That was one of the four B40's I had at one time. I tried alot of full power tunes on that 177 cal model. At full power I never found a pellet that could produce consistant tight groups.I finally fitted the Macarri R6 spring in it and became a very well behaved accurate gun. I don't remember if it was shooting at 12 FPE when I tuned it or when I sold it. What I would suggest now to you is to drop a Vortek 12 FPE kit in it.It should put you right back in the 12 FPE range and still keep its accuracy. I still have my 22 and 20 cal B40's and both have the 12 FPE kits in.
I was just shooting my 20 cal. over the weekend and I love that gun. Even at 12 fpe the Starlings don't stand a chance at forty yards. John
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