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Some aspects about accuracy dependency on case sizing
I have some thoughts about sizing aspects, and I want to formulate them in terms of questions below, feel free to address any of the questions. Each question comes with explanation and maybe some examples in order to express idea/concern.
1) Does different case sizing affect accuracy a lot? For example, let's say one group of cases were sized 0.003" back, and another group of cases were sized differently; 0.003", 0.004", 0.007", 0.005", 0.008" back, in other words, inconsistent sizing. So do you think this will greatly affect overall MOA (given all other conditions same) for second group?
2) I have a Lee turret press, and I insert turret with screwed in sizing die into it. One thing I noticed is, when I pull lever and the bottom side goes up pushing the case into a sizing die, the turret makes around 1-3mm movement between its base, i.e. gets pushed back. That is understood, because turret is inserted into some sort of a cutout inside a frame of the press and there is some walk inside. But what I was wondering is, could this be another variable to inconsistent sizing of cases? we do know that it also depends on how much force applied and how the lever is pushed, but at the same time, if we assume similar force you apply with hand, does the turret type press introduce additional variability in sizing? Would it be better for even more consistent sizing just setup a separate non-turret, i.e. fixed type of press and screw in the sizing die in it and not take it out (say, this is a permanent sizing setup for 6.5G or something).
3) Let's say we intend to size a group of cases 0.003" down from the measured fired case, and we have a fixed type press with sizing die in it. If we perform sizing operation on 100 cases after the sizing die was screwed in and set, do we expect all 100 cases to be sized exactly 0.003" down? (or whatever amount we set it to). Or is the variation there normal? At least for me, even though if I try to have equal movement with my hand pulling the lever... I do see a variation. And now, I want to understand better what is the reason for the variation, and first thing is *Force applied while pulling the lever down*, or in other words, how much force you apply when pulling lever down. Is that the case or not?
If the answer is yes, then it turns out not to be a very easy task to maintain consistency, even after you set certain setting for sizing die.. (or could it still be that my negative experience in seeing variation comes from Lee's turret press? ref. question #2).
I actually remembered once some guy I know told me he worked on some sort of industrial factory, and they had something like "industrial hammer" or whatever that thing is called, and he said it was operated by pressing a pedal which translated the movement of a very huge hammer, so he told me there was one guy who managed to "close a matchbox" using that mega huge hammer. It was extremely difficult because you had to apply a proper amount of controlled force on pedal in order not to smash that matchbox and just close it. So I recalled it now after thinking about sizing operation, in a way that some certain controlled amount of force has to be applied to sizing in order to get consistency. anyway..that was just thought, but I hope question is understood.
1) Does different case sizing affect accuracy a lot? For example, let's say one group of cases were sized 0.003" back, and another group of cases were sized differently; 0.003", 0.004", 0.007", 0.005", 0.008" back, in other words, inconsistent sizing. So do you think this will greatly affect overall MOA (given all other conditions same) for second group?
2) I have a Lee turret press, and I insert turret with screwed in sizing die into it. One thing I noticed is, when I pull lever and the bottom side goes up pushing the case into a sizing die, the turret makes around 1-3mm movement between its base, i.e. gets pushed back. That is understood, because turret is inserted into some sort of a cutout inside a frame of the press and there is some walk inside. But what I was wondering is, could this be another variable to inconsistent sizing of cases? we do know that it also depends on how much force applied and how the lever is pushed, but at the same time, if we assume similar force you apply with hand, does the turret type press introduce additional variability in sizing? Would it be better for even more consistent sizing just setup a separate non-turret, i.e. fixed type of press and screw in the sizing die in it and not take it out (say, this is a permanent sizing setup for 6.5G or something).
3) Let's say we intend to size a group of cases 0.003" down from the measured fired case, and we have a fixed type press with sizing die in it. If we perform sizing operation on 100 cases after the sizing die was screwed in and set, do we expect all 100 cases to be sized exactly 0.003" down? (or whatever amount we set it to). Or is the variation there normal? At least for me, even though if I try to have equal movement with my hand pulling the lever... I do see a variation. And now, I want to understand better what is the reason for the variation, and first thing is *Force applied while pulling the lever down*, or in other words, how much force you apply when pulling lever down. Is that the case or not?
If the answer is yes, then it turns out not to be a very easy task to maintain consistency, even after you set certain setting for sizing die.. (or could it still be that my negative experience in seeing variation comes from Lee's turret press? ref. question #2).
I actually remembered once some guy I know told me he worked on some sort of industrial factory, and they had something like "industrial hammer" or whatever that thing is called, and he said it was operated by pressing a pedal which translated the movement of a very huge hammer, so he told me there was one guy who managed to "close a matchbox" using that mega huge hammer. It was extremely difficult because you had to apply a proper amount of controlled force on pedal in order not to smash that matchbox and just close it. So I recalled it now after thinking about sizing operation, in a way that some certain controlled amount of force has to be applied to sizing in order to get consistency. anyway..that was just thought, but I hope question is understood.
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