montana_charlie
10-09-2007, 02:55 PM
This is a follow-up to my thread in Special Projects http://castboolits.gunloads.com/showthread.php?t=20642 , and is meant to 'test the waters' to see how many others are troubled by 'short brass' for BPCR rifles.
As mentioned in my last post (in that thread), I did come up with a fixture that maintains alignment of the case, punch, and drill bushing while the case is being drawn...when using a not-very-precise shop press.
While Rick Kalynuik and I were working out this arrangement, we also started thinking along the lines of a tool that mounts in a reloading press. That endeavor is beginning to bear fruit, and we are almost ready with a prototype to test.
A reloading press eliminates the need for the 'alignment fixture', and would also cut out some of the individual steps needed in the 'shop press method'. But, the press would have to be a heavy duty unit.
I have serious doubts that my Lee three-hole turret model has the inherent strength to take the strain, but a press such as the old Lyman 'Spartan', RCBS 'Rockchucker', and (newer) Lyman 'Orange Crush' look like they have the muscle.
Guys who shoot fireformed cases without resizing are likely to have 'short brass', as are those (it has recently come to light) who have been using ceramic media in a rotary tumbler.
Besides simply not fitting the chamber well, the main problem is that short cases can also cause leading in the throat.
If you have been finding more lead in your gun than you think you should, compare the length of your brass with the (actual) depth of your chamber.
Yeah...cases can be lengthened by firing with heavy neck tension after full-length resizing, but I have found it takes four cycles to get 30 thousandths of stretch on freshly annealed cases. And, heavy neck tension doesn't produce very accurate ammo for me.
Considering that, the amount of powder and lead 'wasted' to stretch two or three hundred cases gets pretty expensive.
What I would like to find out is...
How many others have found their brass to be shorter than ideal for their chambers?
And, of those, how many would prefer to save their cases...rather than dumping it to buy new stuff?
CM
As mentioned in my last post (in that thread), I did come up with a fixture that maintains alignment of the case, punch, and drill bushing while the case is being drawn...when using a not-very-precise shop press.
While Rick Kalynuik and I were working out this arrangement, we also started thinking along the lines of a tool that mounts in a reloading press. That endeavor is beginning to bear fruit, and we are almost ready with a prototype to test.
A reloading press eliminates the need for the 'alignment fixture', and would also cut out some of the individual steps needed in the 'shop press method'. But, the press would have to be a heavy duty unit.
I have serious doubts that my Lee three-hole turret model has the inherent strength to take the strain, but a press such as the old Lyman 'Spartan', RCBS 'Rockchucker', and (newer) Lyman 'Orange Crush' look like they have the muscle.
Guys who shoot fireformed cases without resizing are likely to have 'short brass', as are those (it has recently come to light) who have been using ceramic media in a rotary tumbler.
Besides simply not fitting the chamber well, the main problem is that short cases can also cause leading in the throat.
If you have been finding more lead in your gun than you think you should, compare the length of your brass with the (actual) depth of your chamber.
Yeah...cases can be lengthened by firing with heavy neck tension after full-length resizing, but I have found it takes four cycles to get 30 thousandths of stretch on freshly annealed cases. And, heavy neck tension doesn't produce very accurate ammo for me.
Considering that, the amount of powder and lead 'wasted' to stretch two or three hundred cases gets pretty expensive.
What I would like to find out is...
How many others have found their brass to be shorter than ideal for their chambers?
And, of those, how many would prefer to save their cases...rather than dumping it to buy new stuff?
CM