A mid-range sniper/anti-materiel rifle between the .30 and .50 calibers is optimal for some purposes. Cheyenne Tactical's .408 has been available for a while. Now, Barrett has introduced the .416. The question is: Which is better for what?
[LINK] Larry A question on biggerhammer.net
"Which shoots flatter between the two?" (.408 CT or Barrett .416)
Brent offered a comparison of the ballistics "on paper" (meaning from a computer program, using manufacturer claims):
I have the ballistics of both on paper @ 2,000 yds with 300yd zero.
.408 Cheytac .416 Barrett
Bullet wt. 419gr. 400gr
MIL drop -17.3 -12.9
Wind velocity 2.3 1.8
Velocity 1399 1686
Enery 1819 2524
Time 3.0 2.57
The discussion gets "interesting" from there. IF you're interested in ballistics, click on the LONG continuation.
My conclusion from it all: We need independent comparison tests.
In a Snipers Paradise article, John D. Taylor explains the designers of the .408 CT (Taylor and William Wordman) considered a range of calibers between .400 and .436, rejecting .416 because it's historically associated with the .416 Rigby, a hunting round:
"Existing 40-caliber projectiles such as the .416 were not considered because this novel caliber was to become associated with military usage rather than a caliber associated with big game hunting."
As noted, the Ballistic Coefficient (BC) BC varies with velocity
, and this variation is linked with the drag curve and the drag curve is linked
to bullet shape. Also, the drag curve varies with
atmospheric condition ( air density ..). So,
if you want to compare two bullets you must shoot them at the SAME
VELOCITY, shoot them in same weather and atmospheric condition at the
same altitude, and compare terminal velocity.
To
compare two rounds with different calibers, fired from different guns,
we need extensive independent comparison testing. This would be a great
project for a gun magazine, ASSUMING Barrett and Cheyenne Tactical/Lost
River would provide firearms and ammo.
I want to see comparisons at 500 yd, 1K, 1500yd, and 2K ranges (drop, drift, energy on target, penetration and physical damage in various materials).
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The clips below are from posts on the board. I've included them here as the board rolls on and is archived, so it might be hard for someone reading this a year or two later to find them. While somewhat argumentative, they do provide some insight, when absorbed all together.
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Lynn answered:
From the Barrett website they say 3250 fps with a .943 bc number.In order for the 408 Chey-Tac to shoot flatter it would need to either have higher velocity numbers or a higher bc number on its bullet.As it has neither a higher muzzle velocity nor a higher bc number on its bullet the 416 would win the flatter shooting contest.
When you want to compare cartridges to see which shoots flatter you need muzzle velocity and the intended bullets bc number.You can then go to the JBM Ballistics website or one simular and simply plug in the numbers.Velocity helps but if the bullet doesn't have a high enough bc number after a given distance all that extra velocity won't do you any good.
In the case of the 408 Chey-Tac vs 416 Barrett the Barrett has the velocity as well as the bc advantage so the conclusion is very easily in favor of the 416.
Triggerfifty, once associated with the CheyTac program, questioned Barrett's BC claim:
hhmmm, what doesn't make sense to those numbers is how you get a +.9 BC out of a .416 OD bullet that only weighs 400 grains, and is made of brass? Pardon me, having lots of experience in this particular field in the last 5 years, I'd like to see that bullet fly in front of a radar, not the published BC of a bullet for propaganda in a gun mag. Have seen this gun shoot, it didn't shoot too well. YPG not too long ago. Also, the faster you drive them, them faster they will slow down. Now, unless this .416 bullet is made out of a super dense material raising it's sectional density to a level of say... DU or a DU blend, hard to believe that a brass bullet gets a .9+ BC, wait, it only weighs 400 grains, did any one else NOT get the anamolies here?
Theory - BCs provided by factories.
Reality - Same bullets with downrange doppler radar data.
Case in point. 750 gr. AMAX - claimed BC of 1.05 or so, real BC is less than 1.00, closer to .9 than to 1.0.
Paper ain't flyin' and sometimes the numbers just can't add up. The .416 sounds "odd" looking at the numbers on the paper. I ain't buying it, would love to shoot against it though.
Lynn replies:
The bc number really doesn't matter as long as all the bullets are using a bc number based on the same method of testing.A bullet with a G1 bc number of 225 at 3000 fps will outfly a bullet with a G1 bc number of 180 at the same 3000 fps.
You raised the bc question again yet when you were asked about it several hundred times you never gave us any answers about your Lost River bullet.
How does someone get a .416 OD bullet weighing 400 grains to have a bc number of +.9 My best guess would be the same way someone gets a .408 bullet weighing 419 grains to a bc number of 1.0 as you now claim.The muzzle velocity off of the Barrett website is 3250 fps not 3500.
Triggerfifty:
Lynn, I am not associated in any way with lost river. They and myself are not part of cheytac any longer. The management of that company has driven some of the original owners out of the company with incompetence and HUGE incorrect claims. Cheytac, and I, in the old days would NEVER say a 1.000 BC bullet. That sounds like the senior VP, (you have to say senior or he gets mad), making typical BS claims. I walked. WHO is claiming a 1.000 BC? I really would like to know. Or is this internet inflational value in effect? I am not the greatest .408 fan right now. My own website is going to publish a real exposure of the .408. It is great for many things, it is NOT what they claim it to be right now and i steer guys away from the guns.
Triggerfifty:
... Yes, BCs constantly change, yes they plot like a sine wave. And Yes, Barrett makes tons of claims that aren't real or true. NO, you can't push a velocity up to make up for the BC. It will start high, but degrade much more rapidly than the same bullet launched at a slower speed.
Only BC that means anything is the supersonic average, minus the last 5% or range. You guys should spend about 50k per day on some doppler testing, you might learn something.
Lynn:
Dean
We don't need to spend $50,000 on a radar test as what you just said hit the nail on the head.We only need the supersonic data minus the last 5% and most won't even need that much.
DAN TEC (whose native language is French):
answer is for ?
there is thre phases ( aera ) in bullet fly
the supersonic fly where you can get serious and reliable information without the request of a dopler radar , G drag curve are available for most know bullet shape , these drag curve can be use from Mach 1.5 ( to avoid any mistake with Mach change following atmospheric condition ) to Mach 3.5 between this to Mach velociy curve is pretty a straight line
the transonic area which is as clear as a bottle of black ink , nothing is really clear and supersonic bang " affect a lot the bullet fly theory on balanced fligh need to be confirm too
the subsonic fly that the most easy area , curve is again close to straight line
SO
if you shoot from Mach 3.5 to Mach 1.5 that nothing difficult to calculate the BC and make all comparison you want /need or dream with just velocity muzzle record and target impact velocity
BUT
If you plan to shoot ultra long range you need to pass the transonic area and that became far more difficult to compute , only lock information is that some bullet sucess to pass the transonic aera without loosing all accuracy ( not all atmospheric conditions are record and surely air density affect transonic fly ) , some shooter in England or in the US country have sucess to shoot far ( 1 miles , 1.5 miles and 2 miles ) with Sierra SMK bullet launch with regular case /chambering
as Lynn write before to plan to shoot at X miles ( 403 miles LOL ) perhaps shooters need to get enought accuracy at 1 K and 1 miles and at 1K and 1 miles a lot of solutions are already available without to go the NASA to order a rifle .
Sale or make adds for 2500 yards rifles or cartridge is the same to sale truck with 750 HP engine to go to your closest supermarket that perhaps fun but nothing really usefull , I far prefer more reasonable products and use them ore , at this time a good quality 0.50 cal rifle with proven match bullet can reach 2000 yards and I doesnt know a lot of shooters who shoots the 2000 yards each sunday norming and less who can access to 2 miles range .
good shooting
DAN TEC
DAN TEC again:
before to start to fight with my bullet BC is better than your bullet bc
BC vary with velocity , and this variation is link with drag curve and the drag curve is link to bullet shape and drag curve is in Mach so mach value vary with atmospheric condition ( air density ..)
the only serious buller maker is Sierra because they publish 3 BC value ( one by velocity range ) other BC value are give following G1 table but any long range bulet ( boatail with tangent or secant ogive ) match at 100% with the G1 drag curve
so the common BC following G1 curve is just usefull to compare bullet at medium range and perhaps more to publish free commercial adds as Hey shooters look at my new magic 0.99999 BC bullet
only serious and available test is velocity record at the muzzle and velocity records at the range , after you can compute your BC value for
this range
this weather condition ( mach vary with weather condition )so IF you want to compre two bullets you must ( condition )
shoot them at the SAME VELOCITY
shoot them in same weather and atmospheric condotion
and compare terminal velocitythe highest velocity is the winner and with your record velocity you can compute your BC follwing the right G curve ( G7 ...)
othet way is Dopler radar but that costly and post computing request specialized softaware as PRODAS
a simple side by side comparaison is enought for civilian use and as refernce a simple mil specs bullet as the M33 in 0.50 cal is a nice tool because mil specs bullets have a lot of data and military have spend $$$$ in test for them
good shooting and have trust in only techical facts
DAN TEC
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