8 replies to this topic

[nematode]

Hello all, I’m a Nerf beginner planning a homemade rifle. I don’t know much about Nerf guns and even less about actual firearms, but my brother has recently become a fan of Nerf blasters. I do have something of a penchant for engineering and design work, so I thought that I would make him a new blaster for his birthday. After looking at pictures both here and on Foam Nation as well as watching several Youtube videos, I think I got how the basics work and drew up my own design. I know that just buying him a blaster would be easier, but I like making things and figured that this would be a fun project.

The idea behind this was to make something similar to a WWII era bolt-action rifle in appearance. Please bear in mind that I DON’T want to make a modded-out killing weapon that will shoot hardened stefans or leave welts with normal darts. This design is not meant to be competitive in large Nerf wars, but to just be a fun design for my brother and I to shoot each other with in-doors at mostly 30-40 foot ranges. Other than the 30 foot minimum range, I want it to be reasonably accurate within this range, especially as the fire rate will be slow.

The key working parts are as follows; the outer barrel (blue), the inner barrel (red), and the bolt assembly (green). The outer barrel has the greatest diameter and fits over the two previous parts. It has a curved slot that the bolt rides in and protrudes from as well as a loading port on top.

The bolt assembly consists of a short stretch of complete cylinder with a long C shaped partial cylinder extending from it. It has a gasket seal around it just forward of the bolt-hole and slides inside of the barrel. The bolt (dark green) sticks through the slot in the barrel and attaches to the bolt assembly.

The inner barrel has the same diameter as the bolt assembly. It sits just forward of the bolt assembly and mainly serves to keep the inside of the barrel at a constant diameter so that there is no step down from the bolt assembly to the outer barrel. (This makes more sense in the diagram) It is fixed to the outer barrel and does not move. If the bolt assembly is thin enough, this piece may be unnecessary.

Pulling the bolt upwards to the left rotates the bolt assembly, rotating the open part of the C to line up with the loading port in the barrel. This allows access inside the barrel so that a dart can be inserted. Pulling it back down to the right closes the gap again. Pulling the bolt back compresses the spring behind the assembly and cocks the gun. Pulling the trigger releases the bolt assembly, which slides forwards, hopefully launching the dart out of the barrel.

I am considering using PVC for the outer barrel and a metal tube for the bolt assembly and inner barrel, but I’m not set on this, so if anyone has any better suggestions, let me know. My main concern is that the loading port won’t seal well enough (I have heard that a better sealed barrel yields better performance), or that the bolt slamming forward into the end of its slot in the outer barrel will cause damage to the barrel over time. If somebody could advise me one way or the other on this and let me know what sort of spring and which sort of barrel material to use, it would be greatly appreciated. If this post is in the wrong section or violates a rule (I didn't see anything in the code of conduct prohibiting such a thread), then let me know and I will remove it immediately.

Please see the attached diagrams below; they should be pretty self-explanatory.
Normal
Breach Open
Exploded Please note that the two black lines on the bolt assembly in the other pictures is the o-ring seal, which I forgot to put into the exploded view. My apologies.
Loaded

Please comment and leave advice/critiques. This is my first time doing something like this, so I could definitely use the advice!

[MAV13]

I have no idea how he put this together, and he has been pretty secretive about it when asked but this one here:
is by far the best one I've seen anywhere. Figured just seeing it may help you out.

[Phree Agent]

If purely looking like a WWII bolt action rifle with mediocre performance with stock darts is your main concern, I would honestly recommend modifying a Buzzbee Range Master cosmetically instead of building a blaster from scratch. The range master is bolt action (although it acts as a pump instead of priming a spring), and also has a breech similar to the one you are describing.

I am not trying to discourage you from building from scratch, I just think for your purposes this is a slightly better idea.

On a side note, threads created with a less than complete blaster, are usually not taken well by the higher-ups even though your diagrams are at least above average.

Edit: Filter fixes.
Edit 2: You sneaky sneaky.

Edited by Phree Agent, 25 July 2013 - 03:53 PM.

[nematode]

I have no idea how he put this together, and he has been pretty secretive about it when asked but this one here: https://www.youtube....h?v=f1G6V6a2T1E
is by far the best one I've seen anywhere. Figured just seeing it may help you out.

It looks like he uses a hopper style magazine instead of loading each dart into an opening/closing breach and that the bolt is slid backwards and then forwards again before firing, instead of just being pulled backwards. I'm not sure how that works, but it seems to be a different design. Given that my bolt is designed to pull back about as far as his, it does however show me that I may have underestimated the launching power of my design, so that is very helpful!

If purely looking like a WWII bolt action rifle with mediocre performance with stock darts is your main concern, I would honestly recommend modifying a Buzzbee Range Master cosmetically instead of building a blaster from scratch. The range master is bolt action (although it acts as a pump instead of priming a spring), and also has a breech similar to the one you are describing.

I am not trying to discourage you from building from scratch, I just think for your purposes this is a slightly better idea.

On a side note, threads created with a less than complete blaster, are usually extremely er0tic by the higher-ups even though your diagrams are at least above average.

Edit: Filter fixes.

I appreciate the advice and I did look at the Buzzbee Hunter and Range Master, but I decided that I wanted to make one myself. I forgot to mention it in the first post, but I will be using streamline darts. Also, I don't necessarily want mediocre performance, I just don't want something that will hurt/injure people.

I'm not sure if "er0tic" was the word that you meant to use. It doesn't make sense in context, so I'm not quite sure that I understand what you are saying.

Edited by nematode, 25 July 2013 - 05:21 PM.

[DartSlinger]

I have no idea how he put this together, and he has been pretty secretive about it when asked but this one here: https://www.youtube....h?v=f1G6V6a2T1E is by far the best one I've seen anywhere.

If you had looked for the video before the update video that you linked to, you would have found this, which is the video that shows how it works. It's extremely simple how it works: when the bolt is pulled back, the plunger catches like a normal SNAP, but the difference is that the spring compresses when pushing the bolt forward. The bolt is prevented from flying back in your face by turning the bolt down, which engages a notch in the plunger. In my opinion, it's a very stupid design: if you bump into the bolt (or if it slips out on its own) when it is primed, the bolt could disengage and fly back into your face. A much better design is to have the blaster prime like a conventional SNAP, i.e., pull-back prime. This is not only safer, because it can't fly into your face, but it is much more ergonomic: the blaster can be anchored against your body when pulling back, but it can only be anchored with your hand when pushing forward. This creates an awkward motion, especially if the spring is strong. (Also, in a previous thread about this exact same design, Carbon mentioned that pull-back priming is less tiring on one's arms than push-forward priming because it uses the bicep rather the tricep.)

It looks like he uses a hopper style magazine instead of loading each dart into an opening/closing breach and that the bolt is slid backwards and then forwards again before firing, instead of just being pulled backwards. I'm not sure how that works, but it seems to be a different design.

See above. I linked to a video showing how it works, and I explained it.

Edited by DartSlinger, 25 July 2013 - 03:18 PM.

[Datum]

Hi, I'd suggest building it off of a Snap Carbine design. It's not bolt action (more of an open-bolt design), but it looks the part if you stick a different stock on it.

What I'd do in your place is build one of these, then create a stock that looks the part and make a proper breech as the barrel. The breech will have to be operated separately from the bolt, however.

Not sure if I'm following it correctly, but if your bolt/plunger is only the same diameter as the darts it fires then I worry about getting enough volume of air to even fire the dart reliably.

Good luck, hope it turns out well!

Edited by Datum, 26 July 2013 - 12:22 PM.

[andtheherois]

Hi, I'd suggest building it off of a Snap Carbine design...

No, stop. I regret advancing the proliferation of this design. It's bad.

The Best way to do it would be similar to the way WES did it, just with more draw. That's assuming you want a NIC worth primary (I didn't read the OP). If you want it to fire out of a breech, you're going to have to rig that up to the action of the bolt. 3" of draw and a LS spring or similar with a 6" barrel might get you 30ft. any more than that will get darts stuck in the barrel. You could even make it clip fed.

[Daniel Beaver]

Don't make a SNAP carbine, they suck.

[Zorns Lemma]

The dude wants something that shoots 30-40 ft and we're talking about SNAP carbines. This thread sucks and represents why we don't do idea threads here.

OP: go modify one of the BuzzBee bolt action blasters.