Reply To: Surprised by scope troubles

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"There is more than you ever want to know in this book."

And much of the info in this book isn't relevant to modern high powered piston guns with synthetic piston seals. This book was written decades ago when they were low powered (relative to modern guns) using leather piston seals. These seals requiring a couple drops of lube down the transfer port to keep the piston seal in good shape and there is a whole section explaining how a large percentage of the velocity was the result of the "dieseling oil".

With more modern synthetic sealed piston guns like my .177 Beeman R9 and .177 HW95, when properly lubricated, there isn't a large velocity added by dieseling oil. I did a velocity test with the internals lubed using molly paste (does diesel a bit), then I completely stripped the internals and only used "powdered graphite" (the kind you puff into locks) which doesn't diesel. The difference in velocity was only 10fps with the higher velocity from the "molly paste lube" (910fps vs 900fps). I'm guessing that the "vapors" giving off from the molly paste did add about 1% to the velocity, however no where near the percentages calculated for the guns of Cardew's era. Matter of fact, I only used the "graphite powder lube" for a few years till I tried the Krytox "space station lube" after reading a report from an airgunner on the forums.

Anywhoo………..

Cardew's "Airgun From Trigger to Muzzle" is available free online as a PDF file so you don't have to spend $$$$ to read………..

https://www.mediafire.com/file/5mcemcyutrm/The+Air+Gun+From+Trigger+To+Muzzle_s.pdf
 

There are "other irrelevant to modern high power synthetic sealed piston guns" tests in the book and it can "read for free" by downloading.