Big Bad Bow Mod: Part 2!

Sup lady and gentlemen,

A little while ago, this blog did not exist. It was merely a curiosity in my mind, as my modding was still in its infancy. The BBB was among the first few mods I ever did, and I was satisfied with it at the time. However, nowadays my thirst for power has become insatiable, and some of my older mods are no longer up to my standards. My BBB was ok--the ranges were decent, but it had slight issues with the trigger not catching. Also, the stock plunger head was absolute shit, and sat on an extremely thin portion of the plunger rod that was just waiting to snap off. I knew it was time for an upgrade!


Previous mods:

1. K26 spring replacement
2. Reinforce trigger and trigger catch
3. Shaved down plunger rod
4. Flared out plunger head
5. Double coupler
6. Washers added as spring rests and under plunger head   

Upgrades:

1. Homemade plunger head
2. Plunger travel increase
3. Added dart stop
4. Better plunger padding
5. Fixed priming issue 
6. Unintentionally fixed plunger tube free rotation problem    

Write-up:
First thing's first--open up the BBB and take out the plunger rod.

    
Shave a centimeter off the tops of the "fins" to allow for more forward travel for the plunger rod. Don't shave off too much or the plunger rod won't be able to grab the trigger catch!

Now pop it into a vise and prepare the business end for drilling. I used a 6-32 bolt to secure my plunger head, and a quick Google search showed me that a 7/64'' drill bit was needed for the job. You will also need a 6-32 tap to thread the hole after drilling. My drill press was not tall enough to accomodate the plunger rod, so I had to do it with a hand drill. I DO NOT RECOMMEND USING A HAND DRILL! In the end, I got lucky and got perfect hole right down the center of the plunger rod. Don't forget to tap dat ass.

Now it's time to build the plunger head. From left to right: 1'' fender washer, 1 1/4'' neoprene washer, 7/16'' fender washer, #6 neoprene washer, 6-32 bolt

Grab the plunger rod and slip on the plunger tube followed by a 9/16'' washer (bottom spring stop) and then your K26. Secure the plunger head to it.

After shaving down the fins on the plunger rod, you may notice that the plunger rod no longer catches! No bother--just shave down a nub on either side of the shell to allow the rear part of the shell to slide farther forward.

Now it's time to work on the plunger cap. I forgot my dart stop originally, so I decided to add one by using my shiny new drill press. Overkill? Yes, but using power tools is fun! I used the smallest drill bit I own, which is 1/16''.

Glop some epoxy onto both holes and insert a paper clip through both holes. Make sure each hole is complete sealed and let it dry overnight. After the plunger cap is dry, snip off the excess paper clip and Dremel it down.

Now it's time to add plunger padding. I used a half of a spud gasket for toilets!

Trim it down to size and insert it into the plunger cap. In addition to impact deadening, the gasket will also serve to eliminate a LOT of dead space. Make sure that your plunger head rests slightly in the padding when the cap is on the plunger and the plunger rod is all the way forward. I cleaned the inside of the plunger cap with rubbing alcohol, and the gasket fits in perfectly without glue! I'm confident it won't budge, since I tried to get it out after I put it in and I couldn't.

The epoxy bumps left over from gluing in the dart stop actually prevent the two halves of the shell from closing! The last step is to cut a couple of notches at the front of the shell to fit the bumps. As an added bonus, this step actually stops the plunger tube from rotating freely inside of the shell!

Lube it up and put it back together. I also decided to chop off the front "scope," since it really served no purpose. I think it looks a lot sleeker without it. Now pour yourself some champagne--you're done!

Mistakes I made:
After firing the BBB for a while, I noticed that my velocities suddenly dropped and did not climb back up again. T da B is human just like every modder, so he makes mistakes just like anyone else. Unlike some people, I have no shame in admitting that I was wrong. For this mod, there were two big fuck-ups that I did not see coming:

1. I did not add a "spring spacer" right underneath the plunger head. When I popped open my BBB after raging over my velocities for a bit, I noticed that the top side of my spring was hooked over the plunger head! I didn't think this was possible, since the plunger tube is < 1.25'' in diameter and the washer on the bottom of my plunger head is 1'' in diameter. That's less than 1/4'' of space for the spring to "escape." I guess there was enough wiggle room for the spring to escape. The way to fix this is to add a spacer right under the plunger head that the spring just barely nests over, like a piece of CPVC. This will prevent it from wandering places it should never go.
2. One of the epoxy bumps from my added dart stop eventually broke off from twisting barrels on and off and now a small amount of air leaks out of the hole. Very bad. It's always better to just put a bolt through the whole shell + plunger tube to keep things rigid.

Since I'm going to have to put a bolt through the shell because of mistake #2, I have decided to just max out my BBB with 100% homemade internals. Stay tuned for Part 3!  
 
Final thoughts:
So there you have it--Part 2 complete! My BBB now has a 100% air seal and is much more reliable. It's nice not having to ram the rear part of the shell into the front part to get the plunger rod to catch. As far as barrels, I haven't done too much testing, but I'm using a 10-inch CPVC barrel and it is spitting darts out at an alarming speed.

Daniel Beaver said that BBBs couldn't top 190fps with stock internals--Daniel Beaver was wrong!

I really like this blaster; it's so unique in its design that I must commend Hasbro engineers. It also was much easier to mod the second time around since I finally figured out how the blaster actually works (2 catches!). T da B will soon be moving on to Bigger and Badder things involving sink drains and such. I always end up back in the plumbing section--Part 3 coming soon! :)

~T da B