In some of my past post in the air gun section of this forum I've mentioned that I've been shooting my existing break barrel air rifle long enough that I've noticed that I'm getting Points of Impact shift depending on how my pellets fit into the chamber. Generally speaking, if the pellets drop right into the chamber with no thumb or finger pressure my points of impact tend to be high and to the right.
If the pellet drops in and stops with the skirt flush with the face of the chamber my points of impact seem to hit the target high but not quite as high and still a little to the right of my point of aim. This is from 25 to 30 yards.
When the pellets require just the slightest bit of thumb pressure to get them to seat flush with the face of the chamber, this is when I get the best accuracy. To that end, I decided to try making myself a set of pellet sizing dies in order to get my pellets' to all have the same outside diameters so as to require that slight bit of thumb pressure to seat in the chamber. Since I normally shoot the 14.3 grain Crossman Premier Hollow Points (the cheapest ones I can buy) and they are not the best Quality-Control-Wise, making this set of pellet sizing dies might serve to keep me from having to buy more expensive pellets that have better quality control to keep them a little more geometrically uniform from one to the other.
The dies are not the best looking by any means but I'm hoping they will prove the concept of bringing these otherwise cheap pellets to a state of uniformity that will help increase the accuracy of a given tin of pellets. There have been times when I've bought a new tin that shot like a laser out of my Octane air rifle. Other tins have shot like absolute KaKa. Still others have given me some pellets that shoot to point of aim and some that shoot high and to the right. It all hinges of the fit of a given pellet into the chamber.
I'm hoping to be able to do some testing of this concept in the near future. I'd like to be able to increase the accuracy of my air rifle if I can. I know that human error can play a part in the high-and-to-the-right misses but like I said, I've shot enough pellets out of my Octane to know that not all of those points of impact shifts are my fault.