More of an "in progress" build than a finished design, this has been a constant on and off project.
Essentially this feed mechanism is the same as a click pen. When the bolt travels back, the rotary
System rotates 30 degrees, and then when the bolt moves forward, then the last 30 degrees of the
System is rotated. In hindsight, this may be pushing the limits of reliability. If you don't pull the bolt
All the way back, you may get a miss feed, or possibly, irrevocably damage the rotary system.
Getting past that, I designed this (similar to all of my other designs) on a the cheapest of a shoe string
Economic budget. All of the metal is standard thicknesses and the springs were ones I already had.

More on all of this later (As I said, this is an on and off project, and one of many) but as for now:
Enjoy the pictures!

(Open the pdf with adobe so that, when you click the image, it activates and turns into a 3d pdf. 3d pdf's
are rotatable, and you can hide/isolate individual components.)

DE23C_Belt_Fed_.410.zip

Thanks,
Tanner Frisby

Very cool. Besides how neat the concept is, I have never seen the 3d in Acrobat. Nice work.

I have been waiting for this one for a while! I am looking forward to seeing it come to life. Even if time does not permit now, maybe after college?

You do great work Tanner!

Update: Due to design flaws (the kind you only notice after you have invested time and resources) I have completely redesigned this.

New design: Smaller, Lighter, Better operating system, Magazine or Belt fed, Pistol Grip instead of Spade Grip.

I have a 3 day weekend this weekend and intend to get a sizeable chunk of this project done.

87669_3_Trunion_Pictures.zip

E4758_Belt_Fed_.410_bore.pdf

I'll try to document this project and make a write up of it when I finish (similar to Orian Hammer's BlowbAK)

Thanks,
Tanner Frisby

Sweet! I have been waiting a very long time to see this thing run buddy!!!!

Did you ever get a response back from ATF yet on the other deal?

No, sadly I haven't received a response. This weekend will be the 12 week mark. What would you recommend?

I cant look at the pics my wifes comp. wont open.
Oh well that said: i have a silly suggestion, have you taken a look at the Nerf belt fed i believe it uses a rotary style feed mech.
As i said silly Maybe but if it works we can always work back from plastic to steel.
I keep one around to get after my son and his friends during a Nerf attack by them. With the extended belt i made Daddy usually wins...
As long as the batteries don't run out.

"Age and treachery will always overcome youth and vigor"

Anyway good luck looking forward to seeing this when i get my wifes help with the comp.
Ryche

Put another 3 hours into it tonight. This is looking promising. I've just about finished the receiver. I think I will start with the side plates or the bolt next. I've included the cut outs I've been using to shape the c-channel and DOM pipe. I used the same CAD program from the 3d pdf to print off the to-scale cut outs, and then I just tape them on top of the steel and shape away. Due to school, my shop hasn't been used in weeks, so it was nice to get back to shaping and welding.

(Yesterday's pictures scaled down
50% to fit reasonably. Probably should go down to 33%, sorry for stretching the page)






(Today's pictures)





Thanks,
Tanner Frisby

Looking very good! As far as suggestions, hurry up and wait! Or call and bug them if you can. I was reading it can take usually 3 months for a response so it should be coming soon.

Stark raving bonkers...

Can't wait to see it in action.

Another update for today's 3 hours (33% size seems to work perfectly):







I shaped the basic cut outs of the five plates (left, right, front, back and cover). The sun is setting on my drive home, and by the time I get to work on these it is usually dark. I do my cutting in a separate area (along with my welding) and the separate area doesn't have very good lighting. For this reason, I sharpie off the paper cut out onto the steel and then contrast it by placing masking tape up to the cut line. I can see yellow against dark grey better than I can see black against dark grey. Also, tape doesn't fade and disappear from the heat generated by angle grinding. After they get cut with an angle grinder, I took them in to my main workshop and file the rough cut to the tape line. (TEDIOUS!) I still have one long side of the cover plate (center) to file, but ran out of time today.

Hopefully tomorrow I can finish shaping the plates and break up my bolt design to a composite structure (I believe Orian Hammer's terminology was 'laminate' bolt).

Thanks,
Tanner Frisby

Another update:

I cut out the intricacies of the left and right plates. I started by taping the cutouts to yesterday's steel strips, and then using a Dremel and an angle grinder, cut out the unremoved material. Since I tape instead of glue, the paper cut out has a tendency not to stick to the metal, so I used bands of tape to apply pressure to the paper. After cutting and filing, I was able to mock up a teaser using two drill bits to hold the left and right plates vertical. Also, before I realized my original design was a no go, I invested in some 3d printed parts (such as a belt feed aligner). I have incorporated a few of those into this redesign.







Also, I was determined the best way to chop up the bolt and have rendered it in a 3d pdf:

AFD12_Bolt.pdf

I still haven't finished the details pertaining to the extractor claw or the firing pin, but I have left plenty of room for filling with lead to reach the ideal blow back weight (~5lbs )

Bad news is that the three parts (receiver, left plate and right plate) don't line up well, which probably means one of them is off. Hopefully it is a simple mistake that a little filing can fix, but I don't think it is.

I don't think I will be in my shop tomorrow, but maybe Monday.

Thanks,
Tanner Frisby

Looking dang good! I find that 3 or 4 crooked's tend to make a straight! LMAO

I will pray for you that some filing or maybe weld up a hole or 2 and re drill will fix it.

Very cool project and concept.

In Alibre cad (the software I use), their is a sketch tool called "project to face". When in an assembly (a conglomerate of individual parts) you can use this sketch tool to have one part "cast a shadow" on another part. I use this method a lot to design devices (such as firearms) that have many interacting parts.

Assembly's also have the option of "anchoring" parts such that they can't move. This is convenient when a non moving part is placed where it should be, but is an impediment when using moving (or rotating) parts and while editing parts.

What happened was the right side plate sub-part was not anchored and was slightly moved on accident . Clicking and dragging can rotate/pan or, based one exactly where you click, move a sub-part. After slightly moving it, I then projected the receiver to the right side plate.

Long story short: the right side plate was the issue caused by extensive negligence. I spent most of my shop time identifying the problem and fixing it. I also mounted the side plates to the trunion (10 screws per side).



My process for attaching the side plates to the receiver is as follows:

1. Fine sharpie outline of where the receiver should touch the side plate.

2. Clamp receiver to side plate based on the markings.

3. Measure depths from the top of the side plate down to the receiver and compare to theoretical. Acceptable tolerances are + or - 0.015. Both side plates must have consistent off-age polarity.

4. Tack the first side plate and, using a drill bit or spare rod. check to see how perpendicularly the holes line up. If acceptable, tack second side and recheck perpendiculality.

*step 4 required 3 attempts before I got it right.



After both side plates are tacked, I plotted out the ideal place to drill and tap the screws that will attach the side plates to the receiver. I broke my only 1/8" drill bit on the second to last hole



This overview shows the row of drilled holes (after a quick trip to Lowe's) along with the filing adjustments I made to the receiver so that a belt fed from the right side plate will no longer snag against the receiver. Ugly, but it will work for me. Also pictured in the back ground is the old Version 1 model, and about 2/3rds of my work shop.



And finally, this is where I have left it. I drilled and tapped the 20 holes so that they accept 1/4 - 20 machine screws, and I bore the front plate so the barrel can now pass through.

Tomorrow marks the new grading period in school, so I don't anticipate too much physical (non-digital) progress before my Thanks Giving Break (starting next Wednesday). Stay tuned!

Thanks,
Tanner Frisby

Another update:



I made the pivoting groove track[/technical term] initially out of mild steel (like the rest of the build), but it completely lacked precision. The groove was non-linear and had a ton of wiggle room. I don't think I could have made it any better with the tools currently at my disposal, so I opted for a different material. I had some 1.5mm ABS sheeting off hand, so I decided to try that. After cutting out the blank, I decided it was way too flimsy. My only alternative was G10 sheeting. I absolutely hate messing with G10. It is very toxic and smells disgusting and you can never get rid of the dust. With that said, I had amazing results with it. It is almost as strong as the mild steel version, yet many times easier to machine.



I thought I might mention my method of welding clean right angles. I believe the picture says it all (even though the picture is after the weld was complete and ground down).



Pictured is the construction of the chassis[/more correct technical terms]. I'm sure it has a proper name, but I don't know it. Since the groove track (orange) will be hanging upside down from a 6-32 screw, this piece prevents any sagging. This piece also aligns the cover when in the closed position because the outer bounds of the chassis come in contact and align with the left and right side plate. The process for determining depth is to use a scrap piece of the G10 and also a sheet of paper folded over twice (some wiggle room) as a spacer and then weld shut. Also pictured is the .1" displacement of the orange piece. This is needed because the link that is connected to the orange piece is .1" and is sandwiched between the cover and the groove track.



Here is the groove track and the chassis.



Most up to date mock-up.

Not shown:

I also integrated a firing pin and extractor claw assemblies into the bolt. I had left an anticipated area for them, but until now, I hadn't actually worked out all of the details on them. Now I can start physically making the bolt. Similarly, I have left ample space for a trigger group and pistol grip and butt stock, yet I haven't begun to think about the details on them.

I also identified more discongruities between the moving pieces in the cover assembly (similar to the right side plate / receiver discongruity). Hopefully this will also have a relatively simple fix.

If you know the correct terms for any piece I have mislabeled, please correct me. I'd much rather call the pieces by their proper names.

Thanks,
Tanner Frisby

I like the way this is coming together! BTW, since you are designing it, you can call the pieces whatever you want!

I think it might be a feed arm but i am not 100% sure! Pivoting groove track works just as well.

I like thr PGT term myself. and as long as you know what it is who cares what the fu***** its called.
I like to make up tech. trade industry terms myself.
This looks great and i'm really looking forward to the next step.
Ryche

time for me to step up & stop just lurking this awsome build i must agree with the others your design & build call em what you want  

i know this is a belt feed 410 but have you given any thought to maybe a clip feed 45lc convertor/addaptor i love 410/45lc combo imho you get best small game & short range big game for shtf & in a shtf situation  bad guys go down hit from either opption

just m2cw

great build so far by a talented young MAN

Another update:
School has been overbearing recently and has severely restricted my free time. With that said:



These are the rough cut outs of all (well, most) of the sub pieces that make my bolt. Also included in the image is the cut out template.



Tonight I finished filing the sub pieces down precisely to slightly excessively to the desired shape. One or two of the pieces have already been drilled, and the rest have been center punched. The cut outs only last one trimming/filing/cutting, so I usually go through three copies per sub assembly (rough cut, fine cut and layout comparison)



Also, the bolt is my first design that utilizes milling. As you can see, my multibillion dollar industrial milling machine does a bang up job. (Harbor Freight's Cheapest drill press paired with a vibrating china made cross-vice and a bargain pair of TiN end mills).
I welded over the slop and fine tuned with extra passes. I thought I went slow enough (my bit never heated up) but I managed to dull my 1/2" endmill. It was probably the plunge drilling. Anyway, can I sharpen it with a file or is it shot? Also, after welding and fine tuning, I can get the claw to firmly hold a round.

A pressing concern: (puns )
I am still weary about the bolt's weight. Orion Hammer's write up on the blow back bolt weight ( here ) is phenomenal, but I worry it doesn't take into account work done by the main spring. I am only now taking Mechanical Physics and have much to learn, but I worry a 2.8 lbs bolt weight (while acheiveable as I plan on filling this to some extent with lead) is too much. For starters, the DOM barrel I am using has an inner diameter of .501" whereas the .410 bore has, wait for it, a .41" diameter. This to me seems like a massive reduction of pressure. Also, my main spring is an ar-15 buffer spring (main spring, bolt spring, something to that effect). It is about 12" long and, in the chambered position, will be about 6" long. When charged, the spring will be fully compressed to about 3" long. Now I could trim the spring as needed, but I would rather not. Without a spring constant or any other data on this spring, I can't anticipate the work that the spring will do against the bolt and thus re-calibrate the bolt weight. Any help here will be much appreciated.

Thanks,
Tanner Frisby

Its been a while since I updated this (5 weeks ).

Well, with the possibility of new weapon bans on the horizon, I figure I might as well get solid proof of receiver construction date. I'd like to preface the craftsmanship with either "I'm not done with that part yet" or "It will be hidden / not viewable when completed / ready to fire."

As of right now, I have lateral motion of the pawl when the bolt is cycled ( I tried to illustrate this with a 1/3 pull of the bolt, also please note the ambidextrous charging handle), a functioning semi auto trigger group (I have plans and holes drilled for a safety, but haven't made it yet), magazine release and all other obvious things shown. The bolt doesn't have an extractor claw (I tried 7 times before giving up. It has the available cuts made to accept a claw if that day ever comes) and the firing pin is spring assisted (not free floating, but I don't know the term for it). The barrel is held in place by two set screws and the cover (top plate) can only be removed upon removing a side plate. The side plates are bolted (10 screws each) to the receiver and back plate (1 additional each). The back plate is bolted to the side places and welded to the receiver. The front plate is welded to the right plate. The barrel must be removed before the right side plate can be removed. The barrel gaurd/shroud/grip is held in place by one set screw. The main spring (ar 15 buffer spring) is held in place by a dowel which screws into the back of the bolt and (will) enter into the butt stock through a hole in the back plate. While I hope to finish this project up soon, I have decided to try to not "rush" this build in hopes of better quality.











Sadly, I fell behind on (stopped) the in-progress-pictures. As a consolation though, I do plan on making a write up on this build after I finish it. It should be easy enough to recount how each part was made after the parts are finished.

I still have to:
attach a ratchet system to and beneath the pawl
pistol grip
front grip
butt stock
safety
belts
magazines
ammo cans (inserted into mag well, hold belts and spent rounds)
mounts (I was thinking a trailer hitch mount and a tripod mount)
integral bipod
excessively large muzzle brake (because of the MASSIVE forces coming out of the .410 shot)
scope (see above reasoning)

I'm sure I'm forgetting some things.

Thanks,
Tanner Frisby