Author Options:

true semi-auto (nearly) final version Answered

This is the current version of my semi automatic K'nex gun. I probably won't change much unless I run into a big problem. The only real problem now is that the magazine isn't perfect, but that's pretty hard anyway. It works like the prototype I posted a topic about a few days ago ( I deleted that, didn't want 2 topics on the same gun ) So that means by clipping the trigger onto the firing pin. When you pull the trigger it pulls the pin back and then lets go near the end of it's travel distance. Then the trigger shoots back into place again ( if you let it shoot, you can't keep your finger on the trigger at all times ). The only thing about this that I copied 100% is Perfect Duck's handle. I'm really lazy with handles, so credit for that goes to him. I also used decapitated grey connectors in the barrel like on his guns. It shoots blue rods.I can put at least 2 thick rubberbands on it ( I only have 2 left, don't know exactly how much power it can take ), so it can support quite some power. It won't shoot very far because of the friction though. But I think it's respectable considering it's a semi-auto. P.S. I know the picture is bad, I always tend to build these things in the evening so the lighting is pretty bad when I take a pic.



10 years ago

Remind me to post this next weekend. I can't do it right now because I have a lot of school stuff going on, but I have autumn break next week so I'll probably post it on saturday. I don't know if Mepain added anything new to it, but I'm quite happy about my current version.


10 years ago

i don't see how this is semi auto matic.... maybe ppump action.. the reason why is because after i fire, the rod doesn't reclick back in place. How do i get it to go backward?

After you fire, you need to let the trigger shoot back, you can't keep your finger on the trigger. If I wanted it to automaticly click back on without letting it go, it would be extremely weak. And yes there are 5 blue spacers, or 1 grey and 2 blue spacers on the ram in this version. I currently have a version that's a little different so it's more reliable and a little les powerfull.

hmm... well, i guess i'll have to wawit for you to post it lol Good job :)

oh, are there spacers on the ram? i built the updated one from october 6...or is that outdated?

beat you too it! (srry for typo last time, only t of beat showed up!lol)

You didn't beat me to anything, you used You's prototype to create your semi-auto.

ive never seen yous prototype, and i made it around 2 years ago. i kept it cause it was cool. just started to mod it though.and just started account

Aw well, at least your's works the same as You's. And this one works very differently.

well id doesnt really matter if they work different, because they are semi auto. i like your gun, looks better than my handgun lol

It's more powerfull too :p I It doesn't have that handle in the pictures above. I would post it, but I need to see if Mepain made any changes and he won't answer my PM...

Hurray for semi-atuos! So how did you get the firing pin to release?

The pin has three ball joints on it, which hook onto three black hand clips which are on the trigger. The trigger rotates aroind the center of the white connector you can see above it, because I used hinges to attack it to the blue rod on that white connector. This gives the trigger a long motion without angling much, but by the time the trigger reaches the handle the ball joints will shoot of because the angle is too high. The trigger is also pretty easy to pull because it acts as a lever so while it would be hard to pull back with your hands, it would be pretty easy with my trigger.

Well in that case I'll start building it right now. + P

Hope you can figure it out from 1 pic :p I'll make some more today for the topic...

Oh I can... + P But I could always use a few more... Thanks ; )

I already added some new ones. The magazine isn't that good though, but it never really jams bad so it's good enough for now.

You need to get rid of two of the ball joints.

Why that? I did that to support more power.

Because you need to let go of the trigger in order for it to reattach, and I'm not getting any power out of it anyway, even with two of my best rubber bands. I could easily get 30-40 feet with two of the same rubber bands on my sniper. I think the firing pin needs to be a touch longer.

I already said you need to let the trigger shoot into place. And my aim was never really power, even though it can support more then I expected. If you were to make the firing pin longer, it wouldn't get pulled back enough so the ammo won't fall into place. This is also a reason I put 3 ball joints on. Because with only one it would let go of the pin to soon when you put more power on it. And I never really got any power out of your sniper myself. And this also has more friction then a single shot.

You can make the pin longer by moving the whole barrel back two connectors, and it will still work fine. Even with two strong bands and one ball joint, mine will pull all the way back and let go at the correct position. I'm only getting around 2 ft by the way.

I got more out of it with the origional set up. I just don't really see why a longer firing pin would be an advantage.

If you're looking for a better and more comfortable grip design...

Picture 177.jpgPicture 178.jpg

Wow Mepain u are amazing! How can you build this by just looking at the pictures?!! Thats crazy!!!! WOW!

just try, i am mostly done, just need to do some touch ups

What's between the dark grey connectors on the end of the grip, i can't reallys see it from these angles.

I'll try that handle. I guess I have a lot of factors to still look into. Aw well, it's still my first own k'nex gun so I'm still learning. The one ball joint thing doesn't work for me though, it just doesn't grip onto it enough.

When you have a short pin with lots of rubber bands on it, you will get a lot of torque but little speed. If you use a long firing pin with a few rubber bands on it, you will get lots of speed and only a little torque. So on semi-auto guns, they use smaller than normal ammo; which means they don't need torque, they need speed to shoot far. But that's mostly a guess, I imagine it's a good theory though. But I did make a smaller version of my old semi-auto that shot just as well as the larger... So it's I guess it depends on the gun.

Couldn't have said it better myself.

Oh and one more thing, you might want to replace the hinges on the trigger with these pieces, they will support much more power.

Picture 176.jpg

It probably will, the hinges would come of when it was still in prototype phase.

by the way, I just found out that it's best to just use a grey connector on the front of the mag, they both shoot of but the black hinge part does so all the time.

Ok, so I guess yours is looking something like this now. I also put only 1 ball joint on, and that raised 2 problems. It's very weak, and to make the trigger attach without letting go of it takes an insane amount of tension on the trigger, which makes it hard to pull back so your finger starts to hurt. I still think it's better with 3 ball joints, but i will see what I can do about it...

Picture 19.jpg

I put on two, and that works fine. Oh and I didn't shorten the barrel yet, but that'll happen soon.

So, you've only built a long version of my gun right now? And if you only used 2 rubberbands I would like to see how your firing pin looks, because I can't get it to work

Used two ball joints, that is.

2? you said you had 1. anyway, you didnt really asnwer my question about what youve built. Only a long version right?

Yeah, but I'm making it look like yours, and fixing up the trigger a little

I've also made it short again. The longer version proved to problematic. Mainly because the firing pin had so much outside of the barrel, so it wouldn't stay straight, which made it impossible for the trigger to attach. I'd like to see what you're planning with the trigger.

Ok, I currently have it long, I'm trying to see if I can get it to perform like the shorter one


10 years ago

There, I added some more pics. I should really use our digital camera instead of my webcam...


10 years ago

please post soon

I will post it after I fix the big holes in the gun ( 2 minutes work anyway ), and test it for more problems.