When I first openned up my BBB, one thing that caught my attention was the plastic washer holding the spring in place and the little nub of plastic it was snapped onto.

I haven't heard of anyone's breaking on them, but I planned on doing a spring upgrade, so to compensate for all the additional stress I decided to throw in a 3/8" washer. It happens to fit over the plastic washer almost perfectly too.

Now, on to the spring replacement...
I replaced the stock BBB spring with an industrial one that i measured to be about twice as strong. Compressed 3", it was pushing back with 30lbs of force compared to 15lbs for the stock spring.

The stock spring is the one on the left, and the replacement one is on the right. As you can see, the replacement is an inch or so shorter so I ended up making a PVC spacer/seat to hold it in place and to ensure complete compression in the cocking pull.
The PVC seat goes in first,

followed by the spring,

then the 3/8"washer and the original plastic mount on top of that. *You could mold epoxy putty around/through the washers and secure them onto the end of the plunger shaft to be extra safe* I'm not quite sure if I want to epoxy it yet so I'll hold off from doing that for now.


Now that that's done, I threw it all back together, got a few fresh darts from my pile, grabbed my tapemeasure, and headed outside to test ranges.

Before I replaced the spring, I was getting around 70' average with an 8 inch nested 17/32' brass barrel shooting level.
Afterwards, the BBB was clearly breaking 100' (not counting dart skipping); I was landing unangled shots at 115-120' tape-measured consistently.
Tasty.