muzzle velocity to keep the bullet supersonic out to at least 800m.

The new generation of cartridges, including the 224 Valkyrie, 6.5 Creedmore, 260 Remington, et al make good, long-range sniper calibers. But, with a light, skinny bullet, combined with a barrel with a fast twist-rate, we inherit rapid heat build-up, short barrel life, and the requirement for a long barrel. Significant muzzle velocity is sacrificed for every centimeter of barrel-length reduction. Thus, any of these calibers, in a short-barreled rifle (carbine), represents a contradiction of terms!

The first thing DOD is going to have to acknowledge is this:

When they really insist on a 500m rifle with acceptable penetration, that rifle will need at least a twenty-inch barrel and will have to be chambered for a cartridge with a bullet as least twice as heavy as that of the current 5.56x45.

Unhappily, what DOD has fanatically avoided confronting for the past forty years is the fact that they are going to have to, at long last, actually train real riflemen to kill individual enemy soldiers, one at a time, with accurate, semi-automatic rifle-fire.

I’m not at all sure they even know how anymore!

DOD could have an adequate main-battle-rifle, as described above, complete with appropriate optics, rails, etc, in the hands of front-line Soldiers and Marines in less than a year, all for a fraction of the cost of a single stealth fighter, if there were any will at the highest levels to actually get it done and finally put this issue behind us.

I’m less optimistic than I was a year ago!

/John
 
Don’t we hear that in most cases the firefight is within 75m or thereabouts? I get having a couple DMRs in the squad should it extend out, so are they being targeted from longer ranges now or what? I’m not on the battlefield so I have absolutely no say or conclusions drawn.

That said, if the military scales back on the 5.56, I will welcome cheap surplus with open arms.
 
The Pentagon’s unwavering loyalty to the 5.56x45 cartridge may be faltering, at long last, but we are once again confronted by the Laws of the Universe.

New materials, new coatings and other surface treatments, new machining methods and technology, new propellants, all help, but “game-changing miracles,” though much falsely claimed, are pretty much confined to the Old Testament!

Once again:

Autoloading military rifles, chambered for 5.56x45, are suitable, maybe even ideal, for domestic personal defense and as police patrol rifles.

But, as a “main-battle-rifle,” the caliber is inadequate, in both range and penetration. And, all the “wonder bullets,” proposed and issued, since the 1960s have fallen far short of adequately addressing these two critical issues.

And, short barrels make a bad problem even worse!

So, here is the unhappy truth:

While DOD wants a more powerful cartridge, effective to 500m, they don’t seem to consider that it is invariably going to require a rifle that weighs more and has a longer barrel than the current M4.

Barrel length, overall rifle weight, propellant capacity, bore diameter, durability, effectiveness:

All these parameters have to be balanced against unavoidable trade-offs, inherent with each.

A large ratio of propellant to bore-diameter (1) requires a long barrel length and (2) shortens barrel life.

A large bore diameter and (of course) a heavier bullet requires a heavy barrel and large cartridge cases, which means increased recoil and decreased magazine capacity. Big case-heads require big bolts.

It seems we have be trying to find the best compromise since the Mauser Brothers first introduced bolt-guns and smokeless propellent, back in the 1800s!

In fact, the original 7mm Mauser was a pretty good military cartridge. Still is!

Then, there was the 280 British, 276 Pedersen. Probably adequate, but never adopted. The 6.5x55 Swedish is in the same category.

A military cartridge needs (1) generous case-taper for easy feeding and extraction, (2) limited pressure for reliability, durability, long barrel-life, and slow heat build-up, (3) a ballistically-efficient bullet, heavy and tough enough for adequate penetration, and (4) sufficient muzzle velocity to keep the bullet supersonic out to at least 800m.

The new generation of cartridges, including the 224 Valkyrie, 6.5 Creedmore, 260 Remington, et al make good, long-range sniper calibers. But, with a light, skinny bullet, combined with a barrel with a fast twist-rate, we inherit rapid heat build-up, short barrel life, and the requirement for a long barrel. Significant muzzle velocity is sacrificed for every centimeter of barrel-length reduction. Thus, any of these calibers, in a short-barreled rifle (carbine), represents a contradiction of terms!

The first thing DOD is going to have to acknowledge is this:

When they really insist on a 500m rifle with acceptable penetration, that rifle will need at least a twenty-inch barrel and will have to be chambered for a cartridge with a bullet as least twice as heavy as that of the current 5.56x45.

Unhappily, what DOD has fanatically avoided confronting for the past forty years is the fact that they are going to have to, at long last, actually train real riflemen to kill individual enemy soldiers, one at a time, with accurate, semi-automatic rifle-fire.

I’m not at all sure they even know how anymore!

DOD could have an adequate main-battle-rifle, as described above, complete with appropriate optics, rails, etc, in the hands of front-line Soldiers and Marines in less than a year, all for a fraction of the cost of a single stealth fighter, if there were any will at the highest levels to actually get it done and finally put this issue behind us.

I’m less optimistic than I was a year ago!

/John
You can spray and pray or you can have an adequate battle rifle, but not both.
 
Don’t we hear that in most cases the firefight is within 75m or thereabouts? I get having a couple DMRs in the squad should it extend out, so are they being targeted from longer ranges now or what? I’m not on the battlefield so I have absolutely no say or conclusions drawn.

That said, if the military scales back on the 5.56, I will welcome cheap surplus with open arms.

This seems to be the only logical conclusion for now, since I doubt anything will change in the near future. A couple of .308's for each squad, and 5.56 for the rest.

I think they should consider .300 Win Mag for long range, or .300 WSM, but weight, costs, barrel life, etc. would have to be considered. What do I know?

I've heard the Marines are no longer teaching our guys how to shoot with iron sights. That is sad if true. Can anyone confirm this?
 
A 16 inch 6.8 barrel with a 95 grain projectile at 2900 fps. should be more than effective out to 600 yards. It is after all a 270 round. Beef up the material around the chamber and you can get a heavier projectile at those same speeds. Maybe a 110 or 115 grain projectile moving at those speeds would be devastating.deb
Introducing another round into the military is going to be like pulling teeth. The 5.56 and 7.62 being the standard rounds in the USA and most of the NATO forces is real sticking point for the introduction of a new round.
Sure snipers may get a little leeway and of course there's the 50 cal but that's used in other applications. It's going to take a very special debut for the military to even move it on to the next process which is endless testing in real world tactical scenarios.
It will be a up hill battle to say least. It will be years before we see a change. Unless they already have a clandestine round in the works.
 
Don’t we hear that in most cases the firefight is within 75m or thereabouts? I get having a couple DMRs in the squad should it extend out, so are they being targeted from longer ranges now or what? I’m not on the battlefield so I have absolutely no say or conclusions drawn.

That said, if the military scales back on the 5.56, I will welcome cheap surplus with open arms.
Damn right
 
so are they being targeted from longer ranges now or what? I’m not on the battlefield so I have absolutely no say or conclusions drawn.

One of the issues in Afghanistan is that the ragheads are firing from 600 yards out with left over Soviet bolt actions rifles. M15/M4 are ineffective at that range.

These aren't natives running through the jungle with spears, they have been continuously at war since 1870 or so. They can build a working rifle by hand from scrap metal. Point is they know a little bit about long range riflery.

In Iraq, they love in concrete blck houses the 5.56 can't penetrate. Lots different than shooting through wood studs and drywall. This has been a major concern of troops.
 
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