21 replies to this topic

[hamoidar]

High-Capacity Mod for the Nerf Praxis Magazine


This mod guid will show you how to transform your 10 disc magazine into a 27 disc high-capacity mag. Even though it holds 27 discs, the magazine is barely longer than a Stampede clip.

First, unscrew your magazine and remove the bottom cap and the lower spring seat. Using a Dremal sanding drum, dremal down all the guiding bars and the protruding edge up 1/4″ into the magazine. Do this to both sides. Next, Dremal the three guide bars on the disc pusher completely off, and round off the bottom edge with sand paper. Sorry there’s not very many pictures, I forgot to take them during the modding process, but I will do my best to explain in detail. Now, you will need an 8″ section of a fluorescent tube protector, and an end cap for it.(these tubes can be bought at any home improvement store, they also come with end-caps)


Using a Dremal sanding drum, sand a 25 degree angle slant all along the inside edge. This will allow the discs to be loaded smoothly. Set this aside for now.




Unravel the wire binding from a cheap notebook, and smooth it out. Take a 36″ piece of 1/2″ pvc and Dremal a slit at one end. Bend the end of the wire into a small L-shape, and slid the wire into the slit. Wrap the wire around the pipe, with about 1/4″ of space between the coils. My spring is pretty messy, but hey, it works.
Drill a small hole where the coil ends, and push the end of the wire into it. This will keep the spring from unraveling.


You can now remove the spring from the pipe. Pre-heat an oven to five hundred degrees, and bake the spring for an hour. (get your parents permission)

Finally, take the fluorescent tube sleeve that you fabricated earlier, and apply hot glue around the top of the pipe. Do this only to the top portion.(about 1/2″ down from the side you dremaled to a slant) Push this end into the bottom of the magazine, making sure to keep it straight while the glue cools. Next layer a good amount of hot glue over the join.



Take your new spring and duct-tape it to the original one, bottom to top.

Drop the disc pusher into the bottom of the pipe, making sure to put it in the right way.(the side with the cut out should face up when you look down the top of the magazine)



Next drop the spring into the pipe and put on the pipe cap.







If all went well the magazine should be able to hold around 27 discs.

Edited by hamoidar, 21 October 2011 - 08:23 PM.

[agc2k]

Nice! I will have to do this to my praxis.

[andtheherois]

Good write up. Though I missed why the 25 degree angle was necessary. I would suggest wrapping it in at least duct tape as those light protectors are a bit flimsy by themselves.

Edited by andtheherois, 21 October 2011 - 06:03 PM.

[meatballica]

Good write up. Though I missed why the 25 degree angle was necessary. I would suggest wrapping it in at least duct tape as those light protectors are a bit flimsy by themselves.

It's so the black piece at the bottom can fit in easier. Though, I'm sure you could just pressure fit it in but that'd cause stress on the clear part and possibly break it. But, I may be wrong. This is just my assumption.

[hamoidar]

It's so the black piece at the bottom can fit in easier. Though, I'm sure you could just pressure fit it in but that'd cause stress on the clear part and possibly break it. But, I may be wrong. This is just my assumption.

Actually, the 25 degree angle is so that the disc pusher transitions smoothly from the original magazine to the extention pipe.

[shardbearer]

Nice job.
Would 1 1/2" PVC work for the fluorescent tube protector? The discs fit perfectly in it.

[hamoidar]

Nice job.
Would 1 1/2" PVC work for the fluorescent tube protector? The discs fit perfectly in it.

Although the discs fit in the 1 1/2 in pvc, the pvc will not fit into the magazine bottom. You could support the pvc from the sides, but this would be pretty messy. The pvc is also much heavier than the protector sleeve.

[Daniel Beaver]

Why are you baking the spring in the oven? The purpose is not clear to me...

[Demon Lord]

By heat treating the spring he made in that fashion, he no longer has to worry about it compressing back.

[KaneTheMediocre]

Although the discs fit in the 1 1/2 in pvc, the pvc will not fit into the magazine bottom. You could support the pvc from the sides, but this would be pretty messy. The pvc is also much heavier than the protector sleeve.

I actually did that a while ago, and made a 50-shot(The method works for any clip size, so go ahead and do a 400 shot if you have a high ceiling) gravity-fed praxis clip. Just use a 1.5" PVC coupler, and duct-tape out the difference between the OD of the stock clip and the OD of 1.5" PVC. Of course, since I didn't have a super-long spring, I had to add weight to the follower, (hot-glue and bbs) then use the blaster upside-down. Feels awkward to hold and fire, but works great otherwise, and the discs seem to fly fine upside down.

[taerKitty]

So much for the cavity being required for aerodynamics...

Could you have loaded the discs upside-down as well?

[Daniel Beaver]

By heat treating the spring he made in that fashion, he no longer has to worry about it compressing back.

I am unconvinced that 400 degrees is enough to properly anneal the spring. My understanding is that you need to get it to just under the austenizing temperature, and hold it there for a few hours in order to release the cold working stresses that got introduced when the spring got stretched. The temperature required varies a lot between grades of steel, but the ranges I've seen are between 500 - 1500 degrees. A 500-700 degree oven might help, but the 400 degrees suggested is almost certainly a waste of electricity. This isn't such a big deal for a magazine spring such as we see in this mod, but I would throw a much more significant shit fit if someone tried to do this with a plunger spring.

hamoidar: let us know whether that spring shrinks back or weakens over time. If it is still serviceable after a year, then all this theoretical rambling of mine is moot.

taer: the cavity in the disk is where the throwing arm pokes up into to fling the discs. I think.

Edited by Daniel Beaver, 26 October 2011 - 03:34 PM.

[Paloose]

Before I say anything else, I'd like to say I'm a student at SIUC pursuing a degree in blacksmithing. On the topic of heat treating steel, there are more or less guidelines to follow unless you have temperature regulated forges and kilns.

To take the stresses out of the metal we normalize the metal by raising it to a temperature so that the steel loses its magnetism and then we let the material air cool and repeat the process twice more. This anneals the metal, makes the steel very soft in comparison to having been work hardened by moving it around through bending, striking, or any other form of manipulation.

On the third heat, after the steel has lost magnetism, quench the metal in water, oil, or brine until it becomes cool to the touch. This process makes the metal hard but brittle, and without the normalizing process you risk stressing the metal so much that it warps or shatters on you.

After you have quenched the metal to make it hard, the next step is to temper the steel so that you draw back some of the springiness of the material and you lose some of the brittleness. A conventional or toaster oven works fine for the tempering process, and the traditional way of telling when its done is to look for the heat color spectrum as it appears on polished steel. Polished steel, when heated gradually, will turn colors from bright steel, to yellow, all the way through blues and purples. Generally in tool making we quench whatever tool we're making when it obtains a straw color, but different colors are used for different purposes.

So, I guess what I'm trying to say is that heat treating is a pretty complex process, and frankly I'm surprised that you managed to keep the temper in your spring. Although the process of winding the spring may have work hardened the wire enough to act as a spring. Just my input though, take it or leave it.

[hamoidar]

I am unconvinced that 400 degrees is enough to properly anneal the spring. My understanding is that you need to get it to just under the austenizing temperature, and hold it there for a few hours in order to release the cold working stresses that got introduced when the spring got stretched. The temperature required varies a lot between grades of steel, but the ranges I've seen are between 500 - 1500 degrees. A 500-700 degree oven might help, but the 400 degrees suggested is almost certainly a waste of electricity. This isn't such a big deal for a magazine spring such as we see in this mod, but I would throw a much more significant shit fit if someone tried to do this with a plunger spring.

hamoidar: let us know whether that spring shrinks back or weakens over time. If it is still serviceable after a year, then all this theoretical rambling of mine is moot.

taer: the cavity in the disk is where the throwing arm pokes up into to fling the discs. I think.

A freind of mine hase taken some classes on metals and explained the same prosess paloose has stated. The spring was heated with a torch, then quickly dropped into a tub of cold water. Then it was baked for an hour at 450 degrees. So far, I haven't had the spring wear out at all, and have used it heavily since modding it.

Edited by hamoidar, 27 October 2011 - 09:58 AM.

[Paloose]

The spring was heated with a torch, then quickly dropped into a tub of cold water.

Be careful about using water that's too cold, that's a good way to stress your metal too far.

[KaneTheMediocre]

So much for the cavity being required for aerodynamics...

Could you have loaded the discs upside-down as well?

The discs don't feed properly unless they are right-side up relative to the blaster. I honestly haven't been able to figure out exactly where the disc is being pushed on, but I wouldn't be surprised if they're being pushed from the inside. I'm guessing the cavity just makes them a bit lighter and cheaper/easier to manufacture. I don't see the cavity being important for aerodynamics, mainly because frisbees seem to fly just fine upside down.

In any case, more thorough testing in good light and open spaces might reveal some disadvantages to the inverted discs, but it certainly won't be bad enough that 50+ shots to a clip isn't worth it.

[Daniel Beaver]

Inverted disks are not at all stable in flight - they have a strong tendency to tilt and curve to the left. By which I mean "you can't hit shit more than twenty feet away".

but I wouldn't be surprised if they're being pushed from the inside.

They are - see the Proton internals below. The blaster is primed, and a disk is sitting in the chamber, ready to be fired. The arm pushes against the inside of disk when it flings it.

Edited by Daniel Beaver, 28 October 2011 - 05:33 PM.

[KaneTheMediocre]

Inverted disks are not at all stable in flight - they have a strong tendency to tilt and curve to the left. By which I mean "you can't hit shit more than twenty feet away".

They are - see the Proton internals below. The blaster is primed, and a disk is sitting in the chamber, ready to be fired. The arm pushes against the inside of disk when it flings it.

part 1 is definitely contrary to my experience. The discs do veer off, but no more than they do right side up.

Part 2 was a very handy picture. It's pretty much what I imagined, but I didn't want to disassemble that far because I'm pretty bad at putting nerf guns back together.

[Daniel Beaver]

part 1 is definitely contrary to my experience. The discs do veer off, but no more than they do right side up.

Try it again. The veering behavior is *very* unambiguous.

[Buffdaddy]

This is a SEVERE necro, but I figured making a new writeup would be pointless.

For anyone looking to do this, Reactor springs (that normally advance the balls) fit perfectly into the T12 guard tube needed for this mod. Assuming slight precompression so that the clip will fully advance, you can fit 33 discs into the tube.

Will add a picture to show it; just thought I'd update the thread with new information.

[Daniel Beaver]

Cool, good to know. Hasbro hasn't (and probably never will) release 20 round mags as a stand-alone accessory, so these modded mags are still relevant.

[BMSCmods]

Very good mod! I would imagine it's much more effeciant in a war environment, but it is a little sloppy on where you connected the existing mag and the clear toob together. But still very nice mod!

USER WAS WARNED FOR THIS POST

Edited by Zorn's Lemma, 20 July 2012 - 06:08 PM.
"effeciant" and "toob" do not constitute english. your post also adds no content to this thread relevant to the current discussion.