Nerf Stampede - Internals Guide!

This guide will serve as a reference for the internals of the Nerf Stampede ECS.

For a detailed review of the Nerf Stampede, click Here.

Nerf Stampede ECS - Disassembled




Nerf Stampede ECS - Motor, Circuits & Gears Detail




Nerf Stampede ECS - Plunger & Gears Detail




Nerf Stampede ECS - Plunger Comparison with Nerf Longshot CS-6

(Top: Longshot / Bottom: Stampede)




Nerf Stampede ECS - Plunger Internals Detail

Nerf Stampede Mod Guide!

This Mod Guide will cover some performance mods for the Nerf Stampede.

Mods covered:
- Air Restrictor (AR) Removal
- Plunger Rod Air Release Seal
- Plunger Padding
- O-Ring Replacement
- Voltage Increase
- Aftermarket Spring Replacement

Disclaimer: Modify at your own risk. Modifications may wear out or damage your blaster. Please be careful when using hobby tools!
 

:: AR Removal ::

Step 1: Disassemble your Stampede. Make sure to remove all the screws before detaching the casing.
Step 2: Disassemble the plunger mechanism components and remove the plunger rod from the plunger casing.
Step 3: Use long screwdrivers and a hammer, carefully knock out the Air Restrictor (AR) assembly from both ends of the plunger and bolt.

:: Plunger Rod Air Release Seal ::

Look at the front and back of the plunger tip, notice the 2 air release holes?

For a better air seal, use super glue or epoxy glue to seal both of them.

:: Plunger Padding ::

Without the AR, there is no air buffering system to cushion the plunger on bolt impact.

This results in very high wear and tear on the plunger and bolt casing, by both normal firing and dry firing. Due to repeated direct impacts on the bolt (hence the loud cracking sound during firing) over time, the bolt and plunger may become damaged.

Therefore, padding should be applied to the plunger to help cushion the impact.

In the following photo, i attached a 20mm diameter soft bumper padding to the tip of the plunger.

The 20mm diameter soft bumper pads i used in the above example are from a brand called "Volkmar-Fix", they can be found at most common hardware shops.

:: O-Ring Replacement ::

To test the plunger air seal, block the bolt exit and try to push the plunger rod into the plunger casing, if the air seal is optimized, there should be some resistance in the plunger. It should still be able to move smoothly when the bolt exit is not blocked.

If the plunger seal is loose, simply replace the stock o-ring with a more air-tight aftermarket o-ring.

From my experience, the plungers in different Stampede units can differ slightly in diameter, therefore you will have to test various o-rings to find the ideal ones that fit properly for an air-tight seal.

Photo Left: Aftermarket O-Ring / Photo Right: Stock O-Ring

:: Voltage Increase ::

The voltage feed to the Stampede's motor determines its speed and torque.

To increase the Stampede's Rate of Fire (RoF), simply increase the amount of voltage to its motor.

In my examples, i choose to use 14500 size 3.7V Li-Ion Rechargeable Batteries (Brand: TrustFire / Unprotected versions) for all modded Stampedes.

I prefer to use these type of battery sizes due to their versatility in usage. Because of their AA compatible size, they can fit into multi-slot AA battery holders, and are not just limited to specific hobby or modding usage, they can also be used other devices like CREE torch lights or even to replace normal batteries in compact electronics devices (with proper voltage matching).

Such batteries can be installed in the original Stampede battery sled without additional modification, simply use AA or 2AA to D-battery converters, or use multi-slot AA battery holders.

14500 size 3.7V TrustFire unprotected Li-Ion rechargeable batteries can be charged up to 4.2V each, so i use 4 of them in a 4AA battery holder to get around 16.8V of power.

Notice how little space these rechargeable batteries require. :)

These 14500 size Li-Ion rechargeable batteries are compact and lightweight. Although their 900mAh capacity are low compared to other batteries, i've tested sets at full charge and have managed to fire around 40 x 18-dart clips worth of foam darts before the battery sets require recharging.

That's more than 700+ shots per charge, more than enough for most Nerf games.

As a reserve, i usually just carry an extra spare set for extended Nerf games or when the first set is recharging.

:: Aftermarket Spring Replacement ::

One way to increase the speed of air delivery through the bolt is to replace the stock spring with a stronger aftermarket spring.

There are many different springs with different sizes and spring force ratings. Spring choice will depend on your usage.

The examples below show the stock spring compared with 3 other aftermarket springs.

Photo (Left-Right): Stock Spring, 6kg load Spring, 9kg load Spring, 13kg load Spring.



Tested effects and usage of the various aftermarket springs shown above:

6kg load Spring
- Works with 9V but RoF will be reduced by 50%, recommend >12V for better RoF.

9kg load Spring
- 9V has difficulty moving the plunger, 12V gets normal RoF, recommend >15V for better RoF.

13kg load Spring

- 12V has difficulty moving the plunger, 15V gets normal RoF, recommend >18V for better RoF.

Note that the above voltages are tested with TrustFire 14500 unprotected Li-Ion rechargeable batteries. These unprotected Li-Ion batteries have high discharge rates which are necessary to provide the required torque to the motor to handle heavier spring loads.

Be advised that protected versions or regular Alkaline batteries may not have high enough discharge rates (separate factor from voltage) to enable the motor to pull such heavier spring loads.

For an optimal balance of RoF, range and reliability, i currently use 9kg load aftermarket springs with 16.8V power on my modded Stampedes.

Photo Top: Stock Spring / Photo Bottom: 9kg load Spring

:: Modified Nerf Stampede - Test Fire & Range Testing Video ::

All the above modifications will result in this...

:: Sample Test Fire Data ::

PTG: Parallel-To-Ground (Shoulder height, no elevation)
ATG: Angled-To-Ground (Aimed higher, 30 degrees elevation)

Distance is measured at where the dart lands (Average of 6 darts).

Stock Stampede
PTG = 20 ft
ATG = 30 ft

Modded Stampede (AR Removal & 6kg Load Aftermarket Spring)
PTG = 45 ft
ATG = 60 ft

Modded Stampede (AR Removal & 9kg Load Aftermarket Spring)
PTG = 60 ft
ATG = 75 ft

Modded Stampede (AR Removal & 13kg Load Aftermarket Spring)
PTG = 70 ft
ATG = 85 ft

Note that the tests were done under controlled conditions with customized foam darts. The results are sample estimates for reference (your results may differ depending on materials and mod techniques used).

Nerf Recon "Brass Breech" Mod Guide!

Due to popular requests, here is a mod guide for the "Brass Breech" modification for the Nerf Recon.

This mod is also applicable to other Nerf N-Strike blasters with reverse plunger setups (ie. Raider, Deploy, Longstrike, Alpha Trooper etc).

Background:

For a background of what a Brass Breech is and what it does, please refer to the Longshot "Brass Breech" Mod Guide.

Introduction:

This mod guide will look very similar to the Longshot "Brass Breech" Mod Guide as they follow a similar modding process, but there are some specific differences in parts measurements, positioning and fit that modders will have to take note of.

To establish expectations, due to the smaller reverse plunger setup in Recons (or any of the other reverse plunger blasters), the potential performance gains will naturally be much less significant than in a Longshot.

Important Note:

The "Brass Breech" mod is a more advanced mod project that should only be performed by those who are already familiar with modding the Recon.

For new modders, refer to the Nerf Recon Mod Guide to get familiar with the modding basics first.

Disclaimer: Modify at your own risk. Modifications may wear out or damage your blaster. Please be careful when using hobby tools!

Lets begin...

Step 1:

You will need to obtain 4 different sizes of brass tubes (Brand: K&S Engineering).

The brass tube sizes are: 1/2", 17/32", 9/16" and 19/32". All of them are 0.014" wall thickness. They are usually supplied at hobby shops in either 1 ft or 3 ft length tubes.

Oxidization tends to occur in store bought supplies, so give the brass tubes a good polish with some Brasso Metal Polish, polish both externally and inside the tubes, this helps smoothen out the surfaces for lower friction.




Step 2:

We will work on the barrel and bolt receiver first.

In this example, i'm using 6" of 9/16" brass tube for the barrel.

Take a Rotary Tool with a cutting wheel, and cut a 7.5 cm length bolt receiver half-pipe in the 9/16" brass tube.

Use a sanding bit to round out the edges and corners.

Please be careful when handling such hobby tools, wear protective eyewear, dust masks and gloves.




Step 3:

To help the chambered darts achieve an even tighter air seal, make tightening rings in the barrel.

Use a Rotary Pipe Cutter and create the tightening rings. Just tighten the pipe cutter slightly around the brass tube, then rotate. Do it a few times to create the tightening rings.



Okay, that's all for the brass barrel and bolt receiver, you can put it aside for now.


Step 4:

We will now go on to the bolt section of the breech.

Separately cut out a set of brass tube sections in the following lengths:

1/2" brass tube: 10.5 cm
17/32" brass tube: 3 cm
9/16" brass tube : 2 cm
19/32" brass tube : 14 cm (4 cm for bolt half-pipe)

These are my custom tube measurements for a breech system for the Nerf Recon that can chamber standard-sized darts. In addition, it also features a more secure "half-pipe" bolt attachment point design.

The measurements need to be as accurate as possible. Any variations may affect the overall structure and air seal of the breech system.




Step 5:

Cut the original stock plastic bolt at the section shown below.



Nest all the 4 brass sections for the bolt completely into the plastic bolt end-piece.

Here is my Nested Brass Tubes Cut-Away Diagram for the Nerf Recon:



Use the strongest glue you can get to glue everything together. I use slow-curing 2-part strong epoxy glue. Make sure the glue cures completely for maximum bond strength.

Completed nested brass bolt assembly.



Nested brass bolt internal assembly.




Step 6:

We will now need to do a test alignment of the various components.

Secure the brass barrel inside the original orange plastic barrel by wrapping it with electrical or duct tape to temporarily widen it's outer diameter, so that the brass barrel can be wedged tightly inside the plastic barrel, yet still movable to allow adjustments for test fittings.

Check all the part positions and make sure that a clip with a standard-sized dart can fit nicely into the breech opening.

Note that the 19/32" brass bolt half-pipe will slide over the 9/16" brass barrel half-pipe, which in turn slides into the brass bolt assembly.




Step 7:

To attach the brass bolt to the bolt sled, we will need to cut out the attachment piece from the original plastic bolt.

Position the brass bolt, attachment piece and bolt sled in the casing and note the maximum forward and backward movement of the bolt to find the correct point to attach the plastic attachment tip to the brass bolt.

Note that a segment of plastic behind the attachment point has to be trimmed thinner so that it can slide into the plunger casing properly. Just whittle it down until it fits.

Use some sandpaper to roughen the surfaces on the plastic attachment tip and brass bolt, then use the strongest glue you can get to glue the 2 parts together. Again, i use slow-curing 2-part strong epoxy glue here too. As always, make sure the glue cures completely for maximum bond strength.

This is the section that has to take the most load, especially when stronger springs are used.




Step 8:

Assemble everything together into the casing, note that the pop-up blocker plate mechanisms are all removed, we don't need those anymore.




Step 9:

Test your "Brass Breech" Recon!

Breech open.



Breech closed.



Once you are confident that everything works properly, you can then proceed to permanently glue the brass barrel inside the orange plastic barrel. DIY some plastic spacer rings along the brass barrel to keep it centered within.

Its complete!




Sample Test Fire Results:

PTG: Parallel-To-Ground (Shoulder height, no elevation)
ATG: Angled-To-Ground (Aimed higher, 30 degrees elevation)

Distance is measured at where the dart lands (Average of 5 darts). Brass Barrel Length is 6".

Brass Breech Recon (AR Removal & 11kg Load Aftermarket Spring)
PTG = 60 ft
ATG = 70 ft

Note that the test was done indoors and the results are sample estimates for reference (your results may differ depending on materials and mod techniques used).


Important Usage Tips:

- Clips must be loaded only when the breech closed. This is so that the clip feed-lips can "catch" around the brass bolt for a proper fit.

- For smooth dart chambering process, make sure that foam darts used are no more than 7 cm in length.

- The better the foam dart fit in the brass barrel, the better the range results.

- Due to the smaller air volume of the Recon reverse plunger, using longer barrels may cause the foam darts to get stuck as it doesn't have enough power to propel them out. If that occurs, reduce the barrel length and test again.