I may type a thread elsewhere including more detail about accuracy:
There's a trade-off between FPS and accuracy for several reasons. Some include:
- Increasing FPS decreases the effectiveness of predictable friction at the bucking (i.e. the BB passes a bucking/nub at an angle or to the side)
- High FPS setups will have more vibration in the inner barrel (due to stronger piston slamming) which will decrease accuracy. ***Most people (and I'm confident in saying most people, but not all) know that less vibration is a good thing so they incorporate barrel spacers for instance, but without knowing why it increases accuracy. The ACTUAL reason adding spacers and vibration reducing components of the sort is to aid in stabilizing hop-up spin. I'll refrain from going too much into detail in this thread.
- Airflow from the cylinder is more turbulent at a higher FPS which causes the BB to have a more unpredictable motion in the inner barrel which then leads to unpredictable points of contact (i.e. bounce path.)
- etc...
Obstacles created by a higher FPS can be counter-acted in one way or another, but these higher FPS counter-measures simply mock the effectiveness of a lower FPS system. In other words, a higher FPS rifle will have to be modified to get the accuracy that a lower FPS rifle can achieve.
There are certain components in a higher FPS system that have an advantage over a low FPS system, but in general as an overall system, an
unmodified higher FPS rifle will be
less accurate than an unmodified lower FPS rifle. This of course is assuming that two rifles are internally identical except the spring rating.
As far as BBs are concerned, physics holds that heavier BB's hold more stable spin due to a greater moment of inertia (a.k.a. resistance to changing a spin that was already applied.) Moment of inertia is only affected by two things in a solid sphere, or near solid for this matter, and those two variables are radius of the BB and its weight. Radius is more difficult to change since most people buy their BBs rather than make them, but weight can definitely be selected.
There are other factors as to why heavier BBs are more accurate, but I think this information (rant) may be better suited elsewhere lol.
P.S. Also dependent on the intended distance and FPS, a heavier BB in most cases will actually reach its target faster at further ranges.
I have found this (approximately) holds true:
.27 - 325/.2
.3 - 350/.2
.32 - 355/.2
.36 - 375/.2
.4 - 390/.2
.43 - 400/.2
I believe if everyone were to state values like these they would be different because effectiveness is relative to one's own perspective and rifle.
With that being said, my figures are VERY similar to your figures >

From my data, I personally have values just a tad higher in all categories (i.e. 0.43g- 425FPS), but then again my definition of accurate might be different from yours :yup:
Higher FPS will give more range IF the hop-up is adjusted properly, but once again the trade off (unless modified) will be accuracy.
I'd rather hit someone in one shot with enough force so they call out rather than missing 10 BBs--
each with enough force to blow up mountains. Well... actually... that would be pretty cool:lmao:
I feel like this rant should have gone elsewhere haha. Cheeseman, please let me know if you want me to move this information elsewhere or keep it here since this is technically off-topic lol :tup:
//rant over