Reloading 556 - Interesting Observation - But Begs The Question
Quote from donaldwatkins on July 21, 2023, 12:37 pmI just recently started to reload 556 brass. I made a few rounds, went to the range and most of them ended up failing to fire and most getting stuck in the chamber. After putting the problem reloaded rounds into a case gauge, I realized the the brass was not getting fully resized properly. I guess I should have checked this before hand but just assumed. This was puzzling because the die was set per instructions. Raise the cam to full press, screw down the die until it hits the shell plate, then back off a smidge.
After closer inspection and some digging, I found that there is a deflection in the shell plate, even though it is properly seated. That being said, I had to screw the resizing die down a smidge more, meaning it was now past the point where it would hit the shell plate. The deflection was enough to keep the shell plate from hitting the die and now the brass was getting resized properly. It fits in the case gauge perfectly. All rounds fire and eject.
This begs the question - is this deflection coefficient an indication that something is starting to wear out somewhere in the press? Or is it a normal occurrence on 556 brass? Somehow I feel that I shouldn't have to screw the die down past the point of contact, even though its thousandths. Have any of you experienced this before?
I should also point out, I do not have this issue with 270, 22-250, 40 or 9mm. Just seems to be with 556.
Thanks for your thoughts.
I just recently started to reload 556 brass. I made a few rounds, went to the range and most of them ended up failing to fire and most getting stuck in the chamber. After putting the problem reloaded rounds into a case gauge, I realized the the brass was not getting fully resized properly. I guess I should have checked this before hand but just assumed. This was puzzling because the die was set per instructions. Raise the cam to full press, screw down the die until it hits the shell plate, then back off a smidge.
After closer inspection and some digging, I found that there is a deflection in the shell plate, even though it is properly seated. That being said, I had to screw the resizing die down a smidge more, meaning it was now past the point where it would hit the shell plate. The deflection was enough to keep the shell plate from hitting the die and now the brass was getting resized properly. It fits in the case gauge perfectly. All rounds fire and eject.
This begs the question - is this deflection coefficient an indication that something is starting to wear out somewhere in the press? Or is it a normal occurrence on 556 brass? Somehow I feel that I shouldn't have to screw the die down past the point of contact, even though its thousandths. Have any of you experienced this before?
I should also point out, I do not have this issue with 270, 22-250, 40 or 9mm. Just seems to be with 556.
Thanks for your thoughts.
Quote from ARMTGuy on July 21, 2023, 3:55 pmThe Dillon Precision die instructions have always made it clear that what you described is merely THE STARTING POINT for die adjustment. And what you are doing is not flexing the shellplate. You are lifting the toolhead to its upper limit, and ensuring the shellplate is pressed fully down to firm contact with the top of the platform. Nothing is worn, this is typical for bottleneck rifle cases.
The Dillon Precision die instructions have always made it clear that what you described is merely THE STARTING POINT for die adjustment. And what you are doing is not flexing the shellplate. You are lifting the toolhead to its upper limit, and ensuring the shellplate is pressed fully down to firm contact with the top of the platform. Nothing is worn, this is typical for bottleneck rifle cases.
Quote from donaldwatkins on July 21, 2023, 10:14 pmThanks for the information. I never thought about the tool head moving too. All is well. Thanks again.
Thanks for the information. I never thought about the tool head moving too. All is well. Thanks again.