Structured barrels are a relatively recent development and interesting in and of themselves. One of the main objectives is to eliminate barrel harmonics that distort accuracy. The article didn't provide much info on the structured barrel used to break the record, so here's some from the only company I'm aware of that specializes in making them:<p><a href="https://www.thefirearmblog.com/blog/2019/07/30/tacomhq-structured-barrels-better-in-every-aspect/" rel="nofollow">https://www.thefirearmblog.com/blog/2019/07/30/tacomhq-struc...</a><p><a href="https://tacomhq.com/structured-barrels/" rel="nofollow">https://tacomhq.com/structured-barrels/</a><p>The Engineering Behind a TACOMHQ Structured Barrel: <a href="https://www.youtube.com/watch?v=C-7LKQYtU48" rel="nofollow">https://www.youtube.com/watch?v=C-7LKQYtU48</a>
Two quotes I thought were noteworthy:<p>> traveling at a downward angle and about 600 feet per second as they reached the target zone.<p>That is incredible. Some BB guns don't even fire horizontally that fast<p>> Regarding it taking 69 shots to hit the mark, with all the variables that had to be taken into account, “we were thrilled it was so few,” Humphries said.<p>To give an idea of how difficult this is....
Is this an engineering challenge or a marksmanship challenge?<p>Like... Could you just fire the gun, then put the target where the bullet went an fire again and say its mission accomplished because the real goal is just setting up a gun that stable and precise and deterministic?
Two interesting observations from this article:<p>* I am more amazed at the quality of the scope that the shooter could place a bullet on a 8" bullseye at a distance of 7.08km. There must be something fascinating to it since, Rayleigh's criterion for resolving two points puts some physical limits to the aperture. To resolve a palm sized mark, you need a sufficiently large aperture on telescope & that's not easy to mount/operate.<p>* This is one of the neatest images I have seen of the effect of rifling on the bullet, in addition to the thermochemical effect on the bullet tip. The tip at that distance & time of flight goes through sustained heating & there is some evidence of rapid oxidation - much like a piece of metal exposed for few seconds to blowtorch.
The design of the bullet itself is interesting. Normally, longer and thinner is more aerodynamic, in any fluid, air or water - it creates less turbulence and drag. But here they found shorter and fatter works better for transonic projectiles:<p><i>> The .416 Barrett cartridge is made by “necking down” a .50 Browning Machine Gun (BMG) round to accommodate the roughly .40-caliber bullet. It’s a relatively short, stout bullet that proved ideal for its purpose, Humphries said.</i><p><i>> “Traditionally in extreme long-range shooting, we wanted long, skinny bullets,” he said. “However, we discovered that as a bullet crosses over into subsonic velocity, it flies better if it’s shorter and fatter.”</i>
> “When a bullet is in flight for that long, you have to take into account the rotational speed of the earth. What you’re shooting at isn’t going to be in the same place it was 24 second ago when you pulled the trigger.”<p>Wow. Impressive work! I also noted the pitch differential between scope and barrel :O
This reminds me about the Ukrainian Snipex Alligator sniper rifle I read about recently. It uses 14.5-millimeter heavy machine gun rounds and it's claimed to be able to penetrate 10mm steel armor at 1,500 meters.<p><a href="https://www.popularmechanics.com/military/weapons/a41283557/ukraine-snipex-alligator-sniper-rifle/" rel="nofollow">https://www.popularmechanics.com/military/weapons/a41283557/...</a><p><a href="https://snipex.com/alligator" rel="nofollow">https://snipex.com/alligator</a>
> “The bullet is coming down so slowly, and at about a 48-degree angle, it was just penetrating into the ground without kicking up dust.”<p>I have no shooting experience, but the arc they have to put into the shot to travel 4.4 miles (~7 km), seems so counter-intuitive to what I associate with shooting. Really impressive work by this team, to have all this calculated out so that they can hit it within 69 shots.<p>I'm really curious what the success rate of their shot is. From the video, it sounds like the unsuccessful shots were still relatively close by, enough that they seemed confident in being able to still guide it in, so around 1/100 sounds about right, as a crude prior estimate.
104 years ago the <a href="https://en.wikipedia.org/wiki/Paris_Gun" rel="nofollow">https://en.wikipedia.org/wiki/Paris_Gun</a> could shoot 120 km (75 "miles", in medieval units), but it definitely couldn't hit a 200-mm target. Not even in 69 tries. (Yes, it was rifled.)<p>To me it seems like a more sensible way to hit a target from 7 km away would be to guide the projectile with movable canards, like the VAPP (or, as mentioned elsethread, the M982 Excalibur or XM1156 PGK). You could even do this with a bow and "arrow": once the "arrow" has gained 300 meters of altitude, it has a range of 7 km if its glide ratio is 24, quite achievable (though a regular arrow has a glide ratio of about 0). And you don't have to shoot it straight up, so you can get by with an even lower glide ratio than that.
Long range riflery is a wicked fun hobby if you're into engineering and/or physics at all.<p>The hardest part is finding a range that lets you shoot past 300 yards, is near your house, and doesn't require a pricey membership!
<i>A</i> shot?<p>Not to detract from the calculations and physical adjustments required to even get close, but a single bullseye at any other range doesn't impress. It's the grouping, three or more on top of each other.<p>To maybe detract, this was the 69th consecutive attempt. Hmm.
We used to break distance records in video games. The shooter would fire a shot and the spotters moved the target to where the shot landed then the shooter would fire again. Managed to get some amazing distances that way and break the game.
> it was nothing short of miraculous for the shot, the 69th attempt that morning, to land inside an 8-inch orange bullseye.<p>Magical even to me. But statistically, if you try often enough?
On the 60th or more shot is not a record, if you throw enough lead down range in the general aim, one will impact eventually.<p>Something like a 2km repeatable shot done with 338 lapua and 26" barrel high accuracy rifle is much more real world.
Not trying to downplay this. But with 69 shots, isn't this like Worms computer games where your first shot is guesstimate, and the rest is just nudging the degree "up or down"?<p>Or they use same approach that NASA uses to launch a rocket to ensure it lands on the moon? I.e some sophisticated calculation (which I assume part of the “some secrets” mentioned in the article).
"“It’s a one-in-a-million shot. They said it’s not statistically repeatable,” he said."<p>So it's like they're admitting it's almost a fluke, and I appreciate how they're being so upfront about that. They made a follow up video about how it's more like YouTube basketball world records than competition level ones. But still a great achievement.
I would love to see super slow-motion video of the bullet at the end of its flight to see how it’s spinning. It must be significantly slower than when it exits the barrel. Cue slow-mo guys.<p>Another very interesting thing to see up close and slow-mo would be the transition from supersonic to subsonic, but I have no idea how you’d even begin to get a camera set up to capture that.
I wonder how the sound would work?<p>I wrote a story where one scene had a rifle shot from just under a mile away. I don't shoot, and did what research I could under the deadline - characters heard the sound of the impact, and then the sound of the actual report shortly afterward. But I wonder if when it's that far away, if the report wouldn't have been audible at all.
Honest question:<p>Why does earths rotation matter?<p>You and the target are both moving at the same speed throughout the bullets flight in the same direction - why should it factor in?
It says it took them 69 attempts to hit the target. I wonder if that is repeatable, or did they just get lucky? The video gives the impression that the rifle was handheld, so they couldn't have dialed in shot like artillery. But if they had, what would the spread be like at that range? Would it even be possible to reliably hit the target? If not, is it literally just dumb luck?
> <i>“It’s a one-in-a-million shot. They said it’s not statistically repeatable,” he said.</i><p>> <i>... it was nothing short of miraculous for the shot, the 69th attempt that morning, to land inside an 8-inch orange bullseye.</i>
I just drew [1] the radius from my home for comparison, this is unimaginably far.<p>[1]: <a href="https://www.calcmaps.com/map-radius/" rel="nofollow">https://www.calcmaps.com/map-radius/</a>
I'm not saying it isn't impressive, but on the other hand... if you fire enough shots at something, you're eventually going to hit it. Where do you draw the line?
I used to think the movie “Wanted” was pure science fiction. Not anymore. It’s feasible someone could be sniped out from miles away. Must be a nightmare for security logistics of VIPs.
Not that I want to condone violence or assassination, but on reading this my first thoughts were "wow, that would make certain things possible that are currently difficult-to-impossible". And also "Day of the Jackal".
It’s mostly a pointless record however.<p>69 tries required to finally have the shooter put the bullet where the calculator said it should be.<p>Just mount the damn thing on a robotised arm, give it an anemometer, a military laser rangefinder and a stabilised camera, it will hit shot after shot. That’s pretty much what a small calibre artillery gun is with a slightly higher calibre than their rifle because why bother with such an inefficient projectile anyway.<p>And to be fair, at this point, given the extensive modification to the rifle, what they are doing is more or less turning it into a poor piece of artillery before shooting it in the worst way possible.