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Comment by rthomas6 | Hacker News Reader

I'd just like to point out something that nobody has addressed so far, which is that this setup triples the accurate range of the rifle compared to a human operator. That is absolutely astonishing. If the accurate range increase would apply to larger caliber rifles, this means that with a .50 sniper rifle, it could be used to snipe targets almost a mile away. It wouldn't even take a human sniper being in position.

...In fact, the $17,000 price tag is probably cheaper than training a human sniper. I'm sure we'll see this in military use in the next 20 years.

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This system in no way triples the effective range of these rifles. The "error budget" analysis in the Army Research Laboratory report is purely estimated; it's not based on real world observations. Unless I'm reading it wrong, the error budget analysis is pure fiction.

Take the hit percentages from Table 5 for the .300WM - they claim a baseline hit percentage of only 34% at 600 yards which is ridiculously low. I've directly observed marksmen shooting the (far inferior) .223 cartridge at 600 yards with open sights at one of the more difficult ranges in the U.S. With no spotting, hit percentages are consistently close to 100%.

We see snipers in operational environments getting kills at over a mile with a .338 Lapua - one of the longest was 2600 yards. According to this report, that sniper would have had only a 4% chance of making the shot if is was 1000 yards closer.

I don't see any way to rectify what we see in the real world with the conclusions from this report.

> I'm sure we'll see this in military use in the next 20 years.

The individual technologies in this new integrated scope have been available in dedicated spotting scopes for years. The advancement here seems to be packaging it up into a single weapon-mountable scope. I don't think there's a whole lot of value add for this setup for the military over the separate spotting systems currently in use.

Yow, if you're reading that correctly, then no one should be bothering to buy .338 Lapua rifles, since their whole point is to get reliable results beyond the 800-1200 yards you can in theory get from .30 envelope rounds like .308/7.62 NATO and .300 WM, but without the gross overkill of .50 BMG, which was intended for a material destruction role, not anti-personal.

Right, yet in real life we see effective use of those rounds out to double that 1200 yard range.

And, of course, accuracy is only one part of effectiveness. Stopping power is also important, especially in the military role, and varies greatly between cartridges; for instance .338LM is something like 5000 ft.lbs. at the muzzle vs. .308 which is somewhere around 2900.

Regarding .50 BMG - I'm not sure there is such thing as overkill if you're one of those guys on a two-way range. ;)

Heh, but with 63% more muzzle energy than .338 LM ... well, I don't have to tell you this, but for the larger audience we're talking about a heavier weapon and more recoil, a lot more muzzle blast (more likely to be observed by the enemy), the rounds are heavier and bigger (pxlpshr has a point about the impracticability), etc. etc. Snipers have used it mostly because it was available, not because it was well suited for the purpose. And of course sometimes they're called upon to ... discretely destroy material.

They haven't caught on yet, but Barrett and others have been working on cartridges with 400 instead of 600 grain bullets and noticeably less energy: http://en.wikipedia.org/wiki/.416_Barrett#Muzzle_velocity

I thought the .416 Barrett was basically designed to get around laws that explicitly prohibit .50 BMG, rather than to be a superior alternative. (It's possible I'm thinking of .408 Cheytac here though.)

Partly, but since Barrett has a firm policy of not selling to jurisdictions like California that ban civilian use of .50 BMG only so much. It's also intended to be a superior alternative for the non-material sniping role,

All very good points. I don't really follow wildcat cartridge development, but the .416 does look like it fills a gap.

Not at all clear except on calm days; all my readings about sniping and very long range target shooting talk about the need to read the winds way beyond the location of the shooter. Long target ranges have flags at intervals, snipers have to learn how to read it from vegetation movement and so on.

Interesting. I suppose at such long distances one can no longer assume that wind speed is the same at the target's location. I wonder if tech like this could be made to also read wind speed from vegetation movement?

I shoot service rifle at 600 yards on a range with wind flags at 100 yard intervals. It's not uncommon at that range for the wind to be blowing in opposite directions at each interval. At that range you can make an accurate read on the wind speed at the target purely from the mirage, reading vegetation movement is not necessary.

My understanding is that down range wind sensing systems do so by reading the mirage as well.

I don't know if it is the same thing that you are alluding to, but LIDAR can be used to measure distant wind speeds. I don't know if the output would be suitable for shooting, but it has been used in sailing.

https://en.wikipedia.org/wiki/LIDAR#Meteorology_and_atmosphe...

http://optics.org/article/34878

http://www.gizmag.com/catch-the-wind-racers-edge-laser-wind-...

That's cool stuff. Seems like it could be useful if it could be miniaturized.

ETA: The binocluar device in the last link is pretty close, if they can extend the range from 300m and drop the price tag from $150K!

... assuming it works as well as this PR piece suggests. But even if it doesn't, the tech will certainly evolve to something incredible in the next 20 years.

You are exactly right.

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