First Nerf-related post!
As an avid Nerfer, one of the most frequent problems I come across is jamming when I fire my bullets. This often results in damaged darts that cannot be restored to their full capacity. With a new pack of Nerf Streamline Darts (SD), I did a few tweaks to boost their durability and performance.
Why does jamming occur?
Jamming occurs when the darts (red) do not fit into the breech (white space behind dart) or when they do not have a circular but more of a oval or elliptical cross-section. This results in interference from the dart below the primary dart with the operation of the plunger tube (blue). Refer to Figure 1 (Source: nugget1123 – nerfsg forums).
Figure 1: Step-by-step guide to damaging your Nerf Dart
You can see how the secondary Nerf dart is caught in the breech as the gun is primed. And then as you use superhuman strength to overcome the resistance, all you do is destroy the dart.
Typically, these darts are already damaged and have ‘ripped’ ends. The more damaged your dart is, the more likely it will be damaged in the future. Sucks huh?
Prevention is better than cure!
Repairing your dart offers limited advantages for the time you invest into it. I find it easier to just strengthen brand new darts so that they last longer.
Figure 2: Set of three Nerf Elite Darts
The first dart from the left is a standard Elite Dart (similar to Streamlines). The second has had its rear reinforced by PVA glue. The third dart has been reinforced by PVA glue and a layer of sticky tape.
PVA Glue
I found that adding PVA glue to the end of the dart increased its ability to maintain its shape by resisting the compressive and tensile stresses applied during priming. This meant less jams and faster firing. Refer to Figure 2.
Figure 2: PVA reinforced end
However over time, the the layer of PVA glue would deteriorate and crack. A disadvantage of PVA glue was that although it improved resistance to deformation, it increased the brittleness of the foam. So when the layer of PVA glue cracked, so did the ends. Figure 3 shows the end result. 😦
Figure 3: ‘Ripped’ Ends (Top and Bottom of Dart)
Sticky Tape
To resolve this, I added a few layers of tape around the front and end of the dart (the front I will explain in a later post).
This had two main advantages.
First, the tape would maintain the shape of the cross-section (initially strengthened by PVA) much better by applying a compressive force towards the centre of the dart’s cross-section. This compressive force would be able to resist stresses on the dart during priming minimising damage.
The second advantage was that it would taper the end of the dart (reduce the total cross-sectional area). This decreased the chance the breech would ‘catch’ the second dart during priming. As you can see in Figure 4, the tape has wrinkled after the dart was caught in the breech. Notice also how the cross-sectional shape of the dart remains unchanged.
Figure 4: Tape and PVA glue reinforced end
Figure 5 shows how the darts sit well in a Nerf Clip
Figure 5: Standard Nerf Clip with Modified Darts
A further advantage of tapering the ends was the increase in volume of the rest of the dart as mass was forced away from the ends. This meant the modified dart fit much more firmly within the plunger tube and flew with greater power and distance when the gun was fired (notice the slight bulge to the right of the tape in Figure 4).
In addition by using tape to replace the exterior foam at the end of the dart, the friction between the darts had been decreased significantly increasing the ease of breech operation.
Essentially, by modifying the dart, you can improve not only its performance but also its durability.
Hope this post was informative and assisted you in your Nerfing!
The next instalment will examine the observed and potential disadvantages of this modified dart.
Summary:
- Nerf Streamline Darts jam due to irregularly shaped cross-sections which interfere with priming operation
- It is more effective to reinforce the darts by strengthening the ends with tape and PVA glue
References:
http://nerfsg.freeforums.org/nerf-recon-dart-jam-issue-t625.html
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