From the White papers on the 408 CheyTac ® Cartridge:

Too large to post in full here in its entirety but will e-mail to anyone interested.


2. . The Ammunition The CheyTac® Cartridge was developed to fill the gap between the 338 Lapua and the .50 BMG, yet the downrange characteristics outperform the best .50 BMG projectiles. The projectiles are manufactured by Lost River Ballistic Technologies™ and are designed using PRODAS software. The projectiles are CNC, lathe turned,projectiles of a copper/nickel alloy. The 419grain projectile has a supersonic range of 2200 yards+ at standard air conditions. A second projectile is available - the 305grain projectile is designed for a high velocity near range application. The average ballistic co-efficient of the 419 projectile is .945 over 3500 meters..........

........... The CheyTac® LRRS as a Soft Target Interdiction System
The CheyTac® LRRS is a solid anti-personnel system to 2000 yards. The primary intent
of the .408 is as an extreme range anti-personnel system. Groups of 7” - 9” at 1000
yards, 10” at 1500 yards and 15” at 2000 yards have been consistently obtained. Groups
of 19” at 2100 yards and 29 “ at 2400 yards have also been obtained. All groups that are
up to 3000 yards are less than 1 minute of angle for vertical dispersion.......

.........The CheyTac® LRRS as an Anti-
Material Rifle3
The high remaining kinetic energy
characteristics of the 419grain projectile make it a very effective anti-material rifle. The .50 BMG has a higher initial muzzle energy of 11,200 ft. lbs. vs. the 408s energy of 7,700 lbs. At 700 yards however, the remaining energy of the 408 is higher than that of the .50 caliber rifle. Ranges past 700 yards are the realistic engagement-range for antimaterial rifles.....

The .408s 419grain projectile will defeat any material that the .50 BMG can defeat except those targets that require an explosive projectile. While the round of choice is the Raufoss for anti-material operations, there is a strong argument for use of solid projectiles for many of the material targets. Material targets such as surface to surface missiles can be easily engaged and defeated by the use of solid projectiles......

.......The CheyTac® Long Range Rifle System provides an outstanding value proposition. Loadedcartridges are priced at the 338 Lapua level. Additionally, loaded cartridges are much lighter than the .50 BMG cartridges. Four 50 BMG cartridges weigh 1 lb. while 7 .408 cartridges weigh 1 lb. The operator level maintenance of the entire system, including barrel replacement, provides logistical efficiency. Barrel replacement is as simple as calling CheyTac® Associates, LLC and ordering replacement .408 barrels......

Advantages of the .408 CheyTac®
cartridge over the .50 BMG cartridge
include:
• More compact
• 33% less weight
• Greater kinetic energy (beyond 400 yards)
• Shorter time to the target
• Greater velocity to the target
• Superior accuracy
• Engages targets at greater distances
• Remains supersonic longer for greater accuracy
• Less primary recoil due to lighter projectile
• Greater raw materials savings in manufacturing.

Advantages to the US Army of the CheyTac® rifles over the .50 BMG rifle include:
• Greater choice in rifle designs to fit combat missions
• Suppressed noise for silent shooting
• Requires less training than the bullpup design
• Ergonomically easier to shoot,thus improved accuracy
• Two turn-bolt receiver designs gives superior accuracy compared to a semi-automatic receiver design
• Greater reduction of secondary recoil (Advanced muzzle brake design)
• Does not expel gases into shooters’ eyes (Advanced muzzle brake design)

Powerful;
Note: The .50 Raufoss cartridge was designed as an improvement over the .50 Ball cartridge.
Data indicates that kinetic energy profiles are very similar.

The .408 CheyTac® kinetic energy surpasses the .50 Ball and the .50 Raufoss at
approximately 400 yards and maintains the lead beyond 2500 yards (1.42 miles).

In supervised tests, the .408 CheyTac® projectile penetrated armor and laminated glass
that was resistant to the .50 BMG projectiles (US Armed Forces Journal, August 2003)

Faster;
Note: The .50 Raufoss cartridge was designed as an improvement over the .50 Ball cartridge.
Data indicates that kinetic energy profiles are very similar.
At 1000 yards the .408 CheyTac® projectile exceeds the .50 BMG projectile by
approximately 1 second and at 2500 yards (1.42 miles) by approximately 1.5 seconds.

More Stable;
Note: The .50 Raufoss cartridge was designed as an improvement over the .50 Ball cartridge.
Data indicates that kinetic energy profiles are very similar.

The .408 CheyTac® projectile was designed to penetrate the atmosphere with the least
amount of resistance. It remains supersonic to 2400 yards, while the .50 Ball and the .50
Raufoss projectiles remain sonic to only 1700 yards.
The .408 CheyTac® projectile remains stable as it passes through the transonic zone and
remains on its original trajectory path (Patented Balanced Flight Process). However, the
.50 Ball and .50 Raufoss projectiles undergo extensive vibrations through the transonic
zone, resulting in their departure from their original trajectory paths.

Impressive or Awesome not sure which!

Great round but doubtful it will replace the 50 BMG. First, it is a special application sniper round with (at the present time) only one bullet for one purpose. At 400 grains, it can't be configured in APTI or HE and carry enough compound to be effective. OTOH, a 50 BMG with a sabot can carry a bullet similar to the 408 to similar effect. The 50 has so many different capabilities it will be a quite a while before something manages to replace it.

The 408 CheyTac, and the 416 Barrett are better long range anti personal rounds than the 50 BMG.

But the 50BMG is much better for shooting STUFF.

And it does OK on people as well.

I had not heard of sabot rounds in the .50 BMG. I expect the results would be pretty spectacular.

You betcha! 30 caliber tungsten projectile at 3985 feet per second. They were developed in the 80's to defeat more armor (2 to three times more than standard AP at any given range) and against armored aircraft.

They are called SLAP or SLAPT (tracer) and serve a different function than the 408, very effective and they function in the M2 in full auto nas well as dedicated rifles. Doubtful if they can be shot as accurately as the 408.

You cannot shoot SLAP rounds through a 50 with a baffle type muzzle break.

It is also recommended not to shoot any "man portable" 50 rifle without a very good muzzlebreak.

I do not think any type of just barrel porting would reduce the recoil enough on a 50 rifle.

Some 50s are now braked with KDF type brakes. Their effective recoil reduction is a function of length relative to caliber. I do not know if that makes a difference in your point; I do know that sabots and brakes can be bad ju-ju. But the thrust of the question was whether the 408 would replace the 50 BMG and I assumed that was in military applications in general, not limited to dedicated sniper rifles. Could have been a poor assumption.

From what I understand you cannot shoot SLAP ammo in a KDF type brake either.

It would have to be something like Magna Port, where the "holes" are not larger than bore diameter.

Nothing under the 50 BMG can replace it for "STUFF".

At least with present technology.

FYI- I've shot a .408 Cheytac bolt gun vs yours trulys .50BMG light class bolt gun with yours trulys own 800gr,.50BMG bore Riders at 1000yrds into a steady 7-8 mph quartering wind off the bench,with bags. The .408 Cheytac did a best of 1MOA while my bolt gun was .6MOA. average of 3 5 shot groups each gun. I gave them both my best efforts as I thought I'd be impressed by the Chey Tac. Dont think I'll be moving in that direction anytime soon.-Rob

Here's a real live Winchester SLAP round:
0.303" Tungsten (Not Tungsten Carbide) Penetrator
360 grains.
.
.

.
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It goes pretty well. I wondered how that hard plastic would grip the tungsten so the rifling would have some effect and found a small square of aluminum in the Sabot. My theory is when fired the aluminum deforms and grabs the bullet by the notch on the bottom. my $0.02

On the Chey Tac... the "installed Base" on the BMG is too large. When the BMG becomes outlawed I'm gonna get a 458 bbl for mine.

For a Laugh, go here...
http://forums.accuratereloadin...=489105786#489105786
Don't shoot a Steyr without a brake!

For Velocity with sabot, RBCD has an incredible combination. 200gr 30 caliber bullet, sabot of unknown material MV: 5900fps

Andy B

Don't rule out the Raufus HE round loaded for the 50.

408CT's are being rebarreled/necked to 375 for available projectiles.

The .50 BMG will no more be replaced by the .408 Chey-Tac or .416 Barrett, than the .45 ACP will go away because of the .45 GAP. It has a strangle hold on availability because it is a military round. On paper the high performance .408's and .416's look better, but that alone doesn't sell cartridges. These specialty rounds are hard to find ammo and components for, and will remain that way because of limited sales. .50 BMG rifles and ammo, while expensive, are still within many shooters financal framework. Bill T.

The 408 and the 416 50 based rounds well catch on in places that out law the 50 and with a few shooters looking for a very good long range round.

the milltary has found the 50 to be a very good round.

It certainly will in states with .50 BMG bans like California.

quote:

It certainly will in states with .50 BMG bans like California.

No, that is why we have the 510 DTC.

It's not going to help me when NY bans .50 Cal and doesn't specify BMG. I still think I'm gonna work up a .458 BMG (one Day)

How about we start a new round the 499 Pelosi.