Senior design project


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brodbeckrt
September 4, 2012, 03:21 PM
Hello all. I am new here as a member on THR but I have read quite a bit on this site and I decided to join.
I am a Mechanical Engineering Technology Student in my final year. Another student and I are researching a project we feel could be quite helpful. We are developing, designing and building a one handed shotgun for our senior design project. More of the design is the stock than the gun. We came up with the idea because we feel it would help single arm amputees enjoy shooting more comfortably and more accurately. We also have tossed around the idea of use in tactical situations as well. It would be nice to be able efficiently use a shotgun without even the slightest thought of using you other hand.
My thoughts are using a Mossberg 500 or Remington 870 for the pump version and the Mossberg 935 or Saiga for semi-auto.

It is a requirement to gain input from other gun-owners and especially amputees.

I am asking you all for your input, suggestions, products you have seen like this(the more info on them the better. I want to make sure I am not taking anyone's patent or anything), which shotgun(make/model) do you suggest for semi-auto or pump and why?

We do already have a basic design and features list, but I do not want to put it up yet because I do not want to influence your answers in any way. I am more looking for accessories, features, or other things you have used that you added on, modified, or that came with a gun(i.e. a stock I bought for a mossberg was everything I wanted in a gun stock except the end of the butt stock was really thin and was very uncomfortable to shoot. Also when it folded the shells wouldnt eject properly because the stock folded in front of where the shells came out). Which things did you hate or love about them, and obviously why?

Thank you all for your input.

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Sam1911
September 4, 2012, 03:36 PM
I'd rather think that an autoloader would be a no-brainer choice for this. Still quite a challenge between supporting the weight, loading, and working all the controls, but at least once it's loaded and a target presents itself, it will fire several times without needing to re-set the shooter's position/stance/grip to handle recharging duties.

I'd also assume that this isn't a "PGO" (pistol-grip-only) design but a design with a modified stock that somehow lets the shooter's body help with supporting the weight of the gun?

TurtlePhish
September 4, 2012, 04:08 PM
Welcome to THR! :)

That's a great idea for a senior design project, I'd love to see how it turns out.

Sam's right, an autoloader is definitely going to be MUCH easier to operate one-handed. I can't really even think of a way to pump a shotgun without hands....

For one-handed shooting, balance is key. The weight needs to sit naturally in one hand, seeing as there's no second hand in front for support. Bullpup design?

If you're looking for an existing shotgun to use as a base, I'd go for any common autoloader like a Remington, Browning, Beretta, etc.

AI&P Tactical
September 4, 2012, 04:47 PM
If the person has only one arm, meaning the other is gone from the below the shoulder down, I can't see them being able to use many shotguns in a defense situation and would recommend a handgun. However, if they practiced with it a .410 or 20ga coach gun would be a reasonable choice.

Your project if sucessful could bring so great joy into the lives of people in this situation and let them enjoy the shooting sports. The big problem out these is getting it made. It takes close to $60K to get an injection mold into production and without a large market no one in the industry is going to do it. Speedfeed will not even consider an LE type forend for the 870 20ga, yet there are plenty of them out there and plenty of people who would buy it. Even Remington makes several 20ga Home Defense type models but has no LE forend which would allow full use of a side saddle. The numbers are not big enough for these companies to produce it. There are no dedicated forend lights for the 20ga either, yet, there is a market.

For a project like yours, numbers, cost and all that mess should not even be considered as bringing people into the shooting sports we all love to participate in is an honorable endevor. Good luck with the project.

JohnBT
September 4, 2012, 05:16 PM
I vote for a short autoloader with the trigger on a vertical foregrip set not too far forward of the balance point. To keep the cost down, I suppose the front trigger could be linked to the rear trigger with a clamp-on bar assembly on the left side (for a righthander.)

I'm thinking simple is better, because I've driven enough vehicles with off-the-shelf hand controls (and seen many, many more) to know that sometimes the cheapest solution is good enough. This has been drilled into my head over the years by a series of rehab engineers at the office. I've also been around enough zero-effort steering systems to understand the expense of the initial installation and the cost of the upkeep.

Or maybe I'm just cheap. Nah, I had breakfast this morning with a zero-effort steering user and know the problems complexity can bring to a system.

John

Steve C
September 4, 2012, 11:18 PM
30 years ago I belonged to a Trap Club. We had a member that had lost his right arm, I believe his first name was Bill but his last name escapes me now, that shot regularly in practice, competitions and Fun-n-games (also known as Annie Oakley's. He used a single shot Browning, if I remember correctly and held his own with any of the 2 handed shooters. Usually held the gun between his legs for reloads (2nd photo). This thread got me remembering and I went through my old photographs and found a couple he was in. Scanned in and did a little cropping and resizing using Paint Shop so you can see the shooters including Bill (3rd from the right in the first picture) in line shooting a 2 gun Annie Oakley from the back fence. His handicap never held up the shoots and he certainly didn't need any special accommodation. This does go to show you that despite the loss of a limb a determined person can still have fun doing what they love.

If you can design something that helps adapt shotguns so the one armed shooter can continue to play the games they like and hunt with their shotguns then that' would be a wonderful accomplishment.

http://i1171.photobucket.com/albums/r552/s_o_cikkubs/AnnieOakley1.jpg

http://i1171.photobucket.com/albums/r552/s_o_cikkubs/AnnieOakly2.jpg

Virginian
September 5, 2012, 06:48 AM
Tall order. We designed a LNG unit train to transport LNG from the North Slope to the Gulf Coast. Got an A, and a year later our professor "wrote" a paper on the same material that was published in Mechanical Engineering magazine.
I would tend to autoloaders, but obviously the real amputee disagreed.
Good luck.

brodbeckrt
September 5, 2012, 11:28 AM
Thanks for all of the great replies.

We are actually building an auto-loader and a pump. The main reason for the pump is the fact that a lot of people may already have one or they can be bought for much cheaper. I would agree with the fact of not having to cycle the action between shots which is why we are doing the auto loader.

AI&P Tactical: Thanks input... maybe to help clarify a little bit. As of right now our design will not be for defense situations for amputees. I too would recommend a handgun for a that situation. Our design will be geared more towards the sport/hunting aspect of shooting for amputees.
If all(most) goes close to as planned, we wanted to expand our design to many different platforms other than just shotguns. The options are pretty much unlimited. I know there are some companies that produce other outdoor and hunting equipment for amputees and people with other physical handicaps. We would like to use our ability as engineers to optimize the existing equipment or develop new equipment. I can't imagine a life without being able to hunt/shoot/camp/hike etc.

Looking at local businesses and corporations for a career choice, there isn't much of a choice in terms of anything I am interested in. I am hoping we can turn it into a business.
I am picky when it comes to what I want to spend the next 35+ years doing with my life.
My ideal job would only need to meet a few requirements:
1. Pays the bills + a little extra spending $$
2. I actually care and have interest in what I am working on.
3. I am doing something useful, not just being a zombie button pusher for a corporation.

Sorry about the side track back to the topic...

A few comments on the preliminary design ideas:

We are looking into a bullpup or similar type of design to help redistribute the weight of the gun, making it much easier to control with one hand.

Also we would like to incorporate some recoil reduction, enhancing recovery after each shot(less fatigue making it more comfortable to shoot for a longer period of time)

The gun will "anchor" to some point on the shooters body to help with stabilization.

Lastly this will be a "full size" shotgun handled much like any other long gun. It will not be a pistol like coach gun.

I would like to hear some recommendations on barrel lengths as well. We want this to be as versatile as possible: Deer hunt, turkey hunt, skeet shooting, tactical(more for competitions and/or non-amputees),etc.

Keep the great comments and suggestions coming.

oneounceload
September 5, 2012, 11:46 AM
You might also consider a double barrel shotgun - either SxS or O/U

We used to have a Maine lobsterman snowbird here in FL and shoot at our club - his left arm was gone just above the elbow - he was a heck of a shot with his Ruger O/U, cradling what he could in that left arm - trigger hand controlled the firing and reloading aspects nicely

brodbeckrt
September 5, 2012, 03:43 PM
Double barrel was definitely a consideration and still is for further development after the project/graduation. The advisers turned down the double barrel design due to the lack of difficulty. Then they all openly admitted that they know absolutely know nothing about firearms.

TurtlePhish
September 5, 2012, 04:01 PM
brodbeckrt, I thought of a way you could build a pump to use one-handed.

Keep in mind that this is an idea for recreational use, so it's not exactly "tactical" or "combat-ready".

Say you use an 870 as a base. Set it up as a bullpup- I'm thinking recoil pad just an inch or two off the back of the receiver, adjustable for use by different people. Have a pistol grip mounted on the pump for use one-handed, with a trigger transfer bar running up under the receiver, through the grip, and the trigger located so that it can be pulled like an ordinary trigger from the front pistol grip. This trigger assembly won't move when the slide is racked, simplifying the design, but requiring that there be an opening through the front grip so that the pump can be moved with the trigger assembly remaining in place going through it. The end of the stock will need an attachment mechanism of some sort (velcro or some kind of clip?) that secures it to a shooting jacket, keeping it in place on the shoulder when the slide is racked forward.

After the shotgun is fired, the user just moves their trigger finger out of the trigger guard, racks the slide, and puts their finger back in place on the trigger. Kind of annoying compared to an ordinary pump, but it's not an ordinary pump.

56hawk
September 5, 2012, 04:39 PM
The SPAS 12 has a hook that can be turned to support the rear of the stock under the arm. It's actually quite comfortable.

http://www.thehighroad.org/attachment.php?attachmentid=171134&d=1346877204

http://i1025.photobucket.com/albums/y316/righttobeararms8/Gun%20Pics/SPAS1210.jpg

brodbeckrt
September 6, 2012, 10:41 AM
brodbeckrt, I thought of a way you could build a pump to use one-handed.

Keep in mind that this is an idea for recreational use, so it's not exactly "tactical" or "combat-ready".

Say you use an 870 as a base. Set it up as a bullpup- I'm thinking recoil pad just an inch or two off the back of the receiver, adjustable for use by different people. Have a pistol grip mounted on the pump for use one-handed, with a trigger transfer bar running up under the receiver, through the grip, and the trigger located so that it can be pulled like an ordinary trigger from the front pistol grip. This trigger assembly won't move when the slide is racked, simplifying the design, but requiring that there be an opening through the front grip so that the pump can be moved with the trigger assembly remaining in place going through it. The end of the stock will need an attachment mechanism of some sort (velcro or some kind of clip?) that secures it to a shooting jacket, keeping it in place on the shoulder when the slide is racked forward.

After the shotgun is fired, the user just moves their trigger finger out of the trigger guard, racks the slide, and puts their finger back in place on the trigger. Kind of annoying compared to an ordinary pump, but it's not an ordinary pump.
Thanks for the great idea. We were thinking along the same lines for the pump. A lot of great info on here.

56Hawk I never came across that stock\feature in my searches but it does add an existing alternative to my research. Thanks

TurtlePhish
September 6, 2012, 02:51 PM
Thanks for the great idea. We were thinking along the same lines for the pump. A lot of great info on here.


No problem! :)
Glad to help. Good luck with the project!

desidog
September 6, 2012, 04:46 PM
A friend of mine lost an arm to an IED, above the elbow.

We got him shooting again with a "sawed off" 20 o/u; the barrel cut down to 18.5" and threaded for chokes. the stock stayed to balance out the barrel when holding with one hand. Also, you need to use the stock for a second point of stability.

The hard part, if you could say swinging a shotgun one-handed isn't, was the reload. we solved that by taking the belt hook from my Lyman GPP and affixing it to the side of the fore-stock. That way, after firing, he could point it down, hook the gun onto his belt, break open the action, let go of the gun and have it hanging on his belt (albeit awkwardly), drop two new shells in, swing the butt up, grab the grip, pull up and off the belt, and acquire a target.

Fred Fuller
September 6, 2012, 04:54 PM
Ever see a High Standard Model 10?

http://world.guns.ru/shotgun/usa/high-standard-10a-10b-e.html

I have one (a 10-A), and while it's perfectly shootable with one hand, it seems to me it would be hard to fully manipulate safely in a sporting environment with one hand. They're just so SHORT...

The biggest problem with a bullpup (especially as a defensive shotgun) is loading it - a student in the defensive shotgun class I took yesterday had a KSG, and he was having difficulties running that gun with both hands/arms working just fine.

siglite
September 6, 2012, 04:59 PM
My advice would be a design that lays a pistol grip far forward of the center of balance on the shotgun, with a cup or brace that fits into the shoulder at the rear. Trying to shoot a shotgun one handed like a pistol is going to be nearly devastating to the wrists, thus, a "bullpup-ish" design, where very little of the shotgun is extended forward of the wrist would seem optimal. And an adjustable length of pull, tailored to the shooters's arm length would also seem critical so that the stock reaches the shoulder for recoil absorption.

MCgunner
September 6, 2012, 09:30 PM
Hmm....

http://i259.photobucket.com/albums/hh305/goose150/PICT0221.jpg

brodbeckrt
September 8, 2012, 09:02 AM
Thanks all. Keep the great info/input coming.

brodbeckrt
October 6, 2012, 04:38 PM
All,
We have to give a survey on the project to quantify the importance of each "feature" can you please take our survey at a website we are building for the project.
http://rr-outdoors.com/CustomerSurvey.html

Thanks

56hawk
October 6, 2012, 04:52 PM
Done. Questions were a little vague though.

JAshley73
October 7, 2012, 03:34 PM
As I was reading over this, a bullpup, semi-auto came to mind, but bottom ejecting, with a slightly forward mounted pistol grip, ambidextrous AR-15 style safety, and with a magazine tube that loads from the back of the stock, say, through the butt plate/pad. I know this sounds a little tactical, but I think with a sporting length barrel and wood hardware, it would still look ok.

If one had a magazine tube that loaded from the butt plate, the gun could be lowered barrel down, say resting by means of a "tactical" sling, with the butt plate facing up. The mechanism though, would depend on an AR-15 type charging handle to cycle the bolt , but also stretch a magazine spring to be locked in place in the stretched position.
Said spring could be wrapped around the outside of the magazine tube, and would pull a "shell stop" that grabbed the last loaded shell by it's rim/base, and pulled that shell, and all others before it toward the chamber. I can imagine a slot cut the length of the magazine tube, with the magazine spring pulling what looks like a conventional shell stop in tow. Such shell stop could also be spring loaded (traverse to the magazine tube) much like a conventional shell stop. With the magazine spring locked back, you could load fresh shells past the shell stop, each falling free through the tube until full. But since the shells are pulled through the magazine tube, and held in place by the "one-way-only" shell stop, the charging handle could still be cycled to clear jams without fear of emptying shells. And I imagine there's a way to keep the mag-spring latch from latching unless the tube is empty, so that in the event of a jam, one could rack the charging handle just like on an AR-15 without fear of dropping rounds or locking the mag-spring back.

Once the tube's full, a typical bolt release button could be pressed to release the magazine spring, and thus feed a fresh round into the chamber.

I picture the bolt operating in such a way that when closing, it strips off a round from the tube much like a semi-automatic pistol. So after a reload, the fresh, incoming round could also release the bolt - thus the mag-spring latch release would indirectly, release the bolt and load the first round. After firing, the bolt would unlock, extract the fired round and eject it downward, completes it's travel backward, then pick up a fresh round on the way forward. The "shell stop" being pulled by the magazine spring, could be a mating part with the bolt, and once the magazine tube is empty, could mate with the bolt and lock it in the open position once the mag-tube is emtpy.

I'm definitely not a firearms engineer, but it's something I cooked up in my head that seems possible at least. We'll call it a preliminary sketch. :) By having a bottom-eject port, ambidextrous safety, and ambidextrous charging handle, the gun could be completely ambidextrous for those with use of only either hand. Thoughts?

Fred Fuller
October 7, 2012, 07:50 PM
Done - good luck with the project.

Smitty in CT
October 7, 2012, 09:08 PM
You may also want to contact Outdoors Without Limits. Their website is: http://www.outdoorswithoutlimits.net/

Kirk Thomas used to work with the NWTF in the Wheelin' Sportsman program, a few years ago, he went off and started his own organization ...

They help people with special needs stay active in outdoor activities, They'd probably have a lot of input regarding a one handed shotgun...

303tom
October 8, 2012, 09:50 AM
Hello all. I am new here as a member on THR but I have read quite a bit on this site and I decided to join.
I am a Mechanical Engineering Technology Student in my final year. Another student and I are researching a project we feel could be quite helpful. We are developing, designing and building a one handed shotgun for our senior design project. More of the design is the stock than the gun. We came up with the idea because we feel it would help single arm amputees enjoy shooting more comfortably and more accurately. We also have tossed around the idea of use in tactical situations as well. It would be nice to be able efficiently use a shotgun without even the slightest thought of using you other hand.
My thoughts are using a Mossberg 500 or Remington 870 for the pump version and the Mossberg 935 or Saiga for semi-auto.

It is a requirement to gain input from other gun-owners and especially amputees.

I am asking you all for your input, suggestions, products you have seen like this(the more info on them the better. I want to make sure I am not taking anyone's patent or anything), which shotgun(make/model) do you suggest for semi-auto or pump and why?

We do already have a basic design and features list, but I do not want to put it up yet because I do not want to influence your answers in any way. I am more looking for accessories, features, or other things you have used that you added on, modified, or that came with a gun(i.e. a stock I bought for a mossberg was everything I wanted in a gun stock except the end of the butt stock was really thin and was very uncomfortable to shoot. Also when it folded the shells wouldnt eject properly because the stock folded in front of where the shells came out). Which things did you hate or love about them, and obviously why?

Thank you all for your input.
This give you any ideas ?

Bovice
October 8, 2012, 12:01 PM
The instructors shot down one of your designs because it was too simple?

I am not the least bit surprised. When I was going through exactly what you are now, we were working on a project that was offered. They told us what we had to accomplish, but not how.

We used the K.I.S.S. approach and that got the professors all riled up. The sad thing is that we have engineers out in the workforce who overlook the obvious because "it can't be something simple". That kind of "showing off" is just what the professors love. They are paid to do research and look impressive. But they are missing a lot of practicality. Shooting down a solution because it's too easy is foolishness. That's not what the real world is about at all.

I am thinking of a stock design that is QD-mounted to the receiver, with a strap system attached to a belt, in orientations to support the weight of the gun and counteract muzzle rise. The stock is "worn" and once it is donned, the user can attach the receiver. It would hold the gun in a constant ready position with an option to quick adjust the harness to lower it muzzle down.

If you would like, I can draw a picture.

AI&P Tactical
October 8, 2012, 12:24 PM
Have you considered a stock with a hook type devise that would go over the shoulder and down the back? I am not sure if I am explaining it correctly.

The stock would still have the standard type pad but the device would hook over the top of the shoulder and down the back shoulder blade to support the weapon. The Stock would have a pistol grip so it is easier to control and lift up and palce over the shoulder. The Hook or brace (in lack of a better terms) would also be padded where in sits on top of the shoulder and down the back shoulder blade.

The weight would be distributed over the shoulder and supported by the pistol grip and to some extent the Hook or brace devise.

Maybe you can take the above and tweak it.

Bovice
October 8, 2012, 01:07 PM
Have you considered a stock with a hook type devise that would go over the shoulder and down the back? I am not sure if I am explaining it correctly.

The stock would still have the standard type pad but the device would hook over the top of the shoulder and down the back shoulder blade to support the weapon. The Stock would have a pistol grip so it is easier to control and lift up and palce over the shoulder. The Hook or brace (in lack of a better terms) would also be padded where in sits on top of the shoulder and down the back shoulder blade.

The weight would be distributed over the shoulder and supported by the pistol grip and to some extent the Hook or brace devise.

Maybe you can take the above and tweak it.
This is exactly what I was trying to hint at. A strap over the shoulder and down the back will support weight of the gun.

AI&P Tactical
October 9, 2012, 11:54 AM
Sounds like we are on the same page. The Hook/brace would simply sit over the shoulder and the shooter can lift the weapon up and away from him for reloading. This means not strap or buckles to deal with.

brodbeckrt
October 19, 2012, 12:33 PM
303 Tom- look at the SPAS-12 Hook
It is similar to that concept. http://gunrunnerhell.tumblr.com/post/32618521229

JAshley-
I like the ideas. Due to time our goal isjust an aftermarket kit to fit an existing gun(with minimal modifications, if any) rather than building an entire new weapon. The ambidextrous ideas I do like a lot. If I had the time/money/licensing to build a custom weapon the possibilities are endless. Thanks a lot for the great ideas.

Smitty in CT- Thanks I will try to get in contact with him.

All thanks for taking the survey. That was more to meet project procedure requirements to put a quantity to a customers opinion. We could have made one that would have taken you a half hour to finish but I feel we wouldn't have gotten as many people to take it. Also posts on here and the other 9 forums are taken into consideration. We would be more than happy to hear anyone elaborate(if they feel the need to) on anything.

brodbeckrt
October 19, 2012, 01:17 PM
I didnt check page 2...

Bovice- I know what you mean... now that we have begun meeting with our assigned adviser, he sees the complexity on the project regardless of the type of action the gun is. That portion of our project is set in stone now so we are just going to have to go with it. KISS is the way I try to live my life. Pictures are welcome.

AI&P and Bovice- We all seem on the same page with using some type of way to fix the rear of the gun to the shooter to allow for more control and help a little with the weight.
Some great ideas.

I'll start giving some of our details:
We discussed some type of brace the shooter could wear and the gun could easily attach and detach from it. The brace would have some mechanism(ball joint, u-joint) that once the gun was attached it would still allow full range of motion. This would also come in to play while reloading. The shooter reload while the gun "hanging" from the shoulder(muzzle down), cycle the action, and move the gun back up into a shooting position.

Inebriated
October 19, 2012, 01:34 PM
I know you've got your idea going.

But I'm just thinking out loud here.

A Saiga would be pretty good if you worked out a real bolt hold-open and bolt-release system that would allow one-handed manipulation. You could do a sling system that would both support the front of the already-short gun, and allow it to hang somewhat tightly to the body for reloading. I would think a vest with one strap coming over the left shoulder to the front of the gun, and another coming over the right to the buttstock. The Left one would support the front, the right one would allow it to hang in a usable position for reloading or manipulation. Since the bolt would be back, all the user would have to do is rock in a new magazine, and use the bolt release once back on the shoulder. Also, the AK mag catch is also great for one-handed manipulation.

brodbeckrt
October 20, 2012, 05:07 PM
Iniebriated- I do like your ideas about the Saiga. Thank you for those. We have our ideas going but nothing is set in stone other than using a pump gun and an auto-loader. Being on a budget I came across a trade I couldn't pass up on a 11-87, and we also got a Mossberg 500. Those are what we are going with. I guess that is now set in stone as well. We are open to suggestions/feedback about anything...

M-Cameron
October 20, 2012, 05:23 PM
i just graduated with a degree in Mechanical Engineering, so if you need any help, feel free to ask.

i know if i were to attempt this, i would do something like this:
http://i264.photobucket.com/albums/ii196/TMSNPR/50411_zps2a0c44b0.jpg


essentially have a shortened buttstocks, and have the trigger actuated by a solenoid with a trigger switch on the VFG.

that should give you a nice compact package that is easily manageable with one arm.

Steve2md
October 20, 2012, 05:45 PM
my suggestion would be a bull pup design, add a little extra weight to the rear of the butt stock to reduce recoil and improve balance further. a single point combat sling will easily facilitate reloads, and can be adjusted so the butt of the gun stays near the shoulder pocket, allowing the use of leverage to move the gun back into firing position. an 18.5 " barrel will reduce the front end weight further, although going up to 20 would be more versatile. go with 20 ga to reduce recoil further. Just my 2 cents

FIVETWOSEVEN
October 21, 2012, 12:45 AM
I have one (a 10-A), and while it's perfectly shootable with one hand, it seems to me it would be hard to fully manipulate safely in a sporting environment with one hand. They're just so SHORT...

If it's a trap gun than it would probably have a longer barrel making it more safe to use.

The biggest problem with a bullpup (especially as a defensive shotgun) is loading it - a student in the defensive shotgun class I took yesterday had a KSG, and he was having difficulties running that gun with both hands/arms working just fine.

Was it a training gap or was it seriously the gun itself being difficult.

brodbeckrt
November 2, 2012, 01:44 PM
M-cameron: I like the idea of the solenoid. we were thinking strictly a mechanical link, but the solenoid my make our lives a lot easier.
Steve2md: we are going with as long of barrels as we can to keep it comfortable. we are moving the grip forward to help re-balance the gun instead of adding weight.
527: You do bring a solid question on the reload problems, as of now we have no plan to modify the reloading procedure. especially if the gun will have some type of strap or brace holding the gun during reload.

Originally we wanted not to modify any part of the existing gun but it looks like I am going to have to shorten the action spring tube on the 11-87
I essentially want to shorten the action spring tube to its bare minimum plus a little "just in case" room. I want to keep the same the length of deformation and same force but shorten the spring. I do not simply want to cut the spring because that doesnt seem feasible.
I do have some questions on this: I am going to have to replace it or build a mechanism to transfer the energy to one or two springs incorporated into the new stock in some fashion. I have some thoughts in my head on ways to do this. Ill have to post up some sketches when I get the specs on the current spring so I can at least have some realistic solutions.
Can I change the angle of the action spring? If so any ideas how much before it jacks everything up?
does anyone know where I could find the actual engineering specs on the existing spring?
Also some of the other specs like the exact length of travel of the bolt(aka the change in length of the spring)?
I am going to find the experimental engineering specs for the current spring later this evening. I just didn't know if it was published in any manuals anywhere?

Any feedback is welcome.

Thanks

M-Cameron
November 2, 2012, 10:15 PM
does anyone know where I could find the actual engineering specs on the existing spring?
Also some of the other specs like the exact length of travel of the bolt(aka the change in length of the spring)?
I am going to find the experimental engineering specs for the current spring later this evening. I just didn't know if it was published in any manuals anywhere?

im willing to bet that if you called up remington and told them what you were doing that they would be able to answer those pretty easily.


as for altering the action spring.....eh, chances are you are not going to be able to alter that and have it run reliably with out considerable re-engineering of the entire action.

brodbeckrt
November 4, 2012, 09:14 PM
im willing to bet that if you called up remington and told them what you were doing that they would be able to answer those pretty easily.


as for altering the action spring.....eh, chances are you are not going to be able to alter that and have it run reliably with out considerable re-engineering of the entire action.

want to keep the same the length of deformation and same force but shorten the spring

Ideally we wouldnt be changing anything since the forces and displacements would be the same. The only thing that would be different would be the spring constant.
Hooke's law for springs:

F(stays the same)=-k(changes in this case) * x(stays the same)

x is the displacement of the spring's end from its equilibrium position
F is the restoring force exerted by the spring on that end
k is a constant called the rate or spring constant

brodbeckrt
November 9, 2012, 12:00 AM
Update... Remington will not give me any info because it is protected.

We are looking more into a redesign of the recoil spring system to make it more compact in the sense that the buttstock will be as short as possible.

brodbeckrt
March 26, 2013, 12:04 AM
Its been a while since I posted. We are currently in the process of building this. here is a render from one of our models:
http://i1223.photobucket.com/albums/dd507/brodbeckrt/96be9acd-ebfd-4e98-8a00-d9dbcec9a97d.jpg

HB
March 26, 2013, 02:45 AM
Looks like a good solution to me. Winchester used to offer a "thumb trigger" .22 rifle. I've always heard it was for WWI vets who lost their fingers during the war so you aren't the first to delve into bringing wounded warriors back into the sport.

HB

Biohazard1993
February 3, 2014, 07:51 PM
anything new about the project brodbeckrt?

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