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Military Guns and Ammunition

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This is intended for people interested in the subject of military guns and their ammunition, with emphasis on automatic weapons, particularly in larger calibres (12.7+mm).

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Exploring The Design Space   Ammunition <20mm

Started 25/7/15 by NathanielF; 101079 views.
QuintusO

From: QuintusO

20-Jun

poliorcetes said...

 

How do you calculate frag range? just speed or do you add up another variables?

 

I may do it in a couple different ways, furthest distance to 1,700 ft/s or 1,900 ft/s or 2,100 ft/s depending on the kind of bullet, and usually with small caliber stuff like that, I'll limit it to furthest distance to 720 J. Looks like I didn't do that for that chart, though.

QuintusO

From: QuintusO

20-Jun

Not 100% happy with the math I used for this analysis, but I am losing interest so might as well post it:

QuintusO

From: QuintusO

20-Jun

BTW, if you want to execute this concept correctly, you need to start thinking in terms of duplex or triplex ammo, as that dramatically increases the bullet-in-magazine density.

And yes, I've explored this idea too:



Including some basic studies on firing mechanism.

The big challenge is the barrel, which must have either three bores in very close proximity, or the ability to rotate a cartridge to line up with the bore at very high RPMs.

QuintusO

From: QuintusO

20-Jun

This is my current favorite proposal: .224 Valkyrie with the COAL increased by forty thousandths of an inch, and the MAP increased to 5600 BAR, and loaded with the Mk3 VKO. The additional COAL enables finer bullets while making sure most of the time you can't chamber the overpressure rounds in regular chambers (which aren't in abundance anyway). Note that the 5600 BAR limit does not impart much of a kaboom risk, but it does impart a stress risk, i.e. bolts will break too soon if you fire a steady diet in a rifle not rated for that round. Difficult to do that if the magazines physically do not fit in the wrong rifles.

What's the point in keeping the original chamber spec? Good question. I have considered several times alternate specs that would prevent the rounds from being chambered at all in existing .224 Valkyrie chambers. I do not believe those solutions make sense. If you're going to do that, you might as well go neckless, which is another idea certainly. But this one has a pathway. I can start empirical work on it for $500 smackaroos. Most of the failure modes are graceful. Performance is great all around (it smashes all the GPC metrics). 

QuintusO

From: QuintusO

26-Jun

I promised you the briefs on Hellcat and Archangel, but work was busy and I had a few days of passing out almost immediately after coming home. But I've finally remembered, so here they are.

A note. The Archangel brief was written before Archangel was designed. It was a pitch to a company that I will not name for me to design the gun. They declined, and I designed it anyway. Nobody ever said I was a great businessman, hahaha. But it gives you a great idea what my goals and thought processes were when designing that gun.

The Hellcat brief was written at the end of 2019 because a lot of people were asking me to bring them up to speed on my projects (Hellcat being then current). The brief includes a basic summary of Hellcat as well as the other guns I had designed to that point. 

Archangel Rifle Proposal: https://mega.nz/file/r99gBIhQ#9uE1EAakgZ7O8GznYJ7srrDPPgMFAgOos8_ysIMRy84

Project Hellcat Brief: https://mega.nz/file/CstAWI7A#387un4wX6KXcvn7q9aMY8GYE4joxck0QOE-Mu4k5wL4

poliorcetes

From: poliorcetes

30-Jun

Thank you, Nathaniel. Would it be also possible to check the renders you posted time ago about archangel and hellcat? 

QuintusO

From: QuintusO

30-Jun

Check them? Not sure I understand.

poliorcetes

From: poliorcetes

30-Jun

View them in detail?

QuintusO

From: QuintusO

30-Jun

View the screenshots in detail? Knock yourself out.

poliorcetes

From: poliorcetes

30-Jun

I meant, just like here in the forum but without site search using google or bing. 

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