Sunday, October 7, 2012

Big Bad Bow Mod!

I started this blog after I started modding, so I've already finished a number of blasters. I suppose a good start to this blog would be to go over what I've already accomplished, so here it goes. The Big Bad Bow originally came out in 1998 with the Hyper Sight line of blasters. It was essentially the Bow 'N Arrow with a trigger, which improved accuracy quite a bit. The earliest versions were purple and had a very strong stock spring inside. The Big Bad Bow (also called the BBB or 3B) has a very large plunger tube and is a direct plunger system, which is why I decided to buy it in the first place. This blaster has some of the most interesting and unique internals of any Nerf blaster. For one thing, it has two different catch mechanisms--one for releasing the plunger rod and another for keeping the blaster primed. Although the looks are a bit weird, it feels very comfortable and shoots like a champ!

Here are the mods I did for this bad boy:
  1. Replaced stock spring with a K26 off
  2. Removed bow arms and arrow holders
  3. Reinforced trigger catch with J.B. Weld
  4. Shaved down the corners of the plunger rod to allow 9/16'' washer to slide over it
  5. Hot glued a paper clip ring around the plunger head to flare it out
  6. Reinforced the plunger rod with various washers. This is what my plunger rod looks like from back to front: 9/16'' washer, K26 spring, 3/8'' washer, orange spring rest, 3/8'' washer, plunger head.
  7. Universal coupler connected to front of plunger assembly that accepts CPVC or PVC connections. I will go over universal couplers in a separate post.
I have not busted out my chronograph yet to measure feet per second since I just sent my Chrony F1 back to be fixed, but velocity is definitely at least 150 fps for some shots by my estimations.

Some things I would do differently if I got another BBB to mod:
  1. Don't forget the dart stop! I forgot to add the piece of wire that prevents the dart from getting sucked backwards into the plunger tube. I usually epoxy a piece of paper clip to the back of my couplers. Now I have to make sure I prime the blaster before I attach a barrel, or use a barrel that already has a dart stop.
  2. Build my own plunger head. The BBB uses an old style of plunger head that kind of sucks. Nowadays, Nerf uses O-rings which can produce great seals. The old skirt-style plunger heads are rather flimsy and usually aren't stretched wide enough for a good seal. I would probably make the "washer sandwich," which is a rubber neoprene washer sandwiched between two metal washers. You can attach this to the plunger rod by epoxying a female hex standoff to the end of the plunger rod, or by drilling a hole and using a hand tap.
  3. The gun has trouble catching the hook on the end of the plunger rod with the trigger catch. There is something I might try to solve this problem; I could sand down the back side of the plunger rod hook to make it catch sooner. If that doesn't work or it seriously starts compromising the structural integrity of the end of the plunger rod then I might cut it off and epoxy in an "extender" piece.
  4. The plunger tube recently broke free of its hot glue binding and now freely rotates in the shell. This is very annoying when you are constantly switching out barrels. I might solve this by epoxying a piece of metal to the plunger tube and something to the shell the nests the piece of metal to keep things rigid.
Note about hopper clips:
I have not had success with hopper clips in this blaster. I have read online that many people have problems getting the BBB to work with hoppers. Apparently RSCB clips work a lot better, and you can integrate them right into the shell! Maybe if I get another one I'll try it out.

To be continued...
This mod is part one of a three-part trilogy. Here are the links to Parts 2 and 3:
Big Bad Bow Mod: Part 2
Big Bad Bow Mod: Part 3


  1. RSCB's works best for BBB's, anyways great post. Keep up the good work!

    1. Thanks a lot! Hopefully my blog will end up as nice as yours, iModify. If I get another BBB I'll definitely try the RSCB clip.