Internal vs. External bolts

[Fresnel]

I noticed the other day that I've never seen a pistol with a fully internal bolt mechanism. I don't count AR pistols in this though, because those really aren't pistols IMO, they're just tiny rifles. If you watch any semi-auto handgun fire, A large potion of the external shell moves in order to cycle the round. I'll include a picture here because I have it, and it is awesome.



Notice how the slide racks back. Right. Now take any semi- or full-auto rifle. No real portion of the external shell moves at all, only the bolt itself and anything directly attached to it (e.g., a cocking handle). The same is true with an SMG. Why is this? Why are there no pistols with entirely immobile exteriors?  

[OberFeldwebel]

They would be too bulky?  

[Man of the Demoneye]

My best guess would be the amount of available space that the gun takes up. In a rifle / shotgun, you can take as much space behind the reciever as you need (within reason). On a pistol, you are trying to keep it as compact as possible.

Again, best guess.  

[Fresnel]

Man of the Demoneye

My best guess would be the amount of available space that the gun takes up. In a rifle / shotgun, you can take as much space behind the reciever as you need (within reason). On a pistol, you are trying to keep it as compact as possible.

Again, best guess.

It can't be any bigger than a DEagle. I'm wondering if it would be possible to make a gas-piston pistol... It'd be far more conducive to mounting a small scope on, and the sights would have zero drift from slide wobble. I should draw this up sometime. I wish I had CAD and knew how to use it. sad  

[ArmasTermin]

Weight must be one issue, scopes being another. Mounted optics on rifles are closer to the face than they are on pistols. You don't want a slide on a rifle pegging you in the cheek. So you make it a bolt and enclose it.

Makes sense, right?  

[Fresnel]

ArmasTermin

Weight must be one issue, scopes being another. Mounted optics on rifles are closer to the face than they are on pistols. You don't want a slide on a rifle pegging you in the cheek. So you make it a bolt and enclose it.

Makes sense, right?

It makes sense as to why they DON'T do it on rifles, but it doesn't explain why they DO do it on pistols.  

[ArmasTermin]

Fresnel

ArmasTermin

Weight must be one issue, scopes being another. Mounted optics on rifles are closer to the face than they are on pistols. You don't want a slide on a rifle pegging you in the cheek. So you make it a bolt and enclose it.

Makes sense, right?

It makes sense as to why they DON'T do it on rifles, but it doesn't explain why they DO do it on pistols.

Because it would take more space and be more cumbersome. I would think.  

[Fresnel]

ArmasTermin

Fresnel

ArmasTermin

Weight must be one issue, scopes being another. Mounted optics on rifles are closer to the face than they are on pistols. You don't want a slide on a rifle pegging you in the cheek. So you make it a bolt and enclose it.

Makes sense, right?

It makes sense as to why they DON'T do it on rifles, but it doesn't explain why they DO do it on pistols.

Because it would take more space and be more cumbersome. I would think.

From what I can see in my head, the pistol would need to be a tad taller to accomodate the gas tube and perhaps a bit longer in the back so the bolt can move and to fit the spring (if it's designed that way, which it may not be), but because there's no slide to bite that's not too much of an issue. Actually, on second thought, it might not need to be taller. Move the barrel down to where the traditional recoil spring would be and put the gas tube on top... With less recoil force coming from the lower firing chamber and lighter moving parts, it might even be more accurate and easier to handle.  

[ArmasTermin]

Fresnel

ArmasTermin

Fresnel

ArmasTermin

Weight must be one issue, scopes being another. Mounted optics on rifles are closer to the face than they are on pistols. You don't want a slide on a rifle pegging you in the cheek. So you make it a bolt and enclose it.

Makes sense, right?

It makes sense as to why they DON'T do it on rifles, but it doesn't explain why they DO do it on pistols.

Because it would take more space and be more cumbersome. I would think.

From what I can see in my head, the pistol would need to be a tad taller to accomodate the gas tube and perhaps a bit longer in the back so the bolt can move and to fit the spring (if it's designed that way, which it may not be), but because there's no slide to bite that's not too much of an issue. Actually, on second thought, it might not need to be taller. Move the barrel down to where the traditional recoil spring would be and put the gas tube on top... With less recoil force coming from the lower firing chamber and lighter moving parts, it might even be more accurate and easier to handle.

Try to draw out a design. Thinking like that is why the lead ball musket is now the M16.

Seriously, put some good thought in this and you might really get something.  

[Fresnel]

ArmasTermin

Fresnel

ArmasTermin

Fresnel

ArmasTermin

Weight must be one issue, scopes being another. Mounted optics on rifles are closer to the face than they are on pistols. You don't want a slide on a rifle pegging you in the cheek. So you make it a bolt and enclose it.

Makes sense, right?

It makes sense as to why they DON'T do it on rifles, but it doesn't explain why they DO do it on pistols.

Because it would take more space and be more cumbersome. I would think.

From what I can see in my head, the pistol would need to be a tad taller to accomodate the gas tube and perhaps a bit longer in the back so the bolt can move and to fit the spring (if it's designed that way, which it may not be), but because there's no slide to bite that's not too much of an issue. Actually, on second thought, it might not need to be taller. Move the barrel down to where the traditional recoil spring would be and put the gas tube on top... With less recoil force coming from the lower firing chamber and lighter moving parts, it might even be more accurate and easier to handle.

Try to draw out a design. Thinking like that is why the lead ball musket is now the M16.

Seriously, put some good thought in this and you might really get something.

If only I had CAD. I should have been a MechE. But no, all I have is circuit design CAD...

Goddamn EE.  

[OberFeldwebel]

Fresnel

ArmasTermin

Fresnel

ArmasTermin

Fresnel

ArmasTermin

Weight must be one issue, scopes being another. Mounted optics on rifles are closer to the face than they are on pistols. You don't want a slide on a rifle pegging you in the cheek. So you make it a bolt and enclose it.

Makes sense, right?

It makes sense as to why they DON'T do it on rifles, but it doesn't explain why they DO do it on pistols.

Because it would take more space and be more cumbersome. I would think.

From what I can see in my head, the pistol would need to be a tad taller to accomodate the gas tube and perhaps a bit longer in the back so the bolt can move and to fit the spring (if it's designed that way, which it may not be), but because there's no slide to bite that's not too much of an issue. Actually, on second thought, it might not need to be taller. Move the barrel down to where the traditional recoil spring would be and put the gas tube on top... With less recoil force coming from the lower firing chamber and lighter moving parts, it might even be more accurate and easier to handle.

Try to draw out a design. Thinking like that is why the lead ball musket is now the M16.

Seriously, put some good thought in this and you might really get something.

If only I had CAD. I should have been a MechE. But no, all I have is circuit design CAD...

Goddamn EE.

You can always pirate a copy of CAD.
I did that for my CAD class in highschool so that I could work on my assignments at home.  

[Fresnel]

OberFeldwebel

Fresnel

ArmasTermin

Fresnel

ArmasTermin

Because it would take more space and be more cumbersome. I would think.

From what I can see in my head, the pistol would need to be a tad taller to accomodate the gas tube and perhaps a bit longer in the back so the bolt can move and to fit the spring (if it's designed that way, which it may not be), but because there's no slide to bite that's not too much of an issue. Actually, on second thought, it might not need to be taller. Move the barrel down to where the traditional recoil spring would be and put the gas tube on top... With less recoil force coming from the lower firing chamber and lighter moving parts, it might even be more accurate and easier to handle.

Try to draw out a design. Thinking like that is why the lead ball musket is now the M16.

Seriously, put some good thought in this and you might really get something.

If only I had CAD. I should have been a MechE. But no, all I have is circuit design CAD...

Goddamn EE.

You can always pirate a copy of CAD.
I did that for my CAD class in highschool so that I could work on my assignments at home.

Then I run into the two distinct problems of "I have a mac" and "I don't know how to use CAD".

Whoa, really weird idea here. With a gas system, it would be possible to make the barrel itself the moving part. The barrel slides forward out of the gun to eject and chamber each round. It sounds like a bad idea, but I can't give a reason as to why. I think it'd require rimmed rounds though, so maybe .22 only.

EDIT: Ooh, HighDesign, which is apparently very good, has a free trial version. biggrin  

[OberFeldwebel]

Fresnel

OberFeldwebel

Fresnel

ArmasTermin

Fresnel

ArmasTermin

Because it would take more space and be more cumbersome. I would think.

From what I can see in my head, the pistol would need to be a tad taller to accomodate the gas tube and perhaps a bit longer in the back so the bolt can move and to fit the spring (if it's designed that way, which it may not be), but because there's no slide to bite that's not too much of an issue. Actually, on second thought, it might not need to be taller. Move the barrel down to where the traditional recoil spring would be and put the gas tube on top... With less recoil force coming from the lower firing chamber and lighter moving parts, it might even be more accurate and easier to handle.

Try to draw out a design. Thinking like that is why the lead ball musket is now the M16.

Seriously, put some good thought in this and you might really get something.

If only I had CAD. I should have been a MechE. But no, all I have is circuit design CAD...

Goddamn EE.

You can always pirate a copy of CAD.
I did that for my CAD class in highschool so that I could work on my assignments at home.

Then I run into the two distinct problems of "I have a mac" and "I don't know how to use CAD".

Whoa, really weird idea here. With a gas system, it would be possible to make the barrel itself the moving part. The barrel slides forward out of the gun to eject and chamber each round. It sounds like a bad idea, but I can't give a reason as to why. I think it'd require rimmed rounds though, so maybe .22 only.

EDIT: Ooh, HighDesign, which is apparently very good, has a free trial version. biggrin

Or you could go into business and make your own rimmed calibers.
9x19R?  

[Fresnel]

OberFeldwebel

Fresnel

OberFeldwebel

Fresnel

ArmasTermin

Try to draw out a design. Thinking like that is why the lead ball musket is now the M16.

Seriously, put some good thought in this and you might really get something.

If only I had CAD. I should have been a MechE. But no, all I have is circuit design CAD...

Goddamn EE.

You can always pirate a copy of CAD.
I did that for my CAD class in highschool so that I could work on my assignments at home.

Then I run into the two distinct problems of "I have a mac" and "I don't know how to use CAD".

Whoa, really weird idea here. With a gas system, it would be possible to make the barrel itself the moving part. The barrel slides forward out of the gun to eject and chamber each round. It sounds like a bad idea, but I can't give a reason as to why. I think it'd require rimmed rounds though, so maybe .22 only.

EDIT: Ooh, HighDesign, which is apparently very good, has a free trial version. biggrin

Or you could go into business and make your own rimmed calibers.
9x19R?

Yeah, I just got to thinking about that again today and slapped myself. If the barrel moves, so does your point of aim. stressed  

[Stoic Socialist]

[/thread]