A Physics Primer

[tark]

Nom de Forum YOU TOO? I am 65 and this is my first computer. MY son had to drag me kicking and screaming into the 21st century. I don't know how to post a picture, but I will learn.
Getting back more to the subject of this thread, I have a son (California Kid) who knows some pretty high powered people. These people have Doctoral degrees in subjects like Thermodynamics, Nuclear Physics; things like that. They work at Lawrence Livermore National Laboratories designing and building nuclear weapons. I had my son put Tuners premise to them . The one saying if you plug the bore on a short recoil gun, nothing will move, whereas a blowback will eject the case and will cycle

Guys, on that one point, Tuner is correct, it may blow up the gun, but that slide will not move. And that explains to me why all the blown up 1911s that I see in our shop always have the slide fully forward and in battery. I disagree on whether or not you will wreck the gun, Tuner, but you are right on that point.

 

[RX-79G]

Tark, that wasn't Tuner's point, and no one would have disagreed if it was.

Tuner said the recoil pistol wouldn't cycle with the breech sealed. Which it will.

 

[tark]

Tuner said that if you could render the bullet immovable,and fired the gun (short recoil gun) that nothing would move. He was right. I still think the brass from the blown out case , the mangled magazine and the shredded grips would be moving but Tuner and I can agree to disagree on that. I know he argued about what would happen if you sealed the breech behind the cartridge, or load, or whatever, but I haven't had any time to present that question to my son's scientist friends. I will show this entire thread to them when I visit my son in the spring, along with the previous thread about short recoil that started this catfight. I will be most interested to hear what they have to say. I will bribe them with a few of the Cuban cigars that seem to fall out of the sky from time to time...

 

[tark]

I believe nomdeforum is referring to the Webley-Fosbury (Did I spell that right?) revolver in 455 Webely. Damn it , that doesn't look right....but you know what I mean.

 

[45_auto]

I believe the point he's making is that you could also make a spring loaded or magnetic cartridge that would launch a bullet without gas that would cycle a blowback gun

Could be. Still doesn't make a 1911 any kind of "blowback" or "delayed blowback" action.

And the locked breech, recoil operated pistol is technically a delayed blowback.

The quote above is what started the whole discussion about a welded-breech 1911. He still doesn't understand why it would work, and the difference between recoil operated and blowback.

No big deal, his posts are hilarious. Gives me something to do when I'm bored!

 

[45_auto]

Is there anyone here that seriously believes that a plugged bore is the same thing as a closed breech? Hopefully everyone realizes that a plugged bore is FORWARD of the projectile, while a closed breech is BEHIND the cartridge case head?

 

[Nom de Forum]

I believe nomdeforum is referring to the Webley-Fosbury (Did I spell that right?) revolver in 455 Webely. Damn it , that doesn't look right....but you know what I mean.

Well, I know it’s a stretch, but here it goes:

The barrel and slide are one part at the moment of firing and remain so while the breech block moves backward - so not blowback

The barrel recoils a distance shorter than the cartridge - sounds like short recoil so far.

The barrel breech lock recoils with the barrel and does not remain fully out of battery while the barrel moves forward - so not long recoil.

You got it, I am cheating with the Webley-Fosbury Revolver. You have to manually load all the chambers before firing so it is not self-loading. You have to consider the barrel as consisting of two parts, rifled section and multi-chamber breech. After the barrel recoils to its farthest point an “empty” chamber unlocks and a loaded chamber locks as the “slide” moves forward.

You guessed it, Tark, but to be fair RX-79G was the first to suggest something similar.

Be nice RX-79G in your explanation of how I am technically wrong, I am just having fun.

 

[Nom de Forum]

Is there anyone here that seriously believes that a plugged bore is the same thing as a closed breech? Hopefully everyone realizes that a plugged bore is FORWARD of the projectile, while a closed breech is BEHIND the cartridge case head?

Why did you post a belted cannon cartridge diagram? What is it? I have a 20mm Lahti round on my shelf and I know it is not a diagram of that. Is it just a non-specific example?

 

[Jlr2267]

45auto,

I believe the point he's making is that you could also make a spring loaded or magnetic cartridge that would launch a bullet without gas that would cycle a blowback gun, so using a similar example of gasless function in a recoil gun doesn't prove anything.

And he has a point. The examples only started to come up when the welded breech came up. The definitions of these terms are concrete enough, but some of the misunderstandings could only be addressed with examples of what isn't happening

That was indeed my point, and in just a couple sentences, you've made it better than I was able to in several posts.

 

[TimboKhan]

And, because you guys can't understand the concept of not being snarky, this one is getting closed to.