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Rotary magazine Answered

So I've been trying to build again. I had an entirely different project in mind but I noticed that the teeth of gears fit into the grooves of rods. I was experimenting with it quick to see if a gear would make a decent pin lock (it doesn't). I kept toying with it until I went off on this entirely random tangent without planning on it, hence the mismatched colors for the one slot connectors. 

Anyway, this is a rotary magazine. Similar to a drum magazine, it's just a magazine in cylindrical form factor rather than a linear form factor. I'm not sure if anyone was able to successfully make one before. This version in particular stores 12 usable blue rods and one extra one that can't be fired. It has a ball joint connector to act as a paddle to help ensure the rods continue feeding without skipping teeth. I don't have many dark grey connectors but otherwise I'd scale this up using red rods and then store yellow rods. It'd be more useful as it'd fit more nicely with a connector body. Currently to maximize ammo use, I'm trying to fire directly from the magazine without feeding it further vertically. The problem is it's obviously an awkward fit. If you imagine a typical 5 layer gun, it'd fit in between layers 1-2 and 4-5 about halfway each. It's entirely doable, but just doesn't look too pretty.  

It's nice in that it allows you to store a fair amount of ammo in a relatively compact amount of space, but it's otherwise not a practical storage solution as is. Aside from just trying to figure out how to attach it to a gun, figuring out how to reload it conveniently would be difficult. It -might- be more useful if it can be turned into a roofed, removable magazine. Then at least you can preload them first. 

I hope someone can give a weapon that uses this a shot. Perhaps a bolt action for better performance. And again, I'd scale it up to store yellow rods so it's a little easier to use in a standard connector body. 

Here's a quick video demonstration and a look inside it at the end:


Nice concept! If it's alright with you, I may try incorperating this in one of my next guns.

Great! I will see what I can do with it.

BTW, I am currently searching for ideas of something to build and post
with K'NEX. If you have any ideas, please visit (www.instructables.com/community/Any-Ideas-On-What-I-Should-Post) and
you can tell me your idea in a comment. If I build and post your idea, I
will give you partial credit.

By the way, you can see a working example of the concept on my Barackuda, which is posted in another thread.

Don't have any ideas at the moment but I'll let you know if I do.

Yes, I saw that thread. I will take another look at it.

Great! I look forward to hearing your ideas when you get some!

I hate how slow in progress I've been, off and on, but I'm determined to finish something for once. I don't know if I mentioned, but I'm working with BM to help finish up my weapon. If I can remember after work today, I'll get some pictures and start a new forum topic. It's in a state I'm more comfortable showing, but it still needs some work. Mostly I need to figure out a good bullet lock + feed ramp that still maintains decent accuracy and range.

Man these forums are dead, it's rather sad. Anyway, weapon progress:
-Front of the body is completely finished, at least until test firing
-Back of the body is pretty much finished, may make small adjustments
-Magazine is finished. Removable and preloadable
-Handle is mostly figured out, though I'll be making adjustments for comfort
-Trigger works but could use a little improvement
-Bolt is figured out but not built yet
-Still need to build stock

Great, it seems like the build is starting to come together! Have you given any thought to using a thumbhole stock on it?

I have a gun that will be out fairly soon. It is a weird but cool looking gun that seems like it came straight from JonnyBgood's K'nex designs. It has a unique trigger system that blocks the pin far back, giving it about 6 3/4 inches pin pull, which is nice. At the moment it is only single shot, but I might convert it to bullpup or free flying slingshot.

I've not only given it thought, it's what I'm building at the moment. The way I designed the back of the gun and bolt requires it because I like my guns compact.

Sounds interesting, I'll be keeping an eye out for it.

I'm quite fond of them as well. Part of the reason the PDR-C is my favorite gun is its stock and front grip designs. So I'm doing something pretty similar to my PDR design.

Neat. The gun I have to post has a thumbhole grip, but some of the connectors are rough on the back of my hand when I hold it, so i might have to try to fix that.

Good luck. It's always been a challenge with K'nex given we don't have any nice way to make smooth, comfortable curves aside from bendies.

Yesterday evening I fixed it with pink flexie rods. It doesn't look as good, but I can't post a gun that rubs the skin off of your hand, can I?

Did you get to test the range of KK's TR before your fin ammo was ruined?

I've taken the pictures for the gun its self, I just need to take instruction pictures. I may just do internals, 'cause I want to lengthen the barrel and turn it into a free flying sling, or I'll try a rail gun. Again. I think the pictures are going to come out OK this time.

I already built a slingshot and hated it. It was ugly and had a bad trigger.

But I'm posting a gun with a removable 5.56 magazine. It's pretty nice.

Eh, I've seen some pretty nasty looking handles posted back in the day. Everyone has different hands and find different things comfortable. But do what you can, you'll find a balance.

Well I didn't measure it exactly. I only have so much backyard space to fire in. All I know is that even fin ammo still suffers from a fairly quick drop. While it may maintain a horizontally straight trajectory, it doesn't maintain a flat trajectory for long, requiring you to tilt the gun to compensate. It starts to get harder and hard to aim accurately the more you have to tilt it, so I'm less interested in its max possible range over it's practical, effective range. Perhaps if I have free time, I can take a video comparing different ammos, their ranges, and their accuracy with the little space I do have.

Right now it is a mix of comfort and looks, not great at either but OK. I just finished rebuilding the trigger to make it a little more reliable.

OK. All K'nex ammo drops off pretty quick. I think white rods with fins have been mentioned before, and those could shoot extreamly fast and flat since they are so light. I don't think that they are very balanced for fin ammo use, though. I've found that at about 50 feet and 5 bands it shoots plenty flat, but not too good after that. The only way to get long range is by angling the shot fairly sharply. It can get extreme range, but the effective range is rather short. I think the farthest I got shooting without an angle was about 100 feet. And the last 40 or so feet it was flying somewhat low.

Have you thought of using the street to test ranges? That's what I tend to use with a gun that shoots more then 70 feet. I shoot and measure where the ammo first hit, not where it lands, of course. It's pretty easy on my street, since there are a bunch of lines of street tar (?) across the road, so I can remember withing 10 or so feet where it hit.

You do have to be careful if there are people walking their dogs, or are pushing a stroller with their baby in it. That can get akward really fast.

I think that with the right setup, finned blue rods would probably be the best balance, but they're probably the most annoying ones to find in the grass aside from greens obviously. Maybe I'll try out finning different rods and see what sort of results I get. What I'd really like a is a repeating slingshot for finned ammo at some point.

My neighborhood is oddly shaped, so I don't even have that much room in the street, nor would I want to test there either. It's a rather family friendly neighborhood and I doubt anyone would take too kindly to me shooting projectiles out in public space.

Yeah. If I had a TR built I would mess around with that, but I don't. Indoors finned blue rods would be nice, nearly impossible to dodge and they don't have enough weight to do much damage.

OK. I live in a fairly nice neighborhood too, with a lot of families and elderly people. I just have to risk it to test ranges. Of course they would be less disturbed by me shooting plastic darts then a 21 year man shooting plastic darts.

Hopefully Killerk will be kind enough to send you the next one if he does it again. I'll definitely try out finned blue rods. Perhaps give finned yellow rods a chance as well.

Yeah, 22 now actually. =P Even if it looks colorful, people wouldn't know exactly what it is that I'm firing and it'd look odd for me to be firing it blindly down the street.

Yeah. The issue is everyone knows that I am a KILLERK fan, and might say that it does everything he says it does, and there might be a problem with folks believing me. But what would be sweet is an SRV3 for testing.

True. That might freak a few people out. I think at one of the big K'nex wars the cops got called onece.

Beautiful design great idea! How have you been? I wish I could have given you a more finalized TR including better trigger and band placement along with updated pin. This sorta build inspired me to get back into building. I think it's time to schedule a war asap. I have been busy with family new job and a baby on the way buy I'll always have fun building. I have some younger cousins that are getting into Knex too! Soh it's fun watching them learn to build!

I hope there is a big turnout for the war this year. I'd be interested to see what you build next. Congratulations on the baby! You may be one of the first K'nexers to have a son/duahter.

Been pretty good. Living the pseudo-bachelor life with my actual bachelor friend in his house, which typically means just gaming or learning more software development stuff in our free time, but occasionally I come back around to building.

Feel free to send more things. =P I accidentally left my fin ammo outside while testing different ammo, so the tape shriveled up. I really ought to get some tape to make my own fins. The trigger has been fine and was an easy replacement. I've noticed a few things in dinking around with your TR that have led me to rethink how war weapons should be designed. For example, your band placement on the firing pin tends to put a lot of stress on it, causing it to bend. Not only does this make me worry about the integrity of the piece, but it causes extra friction in the barrel, something that I could feel while decocking the gun.

Congrats on the kid, man. Have any names in mind? And that's great, we could always use more builders. I got one of my brilliant cousins into building K'nex and he's made quite some interesting things. Still hasn't quite figured out guns aside from some primitive designs, but he tries. Eventually I'll show him this website.

Yeah, I believe a blue rod version was done very similar to mine long ago. Anyway, sorry I didn't get you pictures yet. I'll try to remember to do it when I get home today. I have the body of a bolt action, the feed ramp, the bolt handle, the trigger, the front mount for the magazine, and the basis of a handle and stock but I'm open to change those. And then obviously I have the magazine figured out. It's a yellow rod version that also has a pusher setup that can be locked before inserting into the gun. I still need to figure out how to latch the back of the magazine on to make it removable, a bolt pin, and a good stock. Those all involve roughly the same area, so you can completely rework that for all I care. You'll see what I mean when I get the pictures.

Man, I was on a building buzz and then just sort of fizzled out. I'll try to get back to building soon. I rather like the yellow rod version. I figured out how to put a band and mag lock on it. It's just tricky making it removable for a gun. The bolt action I was working on just wasn't quite turning out, but I'm not quite ready to give up yet. If I still can't figure it out, then at the least I'll post pictures of what I was attempting and then move on to something else.

I've got a start to something better than my last attempt. Just a few tricky parts left. I'll probably have to collaborate with someone so I don't just straight give up on it if I can't figure the tricky parts out.

If I can't find help, I'll throw in the towel and post pictures of what I have. Currently asking Red. Though his time is sparse so I don't know when to expect a reply let alone if he'll be able to help.

Alright. I would also try Blue Mullet, since he leans toward innovation. He does use a disturbing amount of cut pieces, but you already know that. LTB might also want to help.

He's my second choice. I figured he's probably busy with his war gun, though. Red and I tend to have some similar building philosophies. But I'll take help from just about anyone depending on who's available.

if this could be made at a larger scale it would be really practical in knex wars or recreative use

Eh, it sounds nice in theory but the reliability of such a mechanism gets spottier the larger you try to make it. Because the shell isn't perfectly round, it doesn't always ensure the rounds are snug in the teeth of the geras. I already had to include a paddle on mine to make sure it'd feed without skipping. But if you rely too much on this, then there'd be a lot of friction inside making it hard to drive it with just a wound band alone. Otherwise, I'd agree, I like how compact this is compared to a turret or magazine for the capacity you get.

Dude, this looks so sick! Great start man, I can't wait to see where ppl go with this!!!

Sadly, the idea was done before, though I still don't think it was used successfully. I'm having problems using it myself, but perhaps you could do something with it or something similar.

Working on a bolt action gun now. Decided to use a yellow rod magazine instead. I came up with an interesting trigger setup, not too happy with it, but it works given how little space I had to work with. So now all I have to do is come up with a stock and bolt.

Funnily enough, I decided to go back to using a blue rod magazine. Ironically, the main point of me using a yellow magazine was that the red rods would clip in with a connector body, but then I ended up not even doing this anyway. I just didn't like the way the gun was turning out otherwise. I'd like it a little shorter and to have more room to work with. I'm going to try to make the blue rod version of the magazine removable.

I'll post a picture of my scrapped version either after I succeed with the blue rod version or after I've given up altogether.

More funnily, I changed my mind and decided I liked the yellow rod magazine better anyway. I prefer yellow rods, it gave more room for your hand to support the weapon, and it was a little more reliable. And while the gun looks weird, it gives it character, doesn't look much like any other bolt action (as is the worry making a bolt action that somehow it'll just be another ZKAR). Here's hoping I don't have any more setbacks and can get a picture soon.

I'm looking forward to it. I might need to try a blot action myself.

As am I. I don't know if you already know the story but I've been trying to make a bolt action I liked for years ever since I came up with its modern form. This will be a weird way to finally make one, but I'm hopeful. Definitely, man, give it a shot.


Not sure how it will work out, since most of my attempts at being innovative end up as disasters. I want to stay away from charging handle bolts like the plague, simply for originality. It would be fun to have a little bolt on the side of the gun that would be pulled and released to chamber a round, or use the trigger guard as a way to chamber it.

I like your thinking. So basically have a realistic charging handle instead of a big ol' bolt handle? Try it out, see what you come up with. Even if you don't make a powerful weapon, it'd be a novelty for something realistic. Bonus if you use shelled ammo to get that satisfying ejection effect from pulling back the charging handle.

Yeah, I'll at least give it a try and see how it works out. You nailed it, bolt handles are never much more the ZKAR knock offs.

When you were developing a BA with SK did you come up with the style of bolt handle on the ZKAR, or was that Zak's invention?

To be fair, the bolt handle was his own creation. I recall SK came up with one that wasn't all that strong and required supporting it with your hand in a specific way. I was otherwise struggling to come up with a good idea for one. Zak's was simple and got the job done. I came up with a couple alternative designs since then but obviously haven't used any. I have yet to design a new one for my new gun. I'll try to make it unique.

OK. Some of SK's old stuff is pretty cool, albeit not the best looking.

(Man, I wish we'd just have a chatroom sometimes)
Yeah, I really miss some of the older K'nexers. He was a classic innovator. Just think up a concept and get it working for the sole sake of it, even if it's not all that practical.