Originally Posted by live2huntmt
Can you explain to me how the Redding competition shell holders work? I always measure my head space using a Hornady head space kit....and then run my fl die down until I bump my case back .001 - .002 This is all done using RCBS basic dies and shell holders. Thanks
You are doing the same thing by carefully adjusting your RCBS dies to bump the shoulder back. but this is a whole heck of a lot more work and I do not believe it will give as consistent of a bump. Your die is floating above the top of your shellholder when your case is fully engaged within the die at the top of the stroke, and any increase or decrease in friction could cause slightly more or less bump of the shoulder.
The redding competition shellholders are thicker at the top surface of the shellholder where it contacts the die. Your standard shellholder thickness is the most you would ever FL resize based on saami cartridge specs, and the redding kit comes with 5 shellholders with added thickness to the top of the shellholder, specifically +.002, +.004, +.006, +.008 and +010. You could still use your Hornady head space kit to measure your headspace, then you set up your die so that it makes very positive contact with the shellholder at the top of the stroke. Then you select the shellholder that gives .001 - .002 shoulder bump based on your hornady head space measurements.
With the top of the shellholder making positive contact with the die you are getting a much more repeatable shoulder bump, and with a whole lot less work adjusting your die.