The Firing Line Forums

Go Back   The Firing Line Forums > Hogan's Alley > Handguns: General Handgun Forum

Closed Thread
 
Thread Tools Search this Thread
Old April 13, 2018, 06:34 PM   #1
Monday
Member
 
Join Date: September 29, 2016
Posts: 28
Next level harmonica pistol

Hello, i came up with a design of a harmonica pistol, that will basically work like a semiauto. It could be made lika a derringer with the "magazine" in the handle, a very compact pistol.

Here's how it work

The magazine:
https://imgur.com/a/veR37

The barrel:
https://imgur.com/a/luWTk
(The block at the rear got slots to fit the magazine, so it's not solid steel, the next pictures will show this better)

Operation:
https://imgur.com/a/KcFuC

Barrel and magazine in 3D:
https://imgur.com/a/poEDn


The whole idea with the design, is that the bullet blocks the magazine, and when the bullet is fired the magazine can chamber the next round.

What do you think? Will it work? Give me your thoughts!
Monday is offline  
Old April 13, 2018, 06:49 PM   #2
Cheapshooter
Senior Member
 
Join Date: December 2, 2007
Location: Missouri
Posts: 7,552
So as I understand your design, the magazine is the chamber. But with the space you need for the bullet to clear the lower part of the barrel you will in reality only have half of a chamber. The expanding gas will escape through the wide gap that allows the magazine, and next round to move up. The fired bullet will have such little "chamber" pressure that it most likely won't even clear the muzzle.
Of course a bullet stuck in the bore of your design won't cause any problems when the next round is fired because all the gas pressure will be escaping out the magazine like the round before.
__________________
Cheapshooter's rules of gun ownership #1: NEVER SELL OR TRADE ANYTHING!
Cheapshooter is offline  
Old April 13, 2018, 06:55 PM   #3
Monday
Member
 
Join Date: September 29, 2016
Posts: 28
The gasses escaping through the slots is one of my concerns to, but the slot will only be like 1mm wide, and there will be a bullet at the next chamber that will stop it from leaking out, the only way the gasses can leak out would be through the slot and the chamber above, since there will be no bullet left there.

Will this design work? Will it cause any problems?

Last edited by Monday; April 13, 2018 at 07:03 PM.
Monday is offline  
Old April 13, 2018, 07:11 PM   #4
Cheapshooter
Senior Member
 
Join Date: December 2, 2007
Location: Missouri
Posts: 7,552
It's not the slots. It's the gape the width of the bullet and the length of the exposed bullet that is needed for it to move into position. The "chambers" in the magazine hold the case, but the bullet is basically hanging out in nowhere.
You would need something to also move the cartridge forward so the bullet is in the barrel.
In a revolver the entire cartridge in contained in the chambers of the cylinder. The gap between the front of the cylinder, and the barrel (cylinder gap) is measured in the thousandths of an inch. Foe instance, S&W cylinder gap specs are .005-.010 (five to 10 thousandths of an inch).
Soyou are planning for the bullets of the previous rounds to seal the chamber. Which the pressure now forcing the bullet of the fired round forward, and the exposed portion of the next bullet downward. To seal the gas tight enough the magazine would have to have such tight fit it most likely won't move. Plus, unlike ss you are using square bullets, the tiny portion of the radius of the bullet touching what ever it is trying to seal will still leak a lot of pressure
__________________
Cheapshooter's rules of gun ownership #1: NEVER SELL OR TRADE ANYTHING!

Last edited by Cheapshooter; April 13, 2018 at 07:19 PM.
Cheapshooter is offline  
Old April 13, 2018, 07:51 PM   #5
sgms
Senior Member
 
Join Date: May 30, 2010
Location: Arizona or Ohio depending
Posts: 1,020
How would you sight this pistol? Wouldn't the harmonica coming up as each round is fired with a conventional sight cause the sight be unusable after the first round?
sgms is offline  
Old April 13, 2018, 08:16 PM   #6
Cheapshooter
Senior Member
 
Join Date: December 2, 2007
Location: Missouri
Posts: 7,552
OK, with a few more looks I now see a very lightly shaded area behind the bullet. So this is a cutaway view of that section of the mag. Basically a cylinder flattened out with a slot cut in it. S the slot will still vent gas. Both up towards the empty space, and down onto the next bullet. With tghe slot 1MM wide as you mentioned, it would be four times tge maximum spec for the cylinder gap of a S&W revolver. What is going to push the magazine up? As sgms mentioned how is the "spent" portion of the magazine not interfere with the sights?
__________________
Cheapshooter's rules of gun ownership #1: NEVER SELL OR TRADE ANYTHING!
Cheapshooter is offline  
Old April 13, 2018, 08:55 PM   #7
Bill DeShivs
Senior Member
 
Join Date: April 7, 2006
Posts: 9,700
The question is "Why?"
You definitely are thinking outside the box- maybe in a sack?
__________________
Bill DeShivs, Master Cutler
www.billdeshivs.com
Bill DeShivs is offline  
Old April 13, 2018, 09:03 PM   #8
kozak6
Senior Member
 
Join Date: June 16, 2005
Location: AZ
Posts: 2,981
Yeah, it would vent too much gas.

I'd also wonder if the expanding gases would cause issues with the next round down in the magazine. Or maybe even cause a chainfire!
kozak6 is offline  
Old April 13, 2018, 10:19 PM   #9
reddog81
Senior Member
 
Join Date: October 16, 2014
Location: Iowa
Posts: 1,063
Some .22lr bullets are pretty loose in their case. Is the barrel resting on the bullet? If so it could yank the bullet right out of the case.

It looks like the barrel drops to the next round as each is fired. If so does the firing pin also drop down to each new round?

The open space between each bullet will allow for possible chain fires.

I imagine barrel start to drop before the bullet even leaves the bore. This would cause numerous problems.
reddog81 is offline  
Old April 13, 2018, 11:11 PM   #10
Cheapshooter
Senior Member
 
Join Date: December 2, 2007
Location: Missouri
Posts: 7,552
Quote:
It looks like the barrel drops to the next round as each is fired. If so does the firing pin also drop down to each new round?
The OP mentions in the operation diagram that when the bullet aligned with the barrel leaves the case it allows the magazine to move up.
But what force is used to push the magazine up.
__________________
Cheapshooter's rules of gun ownership #1: NEVER SELL OR TRADE ANYTHING!
Cheapshooter is offline  
Old April 14, 2018, 11:40 AM   #11
Bob Wright
Senior Member
 
Join Date: July 10, 2012
Location: Memphis, Tennessee
Posts: 2,794
Extraction of empty cases seems to be a problem.

What about different bullet shapes or profiles?

As has been pointed out, gas leakage would be a problem, likely lead to severe erosion.


Bob Wright
__________________
Time spent at the reloading bench is an investment in contentment.
Bob Wright is offline  
Old April 14, 2018, 02:39 PM   #12
JohnKSa
Staff
 
Join Date: February 12, 2001
Location: DFW Area
Posts: 21,828
Quote:
It's the gap the width of the bullet and the length of the exposed bullet that is needed for it to move into position.
The gap is only the width of the "tooth" that engages the bullet of the round under the hammer and prevents the "magazine" from moving upwards.
Quote:
You would need something to also move the cartridge forward so the bullet is in the barrel.
In this design, the chambers are in the "magazine" and each chamber completely supports the case. The bullet is fully supported with the exception of the tooth-sized slot above (filled by the tooth when that round is under the hammer) and below the bullet (which is empty).

I agree that gas leaking into the next "chamber" is going to be a problem--I just don't know how much of a problem.
Quote:
But what force is used to push the magazine up.
The pictures don't show that. Because of the tooth, it would have to be loaded in from the bottom of the gun and there would have to be some sort of spring pushing it upwards. Maybe something like the tubular magazines that load by removing the spring/follower, inserting the rounds, and then replacing the spring/follower.
Quote:
Extraction of empty cases seems to be a problem.
If I understand correctly, the cases remain in the magazine and are extracted manually when all the rounds in the magazine have been fired and the magazine automatically ejects out the top of the gun.
Quote:
What do you think? Will it work?
I think you might be able to get it to work.

But I think that a mechanism that advances the magazine when the hammer is cocked is probably going to be simpler and much less problematic in the long run.
__________________
Do you know about the TEXAS State Rifle Association?
JohnKSa is offline  
Old April 14, 2018, 03:28 PM   #13
Cheapshooter
Senior Member
 
Join Date: December 2, 2007
Location: Missouri
Posts: 7,552
JohnKSa, your explanations are quite uderstandable. But the question of the raising magazine obstructing the sights is still an issue.
__________________
Cheapshooter's rules of gun ownership #1: NEVER SELL OR TRADE ANYTHING!
Cheapshooter is offline  
Old April 14, 2018, 03:54 PM   #14
JohnKSa
Staff
 
Join Date: February 12, 2001
Location: DFW Area
Posts: 21,828
To be fair, I'm not sure if some of my explanations are workable--I'm just trying to think about how some of the problems might be solved.

I can't see a good way around the sights problem. The magazine could feed side-to-side, but that would make it a lot wider and pretty much a non-starter for any kind of a practical handgun design. The only three options I see are:

Have offset sights. The sights would be extended out to one side of the pistol so that the magazine doesn't obscure them. Along the lines of the Bren light machine gun.

Put the sights on the side of the gun so that the shooting position would have the gun and magazine held in a horizontal position instead of upright. Sort of like the photoshopped gag pictures of the Glock pistol with sights on the side of the slide instead of on the top.

Don't put sights on the gun at all.
__________________
Do you know about the TEXAS State Rifle Association?
JohnKSa is offline  
Old April 14, 2018, 04:43 PM   #15
Monday
Member
 
Join Date: September 29, 2016
Posts: 28
The magazine is basically a flat cylinder, or a harmonica shaped magazine containing chambers, so the fired cases is extracted and reloaded when all chambers has been fired.

The sight could be a problem, but the idea with this gun is just a simple and small derringer, able to fire faster than a ordinary single action, so the sight isn't my biggest concern. But my idea wasn't to push the harmonica magazine upwards from the begging.

I thought it would be a great idea to create a design which could make a ordinary derringer, or basically any other single action (or maybe double action shotguns etc.) especially break action designs, speed loaded in a reliable and easy way. Otherwise the spent case has to be extracted and manually reloaded after each shot, which makes the fire rate slow..

The evolution of this gun started like this: https://imgur.com/a/V7lGT
and i thought that a chamber that holds the whole rounds, would be a good idea, and i came up with this: https://m.imgur.com/a/gavoh a harmonica like magazine which holds the chambers, chambers which is manually inserted into the main chamber of the barrel.

To extract the fired chamber and chamber a new into the barrel, you just have to push the harmonica magazine (H. Mag.) backwards so the chamber is realeased from the barrel, then aside so a new chamber can come inline the chamber of the barrel and bore, then just push the next chamber down the barrel and fire the gun. So you operate the magazine, instead of operating each small rounds.

The next evolution was this: https://imgur.com/a/ka0zV a H. Mag. that just has to be slided alongside (or upwards) the barrels cut, without haveing to be pushed back and forward to realease and chamber the magazine into the barrel. This design made it possible to hold the H. Mag. in the grip, since the H. Mag. doesn't have to be manually operated, a spring in the end of the grip would work to operate the magazine.

Grooves/hooks hold the magazine inline when fired, and has to be manually released to chamber the next round, that hooks in place.

I thought it would be nice to just have to operate the hammer/firing pin and trigger, so i made this design: https://imgur.com/a/YccoU (bad & primitive image because it evolved fast to the design below) which was made for a open bolt gun, where the bolt push the cartridge into the chamber, and fires it, and when the bolt is pushed back and the firing pin is cocked, a new round will travel up, ready to be fired.

I thought that it wouldn't be a great idea to rest the whole H.Mag. on a single cartridge, so i came up with this: https://imgur.com/a/o9XNR https://imgur.com/a/GPrHE (the dimensions isn’t correct for .22, just made up basic mathematics)

But at this point i thought that it got to complicated, the barrel has to be customized in a very perfect way, and there could be issues with the bolt hitting the blocking pin below, and the blocking pin won't going in, falling out etc.

I came up with this: https://imgur.com/a/19Z2W (ignore the dimensions)

With this design you have to manually pull the blocking pin out, and with a small pin like that, it could be hard to get a grip of it, for example.

So i came up with the slot/teeth design that this thread is about.

But gas leakage and the magazine operating faster than the gas leaving the chamber and bore, etc. could be big issues. And the barrel and magazine won't be that easy to make either.

Today, i made a new design, based on an old:
https://imgur.com/pg1zPhu
https://imgur.com/84z0Sjt

The chamber that holds the round within the chamber of the magazine, is movable.

It's the newest design, you have to manually push the block (which also chambers the round) fully inside the chamber of the magazine.

I think it will be easy to do and it will be fast to operate, and this design allows you to push the block in, instead of getting a grip of the block to pull it out, like the old design, and you won't have small blocking pins to keep in your hand or pocket, or picking up from the ground
https://imgur.com/a/xcQG5 (The dimensions isn't 100%, the visible chamber that blocks the magazine is to wide i guess, and there is no trigger either, the image shows the basics)

Easy safety: https://imgur.com/a/HtDmN

With this design, you could make some kind of trigger that push the block if it's to small for your finger etc., it could also be made like this: which allows you to push it forward, and it also allows the handle to hold everything in place. It won't be any space that can accidentall move the block within the magazine when stored. The blockage will also block the magazine at bouth the left and right sides of the barrel cut, maybe makeing it more stable.

The whole design that i'm chasing here, with this gun, is something very reliable and easy to operate and handle, which is basically fool proof, in that way that it can't go wrong, just a basic single action gun that can be fired like a semi-auto.

Last edited by Monday; April 14, 2018 at 06:13 PM.
Monday is offline  
Old April 14, 2018, 09:25 PM   #16
Rembrandt
Senior Member
 
Join Date: August 10, 2002
Posts: 2,081
Jonathan Browning (JBM's Father) gave up on the harmonica design for a good reason, it's bulky, awkward, and there are better repeater designs. As I understand your design, if a misfire occurs the entire harmonica has to be removed...never have that problem with a revolving cylinder...just rotate it to the next round. Not sure how you plan to index the harmonica so each chamber lines up perfectly with the barrel. Would think a ratcheting tooth mechanism would be required.
Rembrandt is offline  
Old April 15, 2018, 03:27 AM   #17
Danoobie
Senior Member
 
Join Date: April 27, 2017
Posts: 349
^^^^^^^^^^^^^^^^^^^^^^^^
To extend Rembrandt's post, let's push the cart downhill here, and say,
for sake of argument, you solve all the design issues. What would the practical
advantage of the pistol be? What would make it desirable to have, compared to
say, a FNX, 92FS, or a 1911?
Danoobie is offline  
Old April 15, 2018, 07:48 AM   #18
Monday
Member
 
Join Date: September 29, 2016
Posts: 28
Quote:
Originally Posted by Rembrandt View Post
Jonathan Browning (JBM's Father) gave up on the harmonica design for a good reason, it's bulky, awkward, and there are better repeater designs. As I understand your design, if a misfire occurs the entire harmonica has to be removed...never have that problem with a revolving cylinder...just rotate it to the next round. Not sure how you plan to index the harmonica so each chamber lines up perfectly with the barrel. Would think a ratcheting tooth mechanism would be required.
Quote:
To extend Rembrandt's post, let's push the cart downhill here, and say,
for sake of argument, you solve all the design issues. What would the practical
advantage of the pistol be? What would make it desirable to have, compared to
say, a FNX, 92FS, or a 1911?
If a misfire occurs with the latest design, you can either simply recock the hammer/firing pin and fire again, until the round fire, or just chamber a new round in the same way that you would have done if the round did fire.

In case of a squib load, just use a rod down the barrel, (like the rod used as safety) and feel if there is a bullet stuck in there, if so push the bullet straight back into the harmonicamagazine/chamber of the misfired cartridge, with the force of the rod, and reload a new round.

The idea with a harmonica instead of a cylinder, is to make it hold more rounds than a revolver would do, and that the walls of the magazine also gets supported by the walls of the main barrel, that the magazine is inserted in.

The harmonica can be made thin, and stored in the handle.

The next chamber below the chamber which is ready to be fired and inline the bore, index the harmonica. It will work as a block and keep the magazine in place until you push the block/chamber within the magazine all the way, which releases the block and allows the magazine to push upwards with the force of a spring, and the next chamber below will stop the magazine in the same way, and so on.

So for example, if the walls of the main barrel is 8mm, the walls between the chambers of the harmonica has to be 8mm to, so when a chamber is inline the bore the chamber above and below that chamber can be used to index the harmonica, with a block, like a rod, with a dimension that fits inside of those chambers. So the block rest partly inside the chamber below, which a spring forceing up, and along the barrel itself, keeping it index. And when that block is pulled out, the spring will push up the harmonica, and the next block will hit the barrel and hold everything in place.

So with my latest design for example, it uses movable inserts that holds the round and that fits the holes/chambers of the harmonica magazine, so you first insert the round into the insert (which is like small tubes with inner dimension that fits the round and outer dimension that fits the harmonica chamber), then insert the insert into the harmonica partly, allow it to be pushed in, with the space of 10mm for example.

And with a rim thickness of 1mm, make the tube 1mm shorter than the width of the harmonica, so the rim will be fully inside the harmonica, not exposed 1mm outside.

Very reliable and basic gun is my goal, that doesn’t have any small parts to clean and mechanics to fail, no magazine jam etc.

The only parts this gun need is the barrel, the harmonica + inserts, a hammer/bolt attached to a trigger, and the reciever/body, that holds the barrel, magazine and hammer/bolt inplace, and ofcourse the magazine spring, and a spring to the bolt/hammer, if you don’t use any other force.
Monday is offline  
Old April 15, 2018, 09:16 AM   #19
Rembrandt
Senior Member
 
Join Date: August 10, 2002
Posts: 2,081
This is a "two handed" firearm....unless I'm not understanding it correctly. The mechanical functions that normally advance the next round have been deleted in favor of using the shooters hands for that advancement.

For a crippled or wounded defender who has one good trigger finger, in order to get a second shot off they must figure out how to get the harmonica in position for a fresh round.

If you really want to see the obstacles and beneficial functions of this design, try using something along the lines of Solid Works. That would allow you to essentially build it on screen and cycle it.
Rembrandt is offline  
Old April 15, 2018, 09:38 AM   #20
buck460XVR
Senior Member
 
Join Date: December 28, 2006
Posts: 3,788
While it should work, it wouldn't be very practical. Especially considering all the much better designs out there. Kinda like taking as revolver and straightening out the cylinder into a strip. One could use a mechanical stop similar to those used on revolvers instead of using the bullet itself. Problem is you lose compactness and balance. How does one design a holster for a handgun where it's whole configuration changes with every shot fired. Mags, because they are also the chamber would have to be strong....thus heavy and awkward to change/carry extras. With every shot the center of balance would change as the heavy mag moved upward. while the mag could rest in the grip on the first round, where does it go as it moves up? Kinda like reinventing the wheel back to stone.
buck460XVR is offline  
Old April 15, 2018, 03:31 PM   #21
Danoobie
Senior Member
 
Join Date: April 27, 2017
Posts: 349
No, if a misfire occurs, the bullet hasn't left the cartridge, so the harmonica will be held down
by the bullet. From what you're describing, a misfire or squib would be a disaster.
Furthermore, that "1MM" you are so happy with will work against you, as well as for you.

While I can imagine we all would love to see a working prototype, I doubt it would get much
traction with the purchasing public.
Danoobie is offline  
Old April 15, 2018, 03:53 PM   #22
Cheapshooter
Senior Member
 
Join Date: December 2, 2007
Location: Missouri
Posts: 7,552
Quote:
Very reliable and basic gun is my goal, that doesn’t have any small parts to clean and mechanics to fail, no magazine jam etc.
Sam Colt did it in 1836. Revised designs have followed, and are quite successful today!
The "simplicity" you desire in your design is complicated massively by all the possibilities of what could go wrong. It is a mecca for proving Murphy's law.
__________________
Cheapshooter's rules of gun ownership #1: NEVER SELL OR TRADE ANYTHING!
Cheapshooter is offline  
Old April 16, 2018, 11:01 AM   #23
Bob Wright
Senior Member
 
Join Date: July 10, 2012
Location: Memphis, Tennessee
Posts: 2,794
Maybe I'm missing something here, but in case of a mis-fire, dud primer. The magazine cannot be raised with a bulleted round in the barrel. The magazine would have tobe removed through the bottom of the pistol to clear the jam. No racking the slide as in an auto, or skipping that chamber in a revolver.

Empties still must be manually ejected from the magazine much like a Single Action revolver. A no. 2 yellow pencil for the job?

I still think escaping gas downward through the hooded portion of the barrel might wreck the innards of the pistol. That gas has wrecked thumbs!


O.K. Other than an interesting concept/experiment, what advantage over convention actions of contemporary handguns? Novelty will only sell a few guns, such as the Dardick or Gyrojet.


Bob Wright
__________________
Time spent at the reloading bench is an investment in contentment.
Bob Wright is offline  
Old April 16, 2018, 11:35 AM   #24
Cheapshooter
Senior Member
 
Join Date: December 2, 2007
Location: Missouri
Posts: 7,552
In the search for "simplicity" your progression in post #15 has spun your design out of the universe of "simple and reliable". Cartridges, loaded into individual chambers, loaded into a magazine, loaded into a grip that doesn't hold it in because the magazine full of individual chambers, loaded with individual rounds has to move up, blocking any sights, or barrel alignment.
Now only if the chambers were machined into the magazine, which were curved into a circle, and moved by a mechanical hand when the hammer cocked, and indexed by a pawl into a groove in the circular magazine!
My run on sentences are only exceeded in complexity by your "simple" design.
__________________
Cheapshooter's rules of gun ownership #1: NEVER SELL OR TRADE ANYTHING!
Cheapshooter is offline  
Old April 16, 2018, 08:36 PM   #25
Big Shrek
Senior Member
 
Join Date: August 6, 2009
Location: NorthWest Florida
Posts: 1,301
I think you'd be better off recreating the Chicago Palm Pistol...
__________________
Marlin Specialist
Calico Specialist
A gun should be a tool in the hands of a deadly weapon, not a deadly weapon in the hands of a tool.
Big Shrek is offline  
Closed Thread

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 07:07 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2018 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.10836 seconds with 10 queries