I have a Rock Chucker that is on the order of 20 yrs old. I bought it used when I got into reloading about 5 1/2 years ago.
When I first started I was loading "mainstream plinking ammo": 9mm, .223, .38 Spcl, etc. Over the last 2-3 years I started dabbling with higher precision stuff (first with a stock Rem 700 in .243) and now I have a Kelbly/Brux in straight .284.
As I started paying more attention to jump, CBTO measurements, etc. I noticed I could change seating depth by up to .003-.004 based on how hard I pressed on the press handle after it was bottomed out. I've lived with it - and haven't considered it a big deal. At this point I was using standard RCBS .243 dies with the threaded seating stem rod.) Most recently with the .284 when I seat bullets (Redding Competition die) I've set it up so I just gently let the press handle bottom out. And this provides good repeatability.
This morning I was trying to figure out why I was getting variability in my sizing operations. Shoulders were being bumped up to .001-.003" more than i wanted in some cases. Then I recalled my bullet seating experiences. I tried sizing while focusing on not pressing down on the handle after the handle initially bottomed out. Doing that resulted in sized cases coming out MUCH more consistently.
Is this extra ram movement based on handle pressure common in presses like a Rock Chucker? Overall I'm pretty much getting the results I want to have. Between that, and knowing this situation exists, I can very much live with it for the time being. I guess in the larger view I'm wondering if I should start thinking long term about replacing this press.
Thanks!
CG
When I first started I was loading "mainstream plinking ammo": 9mm, .223, .38 Spcl, etc. Over the last 2-3 years I started dabbling with higher precision stuff (first with a stock Rem 700 in .243) and now I have a Kelbly/Brux in straight .284.
As I started paying more attention to jump, CBTO measurements, etc. I noticed I could change seating depth by up to .003-.004 based on how hard I pressed on the press handle after it was bottomed out. I've lived with it - and haven't considered it a big deal. At this point I was using standard RCBS .243 dies with the threaded seating stem rod.) Most recently with the .284 when I seat bullets (Redding Competition die) I've set it up so I just gently let the press handle bottom out. And this provides good repeatability.
This morning I was trying to figure out why I was getting variability in my sizing operations. Shoulders were being bumped up to .001-.003" more than i wanted in some cases. Then I recalled my bullet seating experiences. I tried sizing while focusing on not pressing down on the handle after the handle initially bottomed out. Doing that resulted in sized cases coming out MUCH more consistently.
Is this extra ram movement based on handle pressure common in presses like a Rock Chucker? Overall I'm pretty much getting the results I want to have. Between that, and knowing this situation exists, I can very much live with it for the time being. I guess in the larger view I'm wondering if I should start thinking long term about replacing this press.
Thanks!
CG
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