Circular Stroke Piston System

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zollen

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There are two key features I would like to point out.

1. Thumb Screw Pressure Adjustor for different barrel length or suppressor setup. The thumb screw simply increase or decrease the internal blow back gas pressure for the appropriate operation.

2. Composite Piston Dish pushes the bolt carrier group for shell extraction and feeds magazine bullet to the chamber. It completes one operation cycle without the need of buffer tube. This feature helps reduce weight and allows the attachment of folding stock.

3. All key Piston + push arms components are made with heat resistance light weight composite materials.

4. Hopefully the reduction of recoil would be able to achieved by the absent of buffer spring
 
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Its completely unworkable.

This is like a beta type Stirling steam engine but without constant pressure on the system...

No real "design" here, I think you are vastly underestimating the complexity of what would have to happen in order to make something like this work.

Êtes-vous un francophone québécois?
 
Sam Cade said:
Its completely unworkable.

This is like a beta type Stirling steam engine but without constant pressure on the system...

No real "design" here, I think you are vastly underestimating the complexity of what would have to happen in order to make something like this work.

Êtes-vous un francophone québécois?
Click to expand...
Would you be specific other which part of the system that failed? I really want to learn.

I am a Canadian, but I am not from Quebec. This is only a draft conceptual diagram, not design.

Are you suggesting I should have used a dual pistons system where each piston regulates one end of the operation?
 
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Are you suggesting I should have used a dual pistons system where each piston regulate one end of the operation?
Click to expand...

No.

I am suggesting that the entire concept is flawed.

Reciprocation,to rotary motion,to reciprocation with nary a spring in sight.

1. Thumb Screw Pressure Adjustor for different barrel length or suppressor setup. The thumb screw simply increase or decrease the internal blow back gas pressure for the appropriate operation.
Click to expand...
This is just a mess. I think you are trying to say that there is an adjustable gas block.

3. All key Piston + push arms components are made with heat resistance light weight composite materials.
Click to expand...
Ok. Do you know how much heat the parts have to endure? Do you know how the structural properties of various "composite" materials change when subjected to the kinds of temperatures that the gas system will generate?

2. Composite Piston Dish pushes the bolt carrier group for shell extraction and feeds magazine bullet to the chamber. It completes one operation cycle without the need of buffer tube. This feature helps reduce weight and allows the attachment of folding stock.
Click to expand...

Here is where the fundamental problem lies. Without any sort of spring in the action everything would have to be wildly overgassed in order to get the thing to cycle, also, Its entirely possible to have a folding stock AND the mainspring in the butt stock. The Para-Fal does it just fine.

4. Hopefully the reduction of recoil would be able to achieved by the absent of buffer spring
Click to expand...

Explain that. Keep in mind that recoil is linear along the bore axis.



So assuming that we are talking about AR type rifles:

The reciprocation of the buffer inside of the receiver extension actually serves to slow down the recoil impulse getting to the shooter.

An in-line DGI system like Stoner designed is about as simple as you can make a self loading firearm short of blow back, open bolt, full auto, advance primer ignition buzz-gun.
 
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I don't want to be negative, and I'm not an engineer anyway, but I do admire your innovative mindset and I think you should keep trying. One of these days someone is going to come up with a true revolution in gun design, why not you?
 
I see the flaws thus....
1) You need a half rotation to extract the fired cartridge
2) You need a half rotation to chamber the next cartridge
... as illustrated, while the fired cartridge is being extracted the rotary piston is rotating the piston dish and feeding arm past the point where they will be usable for to lad the next cartridge.
3) Once the piston dish has rotated..... what do you do with it now that the feed arm is out of position?

Springs have already been mentioned, but that's a minor point if the mechanical linkages are good.
Reciprocal to rotary and back works fine.. steam locomotives use it all the time. (Of course, they have both steam and vacuum to do the work of springs so it's hardly a fair comparison.)



Lastly, I must add that the return spring for a paratrooper model FN FAL is not located in the folding buttstock, instead the mainspring is retained in a recess of a different bolt carrier, one without the usual 'rat tail'.
para_bbc_btm_sm.jpg
 
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Now... if you really want to come up with something both useful and inventive...
Come up with a way to make an easily loaded magazine for a rifle that uses Dardick 'trounds'
The revolving cylinder loads faster than inline and allows cooling as it cycles, but I can't think of any way to easily load trounds in a magazine that doesn't use feedlips.
Tround, note equal-sided elliptical cartridges.
180px-Dardick_tround_pat_2865126_fig4.png


Dardick feeding concept, note- no feedlips as the trounds slip sideways into the next chamber of the revolving cylinder.
dardick_1958.jpg

Actually... I can imagine a way, but it would feed like a P90 PDW and require a rotating piece.... hmmm....
 
Thanks for the inputs. Yes, my concept was inspired by piston internal combustion engine and stream powered locomotion. Let me think about everyone inputs and hopefully I will come up a better concept. I still think the circular concept is possible If I could work out the details. The main problem is durability, too many moving parts and everyone know there are plenty of simpler designs out there.
 
It's not a good idea. I mean, I'm all for you being creative and all, but this idea is not mechanically efficient. You are trying to apply a mechanical device to the wrong application, and are putting little things on it to make it work. The IC engine is the way it is because it takes expanding gases (like a gun) and turns them into shaft power (NOT like a gun.) The only reason the crank is there is to make shaft power. If you don't need any, don't make any.
 
The main problem is durability
Click to expand...

The main problem is that cartridge firearms are a simple, mature technology in which pretty much every reasonable way to stuff a cartridge into and yank it out of a chamber has been tried.

There hasn't been any significant technological advancement in what constitutes state of the art in say, self-loading pistols in 100 years.

Is a Glock (designed ca.1980 or so) significantly better than a 1911 whose design roots go back to 1900?

A Glock is "better" in the sense that it is cheaper to make,tougher and has a longer service life but either tool in good repair will perform the same tasks.
 
if you really want to come up with something both useful and inventive...
Come up with a way to make an easily loaded magazine for a rifle that uses Dardick 'trounds'
Click to expand...

H&R apparently gave this a go.
 

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4thPointOfContact said:
Now... if you really want to come up with something both useful and inventive...
Come up with a way to make an easily loaded magazine for a rifle that uses Dardick 'trounds'
The revolving cylinder loads faster than inline and allows cooling as it cycles, but I can't think of any way to easily load trounds in a magazine that doesn't use feedlips.
Tround, note equal-sided elliptical cartridges.
180px-Dardick_tround_pat_2865126_fig4.png


Dardick feeding concept, note- no feedlips as the trounds slip sideways into the next chamber of the revolving cylinder.
dardick_1958.jpg

Actually... I can imagine a way, but it would feed like a P90 PDW and require a rotating piece.... hmmm....
Click to expand...
So.. you think it is possible to utilize Dardick trounds for replacing the standard AR Reciprocating shell extraction and shell feeding. Thereby eliminating the need of gas tube, gas block, buffer tube, BCG and springs all together.

I am not sure I understand what is the difficulty of loading trounds rounds into a magazine.

Here is what I think it could be done...

Imagine a standard AR magazine that could be loaded elliptical cartridges from the bottom (instead of from the top). A user would hold such a magazine upside down, then open the bottom cover, and just 'pour' elliptical cartridges into a magazine until the magazine is full. Then finally a user would manually rotate the cylinder (which is part of the magazine) to properly load the cartridges in the cylinder's empty chambers.
 
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Sam Cade said:
In short, NO. You still have to power the cylinder turning.


...anyway, the Dardick failed for a reason:
It was inferior to other already extant designs.
Click to expand...
True. It does not change the fact that the conventional design of BCG and buffer tube would be no longer needed. It would still need gas block, gas tube and a new design of a firing pin and springs.
 
This concept would also simplify the parts inter-changeability for different calibers. All we would need are barrel and magazine (which house the cylinder) for the desired caliber. A quick change barrel system like Remington ACR and RGP, would greatly improve this concept modularity.

I don't like the idea of using specialized rounds like trounds rounds, it would be better to utilize the standard 5.56mm cartridge. Another problem is that the magazine would be much heavier and bigger than any conventional AR magazines. It is because this type of magazines would housed the metal cylinder and the ejection port.

Let me think about this....
 
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Here's my attempt on building onto your rotating piston design. The only way I could see something like that working is on a reciprocating platform with a secondary gas piston to actuate lock up. Here's my picture, it might be easier to figure out.
 

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LJ-MosinFreak-Buck said:
Here's my attempt on building onto your rotating piston design. The only way I could see something like that working is on a reciprocating platform with a secondary gas piston to actuate lock up. Here's my picture, it might be easier to figure out.
Click to expand...
I have already considered a dual pistons design where each piston regulates one end of the movement. But it would increase the complexity of the system while I am trying to simplify the concept.
 
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