When I shot in competition John, I would weigh pellets, check skirts, measure the pellets, etc. And with all that work, if YOU or Idon't do your part,we will have fliers!
The most important factor in any sport is focus ! If you loose your focus for 1/10000th of a second, you or I, can miss the whole darn target. If you listen to some talking, thinking about the last shot fired, your outta there.
Now the use of very good quality pellets will let you know what You and I are doing wrong, when you use top quality, you can see what is going wrong :-)
You must focus on your breathing, your stability, the alignment of your sights to the target, squeezing of the trigger as it is on the target, when the gun fires, and holding your follow through. And doing all this is very hard to do ! But as I say, If you really want it, you have to do it all!
I hope this helps, and as an old master shooter told me many years ago, "it's a poor shooter, that blames his equipment"
P.S. Today if the pellet looks OK, I shoot it, and sometimes I get a 10 ! and if not, I blame myself :(