Excellent post Tominco!
I just got the FX Streamline in .25 Laminate. I have now shot about 400 rounds of JSB super heavy 34 grains. (I did shoot some 25 grains as well but not enough to form a solid opinion.) My rifle came with no pamphlet whatsoever. There was just a generic brochure from AOA. So I had no idea how to adjust the hammer spring. My first impression of this gun was very favorable. Real solid construction and tight fit at all places. The Italian Minnelli stock is very nice. Trigger is excellent; a little bit better than the AAs510 (which is ever so creepy but still good).
My first impression upon shooting was is that was it was crazy fast on power three. I didn't have a chrony set up, but just from experience at shooting the Mrod, with which I am very used to by now at 50 yards, I could tell it was somewhat north of 950- and it did bark. Groups were good at 50 on power level two, 3/4" or so. On power level three they were pretty erratic. At 85 yards, a range I like on my sizable lot, they were all over the place. I mean 5 and 6 inches. After 30 shots , I noticed a decided TWANG that was not present on the first 30 or so. Since the pressure is regulated and should be consistent up to about 45 shots (from what I hear), I couldn't quite figure that one out! I don't think it is a defect, just an oddity I guess. I think I am burning up too much air on power 3. I want to get to the velocity you mention, just a little under 900.
Did you get an instruction sheet? Is the hammer tension spring the only adjustment? The Mrod has a hammer travel as well as you are probably aware. I know I will have to play around myself with the Chrony, but about how far did you take the screw out (out I assume?) to come down to the point you are now at?
I think it is going to be better as things settle down and especially if the velocity comes down as you so well described! I love the shot count on power one; it's great for close to about 100 shots. Real sweet for shooting around 20 to 30 yds. And just in passing it is set up with a 30mm Aeon scope with half mil increments.
Yours is a lovely gun by the way; you must have had to slip and extra fifty bucks for that walnut ! But I really like the laminate stock and it'll never warp.
Don Galfur