Post by Bullshop on Dec 29, 2018 16:21:22 GMT -7
I have been casting bullets for so long that at times I forget there may be much that others have not learned yet so could use help getting started. Today while bumping some round nose bullets into flat nose I thought maybe if I share my procedure someone might be helped by it and even appreciate it.
By the process of bullet bumping you essentially get different nose profiles from one mold. This makes on mold more versatile and usable for different loading applications. For instance as was my case today I wanted to load some bullets from a 90gn round nose mold for my Stevens 32 S&W long. For small game use a flat nose bullet is much more effective if body hits are made but do damage more tissue. A round nose will pierce and is less destructive but will not transfer energy the way a flat nose will. By bumping you get a choice of a less destructive round nose or the more effective energy transfer of the flat nose. Its double duty from one mold.
The bumping process is simple but does require that you have an RCBS or Lyman type lube sizer. For bumping the over rated Star sizer is useless. The process I have developed is to first size and lube in the normal fashion using the sizer die diameter desired for your finished bullet. After all bullets are sized and lubed then switch to a flat bottom top punch that is larger in diameter than the caliber of the sizer die. This so that the top punch will not enter the die. The next step is to lower the depth stop adjuster to the full down position. This will be when you can no longer see any threaded portion of the adjuster protruding past the top of the frame portion that it threads into from the bottom.
The next step is to lower the adjusters that control the bullet ejector pin in the die. This should be adjusted so that the bullet ejector pin will note come up flush with the top of the die when the operating handle is in the full up position. The reason for the is to allow the bullet partial entry into the die so that it will center itself for alignment before any pressure is applied by the ram.
The next step is to invert you sized and lubed bullet and set it nose down into the die, then bring the operating handle to the full down position. At this point you have the inverted bullet fully into the die and the top punch resting on the die top.
Now holding the operating handle with some downward pressure begin to screw the depth adjuster screw upward until you feel it come into contact with the bullet nose. Now to adjust the amount of bumping desired bring the operating handle up enough to raise the bullet inside the die slightly, then in very small increments screw the depth adjuster screw upward a tiny amount each time until you get the desired amount of bump. After adjusting the depth screw upward a small amount bring the operating handle down until the top punch stops on the die top. Check after each try until you have the amount of flat nose desired.
This works great and once adjusted each bullet gets exactly the same amount of bump.
Another point I should bring up is that each ejector pin in the sizer die has two ends one flat and one concave. This gives three different nose shaped from one mold. The concave end of the ejector pin will give a semi round nose finished bullet profile and the flat end of the punch will give an absolutely flat nose bullet profile.
There you go. Its a lot harder trying to tell how to do it than to do it so don't get scared off from trying.
By the process of bullet bumping you essentially get different nose profiles from one mold. This makes on mold more versatile and usable for different loading applications. For instance as was my case today I wanted to load some bullets from a 90gn round nose mold for my Stevens 32 S&W long. For small game use a flat nose bullet is much more effective if body hits are made but do damage more tissue. A round nose will pierce and is less destructive but will not transfer energy the way a flat nose will. By bumping you get a choice of a less destructive round nose or the more effective energy transfer of the flat nose. Its double duty from one mold.
The bumping process is simple but does require that you have an RCBS or Lyman type lube sizer. For bumping the over rated Star sizer is useless. The process I have developed is to first size and lube in the normal fashion using the sizer die diameter desired for your finished bullet. After all bullets are sized and lubed then switch to a flat bottom top punch that is larger in diameter than the caliber of the sizer die. This so that the top punch will not enter the die. The next step is to lower the depth stop adjuster to the full down position. This will be when you can no longer see any threaded portion of the adjuster protruding past the top of the frame portion that it threads into from the bottom.
The next step is to lower the adjusters that control the bullet ejector pin in the die. This should be adjusted so that the bullet ejector pin will note come up flush with the top of the die when the operating handle is in the full up position. The reason for the is to allow the bullet partial entry into the die so that it will center itself for alignment before any pressure is applied by the ram.
The next step is to invert you sized and lubed bullet and set it nose down into the die, then bring the operating handle to the full down position. At this point you have the inverted bullet fully into the die and the top punch resting on the die top.
Now holding the operating handle with some downward pressure begin to screw the depth adjuster screw upward until you feel it come into contact with the bullet nose. Now to adjust the amount of bumping desired bring the operating handle up enough to raise the bullet inside the die slightly, then in very small increments screw the depth adjuster screw upward a tiny amount each time until you get the desired amount of bump. After adjusting the depth screw upward a small amount bring the operating handle down until the top punch stops on the die top. Check after each try until you have the amount of flat nose desired.
This works great and once adjusted each bullet gets exactly the same amount of bump.
Another point I should bring up is that each ejector pin in the sizer die has two ends one flat and one concave. This gives three different nose shaped from one mold. The concave end of the ejector pin will give a semi round nose finished bullet profile and the flat end of the punch will give an absolutely flat nose bullet profile.
There you go. Its a lot harder trying to tell how to do it than to do it so don't get scared off from trying.