Drop it down to 115ish, you may have to bump up your internal adjuster a touch, it's a balancing act between the pressure and your hammer spring, a very very very fine balancing act. Once you get your hammer spring set it's 'easy' to make the adjustments. You can lower your reg by firing a shot and IMMEDIATELY turning in the screw a bit, say 1/4 turn. IF you have the old style plastic regs all bet are off, the new ones are brass and Delron. They HAVE to be almost flush with the end like the RH one the middle one is too high, needed to sand it down, impossible to get enough pressure, it's THAT critical. Test your gun at the lower pressure, increases your HSA out 1/4 turn at a time until the max speed is reached, back it off slowly to find the max speed, then dial it back (in) a bit more, VERY VERY small amounts, You may well find that the pellets want to go faster than 900. It's a balancing act between the 2nd reg pressure and the HSA. You don't need the dial at 7, it's perfectly ok to be at 4. 7 is my max speed for heavier pellets/slugs I'll dial back for 18.13 AEA pellets (my personal favorite, 930ish FPS). It's hard to explain and there are a ton of posts here on how to do it. A few of the internet videos are very good. You can't make a mistake unless you crank the reg in under full pressure. Then the fun begins.
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