this post was submitted on 30 Jun 2024
185 points (95.6% liked)

NonCredibleDefense

6623 readers
479 users here now

A community for your defence shitposting needs

Rules

1. Be niceDo not make personal attacks against each other, call for violence against anyone, or intentionally antagonize people in the comment sections.

2. Explain incorrect defense articles and takes

If you want to post a non-credible take, it must be from a "credible" source (news article, politician, or military leader) and must have a comment laying out exactly why it's non-credible. Low-hanging fruit such as random Twitter and YouTube comments belong in the Matrix chat.

3. Content must be relevant

Posts must be about military hardware or international security/defense. This is not the page to fawn over Youtube personalities, simp over political leaders, or discuss other areas of international policy.

4. No racism / hatespeech

No slurs. No advocating for the killing of people or insulting them based on physical, religious, or ideological traits.

5. No politics

We don't care if you're Republican, Democrat, Socialist, Stalinist, Baathist, or some other hot mess. Leave it at the door. This applies to comments as well.

6. No seriousposting

We don't want your uncut war footage, fundraisers, credible news articles, or other such things. The world is already serious enough as it is.

7. No classified material

Classified ‘western’ information is off limits regardless of how "open source" and "easy to find" it is.

8. Source artwork

If you use somebody's art in your post or as your post, the OP must provide a direct link to the art's source in the comment section, or a good reason why this was not possible (such as the artist deleting their account). The source should be a place that the artist themselves uploaded the art. A booru is not a source. A watermark is not a source.

9. No low-effort posts

No egregiously low effort posts. E.g. screenshots, recent reposts, simple reaction & template memes, and images with the punchline in the title. Put these in weekly Matrix chat instead.

10. Don't get us banned

No brigading or harassing other communities. Do not post memes with a "haha people that I hate died… haha" punchline or violating the sh.itjust.works rules (below). This includes content illegal in Canada.

11. No misinformation

NCD exists to make fun of misinformation, not to spread it. Make outlandish claims, but if your take doesn’t show signs of satire or exaggeration it will be removed. Misleading content may result in a ban. Regardless of source, don’t post obvious propaganda or fake news. Double-check facts and don't be an idiot.


Join our Matrix chatroom


Other communities you may be interested in


Banner made by u/Fertility18

founded 1 year ago
MODERATORS
 
you are viewing a single comment's thread
view the rest of the comments
[–] sp3tr4l@lemmy.zip 17 points 4 months ago* (last edited 4 months ago) (3 children)

Could keyholing of ... seemingly this magnitude... be the result of basically laughably bad tolerances in internal barrel width, or perhaps the barrels are made of some kind of alloy that expands significantly from heat?

I have only ever seen keyholing in western gun videos from basically burn downs... but even then after a barrel is nearing its end of life by manufacturer specs, its more common to get some kind of failure to feed, significantly decreased precision and only occasional keyholes.

Maybe another possibility is similarly poor quality alloy of some kind used in the cartridge itself?

Combination of all of these things?

I remember seeing a fairly recent video of some kind of PLA MOUT type urban course... and you could see massive keyholing on targets that were like 5 to 10 meters away.

The prevalence of it baffles me. Ive personally dealt with and seen misfires and jams of various kinds at ranges, but I've never even seen a keyhole occur in real life.

[–] shalafi@lemmy.world 13 points 4 months ago (1 children)

I've seen a .22LR of mine keyhole. Once. Or twice. Ever. I honestly thought this was an AI imagine making fun of the PLA.

[–] frezik@midwest.social 5 points 4 months ago

I saw it at the range a few times. Worst was when someone had their scope set way too low, and it was causing them to hit the concrete roof. Let off three shots, wasn't even on paper, and then the next one keyholed. Hold up here, let's twist this knob and try again.

[–] Milk_Sheikh@lemm.ee 6 points 4 months ago (1 children)
[–] commandar@lemmy.world 3 points 4 months ago (1 children)

Fleet yaw is a different phenomenon that impacts terminal ballistic performance. It's essentially a way of describing why some projectiles tumble and fragment after impact while others will tend to remain more stable and pass straight through for longer.

The projectile AoA being described in that context is only a couple of degrees. It's enough to change how the round behaves after hitting something, but it's not the type of in-flight wild tumbling that results in keyholing on a target.

[–] Milk_Sheikh@lemm.ee 2 points 4 months ago

This is an important clarification, you’re right. The yaw angle is minimal in ballistic flight, the level of keyholeing in the photo is rather dramatic. Though the 5.8x42mm is standard with a mild steel penetrator like M855, and the round was definitely built with cost as a major factor - maybe a bad lot of ammo?

[–] FireTower@lemmy.world 5 points 4 months ago

On the heat issue prolonged fire would cause the metal to soften allowing for increased degradation of the rifling.

The easiest ways for it to happen would be either a poorly made barrel or a barrel not designed for a specific projectile. Different barrel twist rates are better for different cartridges. A heavy bullet is better in a faster twisted barrel. If you fired a very heavy bullet in a slow twisted barrel you would likely not have it reach a proper stabilization.