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rsterne · Moderator

Thanks for the kind words, but after watching my wife spend 6 years writing a book I have no desire.... Besides, I still have too much to learn....

Bob

redlock · Member

rsterne · Moderator

Unfortunately my notes are not a lot more complete than what I post.... most of the details, and all the important ones I share on the Forums....

Bob

rsterne · Moderator

I finally got a chance to get back to testing the bstaley Disco with the Modded Valve.... I installed a buffer consisting of three 70 durometer #113 O-rings, and started with the striker set Flush with the face of the hammer.... I then turned it in 1 turn CW, at which point the buffer is basically not doing anything.... I shot a string at 2 turns out on the RVA to compare to the unbuffered setup in the last graph.... I then turned the striker out CCW in 1/2 turn increments, and readjusted the hammer spring preload so that the best curve was obtained using a 2000 psi fill.... All shots over 96% of the peak velocity are shown on the graph below....

At 1/2 turn in on the striker, the buffer starts to engage the hammer after the first 2 shots.... Both these strings are lower in efficiency than the unbuffered version.... I was particularly interested in the (purple) string with the striker set flush, as the velocity is almost identical to a stock Disco, averaging 850 fps (23 FPE) with the 14.3 gr. JSB Express pellets used throughout these tests.... The string was 10 shots, the same as what I got in the very first tests with a stock gun, but the efficiency was less, at only 0.98 FPE/CI instead of the 1.05 FPE/CI for a stock Disco.... Despite the fact that we were starting with a gun with much better flow and capable of nearly 100 fps more that stock, the bstaley buffered version fell short of the efficiency of even a stock Disco....

When the striker was withdrawn another 1/2 turn, the shot string increased to 13 shots, but the efficiency was still not as good as previously obtained.... At 1 turn out CCW from flush on the striker, the gun returned 20 shots averaging 709 fps (16 FPE) at an efficiency of 1.36 FPE/CI, which is very similar efficiency to other strings obtained using various buffers at the same velocity.... The bstaley buffer system, at least in a Disco utilizing a 2000 psi fill, really seems to come into it's own when the gun is detuned to 700 fps or below.... Unfortunately, at higher power levels, I was unable to get any improvement in efficiency compared to simple detuning using just an RVA.... It does permit filling to higher pressures than just using an RVA, and in some circumstances that can lead to a couple more shots.... but I was unable to wring any improvement in air usage out of any of the versions I tested unless the power was reduced substantially....

Bob