Many people are NERF enthusiasts around the world, and some actually would like to find a way to make their blasters better. This article will help you make a simple NERF Strongarm into a breech-loading gun (back-loading gun), allow you to prime the gun while the cylinder is ejected, and make the priming mechanism much more comfortable. I'll also go over the steps to change out your spring and make it stronger, even though I didn't do it myself.

YOU WILL NEED

Overall:

NERF Elite Strongarm blaster
Precision screwdriver OR very small screwdriver
A container to keep screws and small pieces in
A well-lit workspace (doing it outside or a well-ventilated area is reccomended)

Breech-Loading Mechanism:

Thin-nosed cutting pliers (AKA snips)
Dremel with varying-width sanding bits
Thin flathead screwdriver (optional)

Ejected-Barrel Priming:

Nothing, really. It's just a simple removal.

Comfortable Primer

Fine-grit sandpaper

Also, two things to keep in mind. One, this is my first Instructable, so it may not turn out well, and two, the photos are all taken from an already modded blaster. That means I won't have pictures of the gun while it's being modded. Thanks, and enjoy!

Step 1: Disassemble the Blaster

Flip the blaster over to the side with the warnings, as this will expose all the screws. All the screws are the same length, so there's no need to organize them. Unscrew the primer first, then unscrew the rest. After that, split the two sides of the blaster shell apart, which will expose the guts of the blaster.

TIP: You can actually leave the screws in the shell, unless you're planning on painting the blaster. I just find it easier to put the screws in a bowl, because then I don't have to align every screw with every slot.

Step 2: Take a Picture of the Blaster Insides

This step might seem useless, but it comes in handy when you are reassembling the blaster.

Step 3: Organize the Small Pieces

There are multiple pieces to this blaster, so I will list the parts and what they do:

Thin orange plate - To be specific, this part has a circle outline on one side and two bars out of the other. This is important if you still want to use the tactical rail, so keep that and the thin spring that goes with it together.
Handle at the bottom of the grip - I'm not completely sure what this does, but my assumption is that it is used for attaching a strap to the gun. If you already have a holster, which you'd have to make yourself, this part is completely useless. It is your choice to keep it. If you don't keep it, you'd have to create a filler, because it leaves two holes in the bottom of the grip.
Cylinder - Completely separable with enough wiggling. This piece is what holds the ammunition before it is fired.
Plunger tube - If you take this cylinder-shaped piece apart, you will get the tube and the plunger. The plunger has a spring in it, along with an O-ring. There is also an air restrictor. Many people remove this, as they think it allows more air through. That is correct, but I think leaving it in there is a better idea. What the air restrictor does is not only hold back air, but it also allows you to dry-fire safely. If you remove this and dry-fire, there is a chance the tube will rupture, therefore making the blaster inoperable. So I would leave that in.
Barrel rotation mechanism - This just rotates the barrel.
Safety rod - This stops you from priming the blaster while the cylinder is ejected.
Priming indicator - This shows that the blaster is primed. It also actually primes the blaster, so keep that!

I'm not sure I covered all the parts, but that's the majority of them. Also, the plunger tube, rotation mechanism, and safety rod should come out as one piece.

Step 4: Breech-Loading Mechanism 1

First, you need to wiggle the barrel out of the blaster. To do this, you remove the front holding part from the cylinder and wiggle the cylinder out.

Step 5: Breech-Loading Mechanism 2

Remove the front of the cylinder. The separation is where the thin line is. I'd include a picture, but it was hellishly hard to remove again. I'll just show where to separate it. There will be a screw. Unscrew it, and the grey piece will come off. Once again, I cannot show this, as I couldn't take the cylinder apart.

Step 6: Breech-Loading Mechanism 3

To make it breech-loading, there is a lot of cutting and sanding. In the picture above, you will see that the chambers are completely empty. On a non-modded blaster, there will be a piece that cuts the back of the cylinder in half. Find the part of the barrel without the protruding cylinders. Use the snips to cut those out. Then, use a thin sanding bit with the Dremel to smooth down the edges.

Step 7: Breech-Loading Mechanism 4

Now, if you put the cylinder back together, you will see that the bullets don't fit from the back. This can be fixed easily. Find the other part of the cylinder and, with a low speed setting, use your Dremel and go in circles around each chamber, repeatedly testing if a bullet will fit through them. Once each chamber has been widened enough, completely put the cylinder back together, screws and all. Now you just reattach the grey piece and insert it back in the gun!

Step 8: Safety Rod Removal

This is very simple. I would provide pictures, but I already threw the rod in the trash. All you have to do is take out the trigger and remove the rod running from the cylinder back to the priming indicator. Then, you can put the gun back together, unless you are deciding to replace the spring. In that case, skip the next step, do the optional step, then put it back together to do step nine.

Step 9: Making the Primer Comfortable

This is very simple as well. Some people do this, others don't. It all matters on your opinion. For me, when I prime the blaster, it hurts. I researched and found that most people have the same problem. The reason this problem exists is the grip on the primer itself. The grip is amazing, don't get rid of that. What hurts is the end of the grip. The grip overlaps onto the side of the primer, which - if your hand is big or slides on the primer - the overlapping grip scratches your hand. The simplest solution to this is to sand down the edges. If you refer to the picture above, you will see the side is completely smooth due to sanding. If I didn't sand, there would be little protruding lumps, which scratch your hand. Once again, doing this is based on your opinion, whether your hand doesn't slide or you don't mind the pain, or whether you don't like the pain.

Step 10: OPTIONAL: Replacing the Spring

If you decide to replace the spring, first you need to buy either a replacement spring or upgrade spring. I'm pretty sure the spring has the equivalent of 5kg of force. If you are going to modify your spring, I'd recommend a 6kg spring or 7kg spring. All you have to do is remove the spring from the plunger and put the new one in. Then re-insert the plunger.

Step 11: OPTIONAL: Increasing the Air Seal

There are two ways to increase the air seal. One is to buy a thicker o-ring, and the other way is a bit cheaper. Take the plunger out, and remove the o-ring. Add a thin line of electrical tape and put the o-ring back on. Then re-insert the plunger.