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Has anyone out there heard of this .40 cal. beast? It literally dwarfs the venerable long-range performer, the .338 Lapua magnum and is supposed to be more powerful than the .50 BMG out past 700 yards, with less recoil! Personally, i wouldn't want to be on either end of this monster when it went off! Any knowledge, or experience, out there?

Oh, by the way, the rifle that fires it is a rechambering of the .50 caliber Windrunner takedown sniper rifle.
 

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Unfortunately, the only thing I've heard about it is from what I've seen on the manufacturers website(and that material set off my Hype-meter for some reason) and some "exclusive" testing performed by a few writers.

It's one of the things where I'd really do the testing first.

Nekekami
 

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Its a great round

I would definatly get one but right now the only company really chambering it is for the windrunner rifles and I have never been a big fan of those.

Windrunner is going to be making a convertable that you will be able to shoot 338, 408, and 50 bmg. Shound be out in the next month. Sure does look like a great gun though.

 

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I've never really thought of the .40 calibur as a rifle round, but when you think about it it's not a bad idea at all. More punch than the .308, more accuracy and less recoil than the big .50 and a longer effective range. Brilliant!

Does anyone lnow whether it's a round nose or a spire point round?
 

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ironman said:
Does anyone lnow whether it's a round nose or a spire point round?
See pic above^^^^^

those are 408 rounds. If you have ever held one they are some of the meanest looking bullets I have ever seen.
 

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FLEA:

It is a SABOT round. It is a heavily modified Winchester SLAP. Slightly lower velocity, but heavier projectile. It is the issued sniper ammo for Swedish snipers, and effective range for our PSG90's has been extended out to around 1200m at most. And it cuts through vests better than many heavier rounds. But we're digressing from the topic of this thread =)
 

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Nekekami,

I know its off topic a bit, but how has the accuracy been with these rounds? As I indicated on my psg90 page, reports have been of reduced accuracy, but the trade off was worth it. How has the accuracy been for you?

MEL
 
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Mel:

Oh, this is going to be a long post, but here I go....

First off, in practice, the trade-off only occurs at very short ranges(as far as snipers are concerned), i.e 150m and less. At 100m, an ok shooter will shoot 3cm groups, about the same as with the Swedish army standard 7.62x51(For machine guns, battle rifles etc). However, the high velocity and low retardation means that it will be less affected by wind, temperature, air pressure, humidity and distance and have a shorter time-to-target and flatter trajectory, so the further out your target is, the more accurate the subcaliber projectile will be compared to normal bullets. As an example, from basic practice for snipers: With normal ammo(including match grade), if you range your target at, say, 800m, you zero your scope for 800. The advice for how to zero correctly with the sniper round(translation of the swedish military name for it, Prickskytteprojektil) is to zero the scope to half the measured distance. So in the above example, I'd zero the scope for 400m if I were going to use the sniper round. Also, the ballistic calculations become simpler, since you don't need to pay the same extreme attention to wind, distance and such factors as you would have to with normal ammo.

Conclusion: In practical use, there's not much of a trade-off, other than that you have to prepare the shot differently.

Ok, now that's sorted out, on to personal experience.

My personal experience is that I'm more accurate with the sniper round than I am even with match grade ammo, and some of my colleagues feel the same way. Likewise, there are snipers that shoot better with match grade ammo rather than this.

I've had as low as 0.3MOA groups with both kinds of ammo with the edge going to the sniper round, and at long ranges, I prefer to use the sniper round if I have it available at the time. Under decent field-like conditions, 800-900m becomes a range where you can reliably and repetedly make lethal 1-shot kills, and you can be fairly confident that you will hit your target in the upper body at 1000-1100m range. If you're really good, and aim carefully, 1200m is not impossible. Some, like Magdalena Forsberg have even hit man-sized targets in the upper body at ranges beyond 1200m, in field-like conditions, but not reliably.

(Footnote/disclaimer: If you're in miserable condition, you will of course shoot worse)

Btw, the ballistic statistics linked on www.fmv.se and other places concerns the Winchester SLAP, and are thus inaccurate for the current breed we're using. They were used pre-purchase, to indicate what performance could be expected. But I'll post a link to one of the images, this one concerniing the difference in trajectory between the normal ammo and the Winchester SLAP:
http://www.fmv.se/images/Traject.gif

Nekekami
 

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Ok, could add some more:

The match ammo I'm comparing against(I.e the ones I occasionally use)
is:

Lapua Lockbase
Lapua FMJBT
Federal Gold Match(Might just be me, but I was kinda disappointed. I don't know, but I just didn't feel comfortable with it)
Handloaded(waste of time for me, didn't have any noticeable effect, not better, not worse. Besides, I can't get hold of the propellant Lapua, Raufoss and Vanäsverken/FMV uses)

Mel:

If you ever find Lapua Lockbase or FMJBT in a store and have spare cash, I'd recommend at least testing either of them. I like them a lot
 

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Nekekami,

Great report! Thank you for the info. It sounds like the current breed of ammo you are using is better then the original prototype. Its a very interesting concept that I have been following for a long time. I do appreciate your insite into it.

I have been anxious to try some lapua match ammo, now it sounds like I need to make a harder effort to track some down.

MEL
 

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Mel:

Yes, the current breed is indeed better.
Lower velocity, around 1260m/s but heavier(6.2g), with the same diameter, so retardation is even lower. Lots of kinetic energy too.
Most of the 1 million rounds ordered from Winchester in 1998 are placed in various weapon caches and mobilization storage.

V0 and Energy are at muzzle, any other distances would depend on external factors too.
Diameter of projectile is 4.81mm
Area of cross-section: Roughly 18.17 mm²

Original Winchester SLAP:
V0=1340m/s
Mass=3.4g
Energy=3052.52 joule
Energy/mm²=168 joule rounded up

7.62x51 Sk PTR10 Prick(T)
V0=1260m/s
Mass=6.2g
Energy=4921,56 joule
Energy/mm²=271 joule rounded up

As a contrast, here's the stats for the 7.62x51 SK Ptr10 PPrj (Swedish AP ammo)
Area of cross-section: 45.6mm²

V0=960m/s
Mass=8.2g
Energy=3778.56 joule
Energy/mm²=82.9 joule

Here's the Lapua .338 Magnum FMJBT Lock-base
Area of cross-section: 58.1mm²

V0=915m/s
Mass=16.2g
Energy=6781.5 joule
Energy/mm²=117 joule rounded up

On the other hand, the .338 Lapua Magnum has higher momentum than the other mentioned rounds, and a high weight compared to the bullet diameter, so its retardation is low too.
 

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OK, I've had a chance to read up on some Swedish forums, and a person in Finland commented about the .408 CheyTac. He's had an opportunity to testfire it, and his comment was that there's a lot of hype surrounding it. It's not bad, according to him, but it doesn't outperform the .50BMG, and it packs a hell of a lot more recoil than the .338 Lapua Magnum, so it wasn't really better. He also pointed out that the ballistics test that they have published involves their own precision bullet for the .408 while they tested against ordinary 12.7x99 M33 Ball. He did his own comparison with his handloaded 12.7x99, with 50g(773gr) bullets of Warren Jensen's, i.e Lost River's, own manufacture(The same company that makes the bullets for the .408 Cheyenne, btw...), and it outperformed the .408 Cheyenne in every aspect, and reaches a BC of 1-1.1 according to testing. He also commented about the .338 Lapua Magnum. In the comparison with the .338 Lapua Magnum, they used a 16.2g(250gr) Scenar bullet, when there are better bullets with higher BC's available, such as the 19.44g(300gr) Sierra Matchking available. He's personally reached 0.8BC.

So, it's pretty interesting when the company doesn't even dare to compare their .408 to their own 12.7x99 ammo.
 

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i have herd that this is some sort of 'super' rifle
419gr @ 2900 fps.. impressive but not in the .50 cals leauge
and the BC i heard .914, impressive too
saw one in my local gunshop at $18,000 so its way out of my price range and way to big to be useful for me
herd from a few people that the .408 Chey Tac holds all the long range shooting records, sub 5" 5 shot group @ 1536y which is damn impressive if its true anyone know about this?
 

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I've seen similar reports at various sites. In those articles they talk it up as a .50 cal. replacement. Similar useful range against man-sized targets, but much less recoil.
 

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I hav eben looking at the .408 and cheytech and i like what i see (good but lacking the wide varity of rifle choice's )I do how ever like one rifle in particular the M310 how ever this rifle is only a single shot rifle I personely would like to see a version of this rifle with eather an internal box or a removable box clip but as for the amo the one sme one had posted it is a sabbet round.
 

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I was thinking of building either a 338 Lapua or a 408 Cheyenne in my next tactial rifle but my problem is actions for both of these cartridges. Also which would yall think is better out of the 2. I a looking for a repeating bolt action not a single shot. The 50 is way to much in my opinion for what i would ever use it for. But they are about to open a 1200 yard range down the road from my house so u never know. Lata
 
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