The Small Arms Thread, Part 8: 2018; ICSR to be replaced by US Army with interim 15mm Revolver Cannon.

[Walter_Sobchak]

Always be sure to be well armed when doing laundry.

 

[Donward]

Just a reminder that grandpa/great-grandpa was a stupid, 19-year old kid at some point in his life too.

[Walter_Sobchak]

Looking at the picture, I have to wonder if BAR gunners got really tired of that magazine digging into their back while having the rifle slung over their shoulder.  The M1 looks quite a bit more comfortable.  

[Donward]

Looking at the picture, I have to wonder if BAR gunners got really tired of that magazine digging into their back while having the rifle slung over their shoulder.  The M1 looks quite a bit more comfortable.  

Not sure.

 

But I do think it is a pretty good rule of thumb in my observation that the biggest dudes in the squad/platoon were told to lug the BAR around as was the case with my late-great-uncle Bud.

[Sturgeon]

I knew a guy who was five foot two who was a BAR gunner. The CO or whomever thought it would be funny, apparently.

[Collimatrix]

Looking at the picture, I have to wonder if BAR gunners got really tired of that magazine digging into their back while having the rifle slung over their shoulder.  The M1 looks quite a bit more comfortable.  

 

Worse than the magazine is the charging handle sticking out of the left side:

 

[Meplat]

Just a reminder that grandpa/great-grandpa was a stupid, 19-year old kid at some point in his life too.

My maternal grandfather was an A&E at 19.  He worked for Packard for a while before enlisting in the USAAC in '37

 

I knew a guy who was five foot two who was a BAR gunner. The CO or whomever thought it would be funny, apparently.

 

The later versions are absurdly tame. A bit heavy, but very manageable.  I bet I could teach most reasonably experienced shooters to handle a M1918 in under a day.   And that is with the old Semi/ ,full ROF versions, not the much gentler A2's.

 

Worse than the magazine is the charging handle sticking out of the left side:

 

 

An older uncle mentioned how they'd use bootlaces to "jungle sling" the BAR.  Basically hung the thing from a shoulder, and ran it like a pure supression weapon, with a second keeping the thing fed with mags.

[EnsignExpendable]

Excerpt from a Soviet examination of an MP-28: "The trigger mechanism of the Schmeisser submachinegun is a good example of now not to design a select fire trigger mechanism"

[LoooSeR]

Nigerian SF. Do i see a lot of Zenit-made parts?

[LoooSeR]

 

Another DIY anti-materiel rifle in use with the Islamic State near Mosul.

[LoooSeR]

Degtyarov plant GPMG

[Zyklon]

MG-74

 

[Oedipus Wreckx-n-Effect]

I'm... I'm speechless. 

 

They've made something, actually made something, more stupid than the 6.8 SPC.

 

[Sturgeon]

MG-74

That guy on the right looks like he came straight out of the new Kojima game.

[roguetechie]

Someone apparently rediscovered salvo squeeze bore ammo but only looked at the pictures...

One of my gun design heros was a big proponent of the SSB concept in the years just before he retired.

Russell S. Robinson was his name.

Speaking of which, I have a decent PDF copy of the two articles covering his work Fighting Firearms did years ago.

If Sturgeon wants, I can email it to him if he wants to put it in his document repository here.

[Sturgeon]

Yeah, please do.

[Khand-e]

I'm... I'm speechless. 

 

They've made something, actually made something, more stupid than the 6.8 SPC.

 

 

I guess they forgot to get the memo that you generally need this thing called "propellant" and actual room for it to cause a firearm cartridge to be functional.

 

I mean, rounds like .22 CB can get away with just the energy of the primer going off, but that has the quality of "being fucking tiny."

[Donward]

I'm not an expert on reloading but there there probably is enough of a powder charge in that .45 Colt round to get those idiotic projectiles down the barrel without one becoming jammed.

 

Also, if it is a child molester, shouldn't the rounds be aimed a bit lower?

[Khand-e]

I'm not an expert on reloading but there there probably is enough of a powder charge in that .45 Colt round to get those idiotic projectiles down the barrel without one becoming jammed.

 

Also, if it is a child molester, shouldn't the rounds be aimed a bit lower?

 

I'm sure enough of one to send them downrange at blinding velocities that would make a chronograph not even detect anything.

[Miroslav]

Excerpt from a Soviet examination of an MP-28: "The trigger mechanism of the Schmeisser submachinegun is a good example of now not to design a select fire trigger mechanism"

 

Cool quote! Do you have a source?

[Collimatrix]

I've been looking at the trigger mechanisms in bullpup rifles recently. Since a bullpup's hammer/striker and trigger are not co-located, there has to be some sort of machinery there to transmit the trigger pull to the bit that whacks the primer.

-The British EM-1 and EM-2 bullpup designs used extremely complicated hammer and striker systems, respectively.



The EM-1



The EM-2


EM-1 had a linear hammer which, when released by the sear went flying backwards, hit a lever which then hit the firing pin. EM-2 had a striker housed in the bolt body that also forced the locking flaps outward, somewhat similar to the Degtyaryov machine gun designs.

-The Steyr AUG uses what is now the prototypical bullpup trigger mechanism:



In this design, transfer rods housed in the stock act on a hammer pack housed just behind the magazine well. The regular sear and the disconnector act on the tip of the hammer, at the far end from the axis pin. The auto sear is located near the base of the hammer, where the regular sear is on an AR-15. Unlike an AR-15, the auto sear is always engaged, not just when the rifle is in auto.

Fire selection is done by trigger pull. Pulling the trigger a short distance will push the sear off the tip of the hammer and release it. As the rifle cycles, the hammer will be caught by the disconnector, so the rifle will fire once until the trigger is released or pulled harder. If the trigger is released, the disconnector will slip off the hammer, and the sear will catch the hammer, which prepares it for another shot. If the trigger is pulled further back, the disconnector is also pushed back and out of engagement with the hammer, which means that only the auto sear will be holding the hammer. The auto sear is automatically disengaged by the bolt carrier as it goes into battery, letting the hammer fly.

So a short trigger pull gives semi auto, while a long pull gives full auto. Groovy.

The trigger mechanisms in the FN F2000 and P90 are mechanically clones of the AUG trigger and work in exactly the same way, down to the relative location of parts. The way the safety and selector work on the FN designs is a simple trigger block. "Safe" prevents the trigger from moving at all. "Semi" allows the trigger to move, but only far enough to disengage the regular sear. "Auto" allows the trigger to move far enough to disengage both the regular sear and the disconnector. The AUG only has a safety, and lacks the mode selector, requiring a precise touch on the trigger (although a selector could easily be retrofitted).

Also of note is that the parts of the fire control group on all three designs are made mostly of plastic.

In all three designs the manual safety functions by locking the trigger, but there is also an additional inertial drop safety in all three designs to remedy the inadequacy of a simple trigger blocking safety.

-The FAMAS accomplishes basically the same thing as the AUG, but the parts are somewhat different and in different places. This statement applies to the FAMAS generally.



Just like the AUG, fire mode selection is achieved by the length of the trigger pull. Just like the F2000 or P90, there is a safety/selector that acts by simply restricting the length of the trigger pull. Interestingly, the FAMAS appears to use the auto sear as the disconnector. An optional burst limiter has been added to the rear of the hammer pack. There is a switch on the underside of the stock of the rifle that engages or disengages this burst limiter. If the forward safety is in the full auto setting and the burst limiter is engaged, a long trigger pull will fire the rifle in three round burst. If the limiter is disengaged, the rifle will fire full auto.

[Meplat]

I'm not an expert on reloading but there there probably is enough of a powder charge in that .45 Colt round to get those idiotic projectiles down the barrel without one becoming jammed.

 

Also, if it is a child molester, shouldn't the rounds be aimed a bit lower?

 

Look at the propellant volume needed when one uses something like Bullseye.  6.5 to 7 grains will drive a 250 grain pill to the low/mid 800 FPS range.

 

The bigger issue is launching those things down the tube while maintaining reasonable pressures as to not blow the topstrap on an antique '73 Colt. 

[Donward]

Look at the propellant volume needed when one uses something like Bullseye.  6.5 to 7 grains will drive a 250 grain pill to the low/mid 800 FPS range.

 

The bigger issue is launching those things down the tube while maintaining reasonable pressures as to not blow the topstrap on an antique '73 Colt. 

 

You'd think that anyone who has the wherewithal to drop $5,000 or $10,000 or more on an antique Peacemaker would have enough common sense not to fire one of those rounds through it.

 

One would think...

 

...

[Meplat]

You'd think that anyone who has the wherewithal to drop $5,000 or $10,000 or more on an antique Peacemaker would have enough common sense not to fire one of those rounds through it.

 

One would think...

 

...

 

Nope.  

 

Loads of people think "if I can chamber it, I can shoot it".

[Donward]

Nope.  

 

Loads of people think "if I can chamber it, I can shoot it".

 

I guess on the plus side, folks like that make surviving specimens of historical firearms all that more collectible...