question about rifle barrels

Are you talking about older bolt action rifles or newer ones.

WWII issue

I don't know for certain, but i would guess for the bayonet. If i remember right most bayonets had a loop at the base of the blade that went over the muzzel.But it would make sense to have something at the base of the handle to help lock it in place. But that is only a guess.

That is where the gas operated piston is located for semi auto weapons. 

If its for semi auto rifles, why doesnt the carbine have one?

The first pic is a shotgun & the tube is the magazine.

2nd is a rifle with tube magazine.

3rd is a gas tube.

4th I believe is a bayonet mount.

These "bits" are either bayonet mounts, gas tube, magazine or cleaning rods (on older rifles).

So, on a rifle that does not have a bayonette and uses a magazine, instead of holding single rounds inside the gun (like a shotgun or m1) would that need one of those?

On automatics that is a gas tube to take gun gasses back to cycle the action. On bolt guns sometimes there is a cleaning rod stored there.

On lever action rifles and almost all shotguns it is a tube magazine.

A very general answer, but that should get the point across.

The definitive example of a gas tube on a semi or fully automatic assault gun is the AK-47 The tube is above the barrel a short way from the muzzle. Pressurized gas from the shot fired cocks the bolt back for the next round. All guns of this design the first round must be manually set in firing position by pulling the bolt back.

The M-16 is a sleeker design yet still is of the same basic design principal. Due to combustion gas being used to *** the bolt fouling can occur after repeated use or poor grade propellant in the cartridges used. Hence the need to field strip & clean this weapon for reliability.

HK took the M-16 design further by adding a chamber with a rod coming back to load the next round. This eliminated any combustion gas fouling the bolt and helped dissipate heat. The HK 416 is now recognized as the most reliable assault rifle available  as special forces around the world now choose this design over all others. 

* Regarding tube magazines*

There is a certain nostalgia due to the popularity of 'Cowboy shooting' and yes lever action rifles of the late 1800's all featured this loading innovation. If ballistics & accuracy are important avoid tube fed guns. By design the bullets are pushing on each other tail to tip, not conclusive to keeping your match grade ammunition defect free. 

Not all lever action guns have tube feeds. I own a Browning lever action 30-06 which is clip fed. The open hammer by design is the safest action possible as there is no mistaking if the gun is in firing position or not, also it can be manually set to neutral position by holding with your thumb and pulling the trigger, then easing the hammer down to safe.

STV Is there a certtain rifle or type you are wanting to know about

Im just curious in general.  I am curious about the M1 Carbine, Since it does not have one is the tube within the stock?

I am curious about that and lever action rifles, if there clip fed do they need it?

smeagol the vile

So, on a rifle that does not have a bayonette and uses a magazine, instead of holding single rounds inside the gun (like a shotgun or m1) would that need one of those?

Smeag,

Not entirely clear on your question here, but I think the answer it is yes.  Many rifles and shotguns have a tubular magazine under the barrel.  A weapon that does not have a tubular magazine like that, but is gas operated, is likely to have a similar (though probably smaller) tube.  Consider the M16 family of weapons - the gas tube on that is about the diameter of a straw. 

Also to answer an earlier question, I believe the carbine does 'have one', it is just enclosed in the wooden stock (the carbine is gas operated).

AHHH! now that makes sense.

So even if there not visible they are there, ok that helps me alot.

The M-1 carbine uses a short stroke gas piston designed by a guy known as "Carbine" Williams.  He was a prisoner in a state prison at the time when he came up with the design.  Winchester used it when designing the carbine.  Jimmy Stewart played "Carbine" Williams in a movie about his life.  Use Wikipedia to find out more about these types of weapns and action types.

If the weapon is semi auto or full auto and gas operated, it will have some sort of gas tube. Some are also recoil or blowback operated. In those cases it has no gas tube or gas port/piston. Tommy guns,  HK's MP-5/G-3 series, and the Browning M2 .50, as well as most semi auto pistols fall under these catagories. Usually those operate  that when fired the pressure in the firing chamber reaches a point where it will force the bolt back to extract the spent casing and cycle the action of the weapon.

Older combat rifles (approx> WW2) tend to be bolt action & if there is a additional "tube" near the barrel, it would be for attaching bayonets & accessories, or on some older rifles it may be a rod.

By the time personal automatic rifles came about, the need for bayonets was not seen as so important & the fittings for them became less of an integral part of the weapon, bayonets became smaller & such obvious fitting for them disappeared.

Automatic weapons are generally gas or blowback operated. Blowback weapons drive their cycle by recoil, so no gas tubes are required - although this does appear on some rifles it is generally found on smaller automatic weapons like the MP-40 or MP5. Most modern automatic rifles are gas operated, using combustion gas from the round to power the mechanism. Exactly how obvious the gas tube is depends on a number of factors - the round in use, the length of the barely, the length of the stock....... Gas tubes can be found above or below the barrel & in some weapons, like the SLR are shrouded by the stock.

Shotguns with a magazine capacity generally have a tubular magazine below the barrel, which is operated by a pump action handle sliding on the magazine.

Franchi SPAS 12 shotgun, with 8 round magazine & pump action;

Browning Automatic Rifle, with gas tube below barrel;

M1 Garand, with below barrel gas tube;

Ruger Mini 14, with below barrel gas tube enclosed is stock;

FN FAL / SLR, with above barrel gas tube, again enclosed;

AK-47, with obvious above barrel gas tube;

M-16, with above barrel gas tube which is visible below the foresight;

A diagram of the M-16, showing the gas tube;

Thank you very much everyone.  That answers every question I had.  I greatly appreciate it.

Let me get your opinion then guys, does this look good to you?

smeagol the vile

Let me get your opinion then guys, does this look good to you? 

 

I guess it depends on what it is supposed to be.  Is it some form of sawed of shotgun, with a dropdown magazine?  Or is it a rifle?  If it is a rifle, the stock looks a little wierd, but depending on what you intend to use it for, I think it looks fine.  But remember, context is everything.

One other point - I suspect you'll do it anyways, but you need to file down the end of the barrel.  When you cut the copper wire, you left the ends pinched.

yea, I tried to create a rifle of my own design.  It is meant to be a lever action rifle for a project I am working on.  and I will file down the copper

May as well as here instead of making a new thread

Bipods on automatic rifles and Machine guns, do they hang free or do they Lock into position.  What I mean is when you were running with a gun where a bipod was attached would it swing under the rifle or would it be put up against the rifle and locked or something?

Most have spring locks that act in the open or closed position, others have  mechanical locks.

smeagol the vile

May as well as here instead of making a new thread

 What I mean is when you were running with a gun where a bipod was attached would it swing under the rifle or would it be put up against the rifle and locked or something?

The short answer is Yes.

As was already pointed out, most weapons with bipods have some mechanism that allows the bipod legs to be folded under the weapon and locked in place.  However, you'll see plenty of pictures of guys running with the bipods swinging free.  Maybe they didn't take the time to lock them in place when the moved from their last firing position.  Maybe they jostled the weapon enough for them to shake free.  Could be a lot of reasons, but the result is your kinda free to do whatever you think looks best for your project.

And every now and then you run into a bipod type that does not fold flush with the barrel or stock and instead just clips on to the weapon alligator clip style. A GI bipod for the M-16 of this type was developed. Also most of the attached bipods have some side to side play to allow for uneven angled terrain.

Thanks alot guys that helps alot

I have decided not to use the rifle I scratched for this project.  Im not unhappy with it, but comparing it to the rifles that come with kits its like two times bigger then it should be.

How the heck do they detail those little things, or are the molds produced by a machine?