One of the biggest problems with the B3 is the brittle plastic spring guide. All too often, you take a B3 apart and the guide portion is broken off and riding inside the spring. The guide is also very short and could use a couple more inches of length.
To rectify these shortcomings, I cut off the spring guide and preload portion of the stock guide. A 1/2″ hole was drilled through the center of the remaining plug.
I took some 1/2″ round stock steel and cut a 6.25″ length of it. This piece was chucked in my drill, and using a file, sandpaper, and was ground, sanded, and polished. I then slid it into the plug portion I had left of the original guide. A 1/4″ hole was drilled through the steel rod using the pin hole in the plug as a guide. Here’s the two pieces ready for installation:
When the B3 is reassembled, the retaining pin is driven through both the plug and steel portion of the guide. This long guide has turned the B3 into a very smooth cocking and shooting air rifle. There is minimal preload on the spring in the current form. My speed now is 535 fps with 14.5 grain pellets. I just ordered a slightly stronger spring from Vortek, I’m hoping that I can reach a reliable 550 fps in the near future with it.