Old Small Arms Revived...... With Some Tweaks

[Maverick]

Dy, the first pic illustrates the workings of the gas system for these weapons.  Please note, it's an abbreviated system with a fairly large chunk of the barrel & gas port taken away for viewing ease.  The basic line is the gas of the weapon's firing directly hits the breechblock reloading the weapon, unlike the SLR/FAL and most other types which have a piston that is pushed by the gas into the block.  The second pic of the heavy-barrelled FAL shows the gas tube above the barrel that contains the gas piston.

The gas block is an integral part of the weapon one way or the other, whether there is a front sight or not.  You'll see pics of 'Flat Top' M16/AR-15 variants with the block still in place, albeit without the sight.  The 3rd pic of the 'flat top' M4 illustrates this.

HTH,

Mav

[dy031101]

So basically...... can I assume that a barrel with gas block attached to it but without much contact with other gun parts (except of course for the gun's receiver) is still free-floating even for gas piston versions of the M16/M4?

[Wyrmshadow]

or you can always devolve technoligicly. Recently found this POS.


With AK's as cheap as they are, you really need to be somewhere in the boonies to be forced to make this.

[rickshaw]

What exactly does the gas block do?  I know in many cases it also serves as a front sight base, but since I'm not well-knowledge on the inner workings of a gun, what does it do otherwise?

Would its being attached to the barrel or not be factored into whether the barrel is free-floating or not?  Or is the gas block supposed to be attached to the barrel regardless?

Thanks in advance.

In the M16 series, what is called the "gas port" or "gas regulator" (although strictly speaking that is a separate part of the weapon) in most other weapons is called the "gas block".  Basically it is where gas from the barrel is bled off to the gas cylinder to push the gas piston to the rear so that it turn can strike or move the bolt carrier so that it will then unlock the chamber and eject the spent case and then reload the weapon.   In the M16 and other weapons which utilise the Llungman gas system, the gas piston is severely abbreviated and is directly attached to the bolt carrier.  Most other assault or semi-automatic rifles utilise a separate piston (sometimes they are longer, some are "short-stroke" short pistons).  Those systems tend to be more reliable than the Llungman one.  Partly its to do with the physics, mainly its to do with fouling - the Llungman system is notorious for its fouling and that invariably leads to stoppages.

[rickshaw]

So basically...... can I assume that a barrel with gas block attached to it but without much contact with other gun parts (except of course for the gun's receiver) is still free-floating even for gas piston versions of the M16/M4?

No.  Now, if you were suggesting that of the gas piston, then you'd be correct but as the M16/M4 does not strictly speaking have a gas piston as such, then you'd be wrong.   The gas chamber (the tube in which the gas piston works) is firmly affixed to the receiver and barrel of the weapon.

[dy031101]

Okay, to sum up my understanding from previous responses, in direct impingement gas M16/M4, the gas block is attached to the barrel regardless, so when one says "free-floating the barrel", he/she really means the barrel and its attached gas block, correct?

Now, if you were suggesting that of the gas piston, then you'd be correct but as the M16/M4 does not strictly speaking have a gas piston as such, then you'd be wrong.

When I said "gas piston version", I'm trying to invoke examples such as HK's 416 or Sturm, Ruger's SR-556.  Is it still the same case as the original M16/M4?  Or does it need alternative measures to make a marksman's weapon out of those guns (like the private gun ownership question in another forum area, this question is to a certain level inspired by what I've heard of the SEAL Recon Rifle......)?

[Maverick]

Dy,

You're quite correct about the HK416 having a gas piston.  It was one of HK's major improvments over the M4 carbine.

Accrording to HK's literature, the barrel of the 416 is defined as free-floating.  That is, the barrel is attached to the receiver & gas system but doesn't have any other furniture attached directly to the barrel allowing its natural harmonics to be undisturbed.

As for the 'Recon Rifle', it's a fairly amorphous beast from all accounts.  Although the Navy's Crane division designed it, there have been many variations on the baseline weapon.

Turning an issue longarm into a marksman's weapon is a sticky issue IMO.  Some merely add a longer barrel & new optics but still have things like folding stocks.  I know the modern design of various folding stocks are solid, but that's just another thing that can affect the feel of the weapon.  The basic idea is to have an organic sniper-like capability within a line infantry unit as a support weapon.  At the least the weapon should have a heavier barrel, enhanced optics and a fixed stock (this configuration would allow the DM soldier to use the same ammo as his squad), although ramping up the calibre of the weapon wouldn't hurt either, allowing for longer ranged, accurate engagements.

Regards,

Mav

[rickshaw]

Okay, to sum up my understanding from previous responses, in direct impingement gas M16/M4, the gas block is attached to the barrel regardless, so when one says "free-floating the barrel", he/she really means the barrel and its attached gas block, correct?

Strictly speaking the term "free floating" when referring to a barrel means that the barrel is attached only at one point - the front of the metal receiver.   If it is attached at any other point, such as to a gas system, then it isn't "free floating".  Of course, this means that you really can't have a semi-automatic rifle with a "free floating" barrel.  I'm aware that some American manufacturers who attempt to claim otherwise but I rather suspect they don't understand the concept fully.

Now, if you were suggesting that of the gas piston, then you'd be correct but as the M16/M4 does not strictly speaking have a gas piston as such, then you'd be wrong.

When I said "gas piston version", I'm trying to invoke examples such as HK's 416 or Sturm, Ruger's SR-556.  Is it still the same case as the original M16/M4?  Or does it need alternative measures to make a marksman's weapon out of those guns (like the private gun ownership question in another forum area, this question is to a certain level inspired by what I've heard of the SEAL Recon Rifle......)?

Maverick has largely covered that.  At the mimimum what you require is:

* A fixed butt
* An accuracised weapon (ie expertly zeroed)
* Nowadays, but not absolutely necessary - an optical sight zeroed to the weapon
* Perhaps an improved trigger mechanism - most trigger mechanisms in service rifles aren't much good as far as accuracy goes.

Optional extras which seem to be favoured by some:

* A bipod
* Adjustable cheek pad
* A larger calibre

Now, you do have to be careful to differentiate between a "marksman" and a "sniper".  Both have different roles and are used differently tactically.  The two terms really aren't interchangeable although some people do so.

[jcf]

or you can always devolve technoligicly. Recently found this POS.


With AK's as cheap as they are, you really need to be somewhere in the boonies to be forced to make this.

... or you could look at it as embodying the original spirit of the thread (rather than the Guns & Ammo which shootin arn is better that t'other form it has taken)... as an old bolt action revived with Ak components. Sometimes devolution is the best evoluion.

[Maverick]

JCF,

I don't know if you've read thru the recent posts in this thread, but the 'Guns & Ammo' type replies which have supposedly been made have been in relation to questions raised by members here.  Some of us have a keen interest in the mechanics & operations of firearms, but that doesn't necessarily make us ill-educated rednecks and funnily enough, Rickshaw & I (who have contributed to many of the recent questions) are both Australians & well educated, rathre the opposite I should think.  Oh, and the thread was "old small arms revived".  Only the most optimistic could suggest that Franken-AK is anything other than a POS.

Regards,

Mav

[dragon]

or you can always devolve technoligicly. Recently found this POS.


With AK's as cheap as they are, you really need to be somewhere in the boonies to be forced to make this.

You could always market it as a "Northern California Legal" AK Rifle.

[dy031101]

Perhaps inspiration for a project of a backyard gunsmith, like designing a scheme of outfitting a venerable bolt action with furnitures of modern firearms?



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I found this pic at China-Defense.com forum.  Home-made guns- I heard suggestion that the rifles might be bolt-action guns, judging from a lack of identifiable gas system, despite having some visual similarity with Type 56 carbine (SKS) and Type 81 rifle at the first glance.

I couldn't help to wonder if salvaged gun receivers could easily have been utilized if available......

[jcf]

JCF,

I don't know if you've read thru the recent posts in this thread, but the 'Guns & Ammo' type replies which have supposedly been made have been in relation to questions raised by members here.  Some of us have a keen interest in the mechanics & operations of firearms, but that doesn't necessarily make us ill-educated rednecks and funnily enough, Rickshaw & I (who have contributed to many of the recent questions) are both Australians & well educated, rathre the opposite I should think.  Oh, and the thread was "old small arms revived".  Only the most optimistic could suggest that Franken-AK is anything other than a POS.

Regards,

Mav

So you think US subscribers to G & A are ill-educated rubes? Fascinating.

[rickshaw]

JCF,

I don't know if you've read thru the recent posts in this thread, but the 'Guns & Ammo' type replies which have supposedly been made have been in relation to questions raised by members here.  Some of us have a keen interest in the mechanics & operations of firearms, but that doesn't necessarily make us ill-educated rednecks and funnily enough, Rickshaw & I (who have contributed to many of the recent questions) are both Australians & well educated, rathre the opposite I should think.  Oh, and the thread was "old small arms revived".  Only the most optimistic could suggest that Franken-AK is anything other than a POS.

Regards,

Mav

So you think US subscribers to G & A are ill-educated rubes? Fascinating.

Some are, some aren't.  I think before Maverick puts his foot further into his mouth, I'll just explain that generally in Australia where gun culture isn't a big factor in our society, the people who tend to purchase such magazines are usually considered a few 'roos short in the top paddock by most people as far as such matters are concerned...

That doesn't mean its actually true.  Problem is while I'm a gun nut, I'm actually anti-gun foolery. Oh, and I've never read an issue of G&A.

Ducks out again...   

[Maverick]

Guys,

My foot is nowhere near my mouth and at no point did I suggest that G&A readers in the US are ill-educated rednecks.  In fact, I would suggest that JCF was the one who made that inference, not me.  After all this is a quote "rather than the Guns & Ammo which shootin arn is better that t'other form it has taken" from him.

Rickshaw is however correct in suggest that the gun-lobby isn't quite the force here as it is in the US.  That being said, members of said gun-lobby don't necessarily follow the norm that JCF suggested.  Plenty of idiots out there who own guns, but also plenty of non gun owners too who would classify as idiots.

Regards,

Mav