Rock Chucker 4 vs earlier variations.

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kilotanker22

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So for many years I have had a RCBS Rock Chucker that was passed to me from a friend when I first started to load my own ammunition. It is one of the older ones. Only say "RC" on the side and has the older bicycle handle bar looking handle. Also it did not have a Bushing where the die threads through the press frame. Not could you switch which side the handle was on.

I have been looking for a new press lately and comparing a couple I found locally to my Rock Chucker. Today I picked up the newest variation of the Rock Chucker. Says Rock Chucker Supreme on the box and "RC IV" on the press frame.

I can say that this press is definitely larger. I noticed the height difference right away when pulling it out of the box. I also noticed that the ram seemed to be larger diameter. I measured with my caliper and the newer press has a 1" diameter ram. The older ram measures right between 7/8 and 15/16.

The ram on the newer press has a lot less play when at the top of the stroke. Presumably, because the older press has loaded tens of thousands of rounds.

Might be old news to some I guess, but I thought that I would share what I learned today. Overall this press seems to be well worth the $175 I paid at the local shop.

Now I wonder if the Hornady and Lee bushing systems will thread in the top if I were to remove the bushings. I would probably never do that, but I am betting they are the same threads.
 
Both the Lee Breach Lock adapter Hornady's L-N-L adapter will fit the Rockchucker Supreme. I have two complaints regarding the Supreme's design.

First, the spent primer catcher misses too many spent primers. I've eliminated this problem by depriming cases on a different press. Secondly, and more important to me, the ram is too tall for the frame opening such that you cannot see the clearance between the top of a shellholder and bottom of a die. I like to be able to see how much die clearance I have when setting up certain dies.
 
BBarn said:
Both the Lee Breach Lock adapter Hornady's L-N-L adapter will fit the Rockchucker Supreme. I have two complaints regarding the Supreme's design.

First, the spent primer catcher misses too many spent primers. I've eliminated this problem by depriming cases on a different press. Secondly, and more important to me, the ram is too tall for the frame opening such that you cannot see the clearance between the top of a shellholder and bottom of a die. I like to be able to see how much die clearance I have when setting up certain dies.
Click to expand...
Makes sense. I set it up and sized 100 cases last night and it did not miss A single primer.
 
I deprime then clean cases before lubing and resizing them. That keeps powder and primer residue out of the press body around the ram. Periodic cleaning and lubrication of the ram and its guide prevents wear and sloppy fit.

My two Rockcrusher presses bought in 1980 have less than .003" ram end play at the top of their stroke. Same as when new. My 1966 RCBS Jr. Press had .006" ram end play when new, now about .010".

RCBS shellholders have enough case rim and groove clearance to allow them to center perfectly in dies locked tight possibly not perfectly centered in the press threads.
 
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so what did they change on the RC 4 as far as the primer catcher? Can't find a close up pic online, RCBS website only shows the Supreme.

Can you post a pic and would it fit on a Supreme?

never mind just pulled mine out from the cabinet and it is a IV. I agree with BBarn on the primers. I just do everything on my Lee turret these days
 
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hounddawg said:
so what did they change on the RC 4 as far as the primer catcher? Can't find a close up pic online, RCBS website only shows the Supreme.

Can you post a pic and would it fit on a Supreme?

never mind just pulled mine out from the cabinet and it is a IV. I agree with BBarn on the primers. I just do everything on my Lee turret these days
Click to expand...

Here is a close up for you. Is it possible that RCBS has changed the primer catcher slightly, because of the issue that many have had?
 

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In case you are wondering. I use white Lithium grease for all the moving parts. No particular reason, just that's what I have always done and it works pretty well.
 
Kilotanker the Hornady LNL bushing fits the Rockchucker. I switched mine to it and works very well. I only use it for 45/70 and some handgun loads when trying a new load out.
 
nope same primer catcher as mine. For me the catcher would not snug up to the ram and primers would jump out the sides. Yours seem to be nice and tight in that picture. I ended up gluing a pair of neodymium magnets onto the side of the catcher that would pull the sides up close to the ram. Worked pretty good after that. But I also had some jump out of the slot in the front of the ram, about 1 out of 10. That was a easy fix with a small piece of soda straw.

I might remount the RC as a spare press if/when I pick up a big bore rifle. I would not want to try and resize a 45-70 on a Lee.
 
The older Rock Chucker presses were made in USA. They were unbreakable. Then there was a time they were allegedly made outside USA - these as still strong, but not like the old one's. These days with you current President it is probably made in the USA again!.
 
I started reloading in January 2019. The RCBS Rock Chucker kit was suggested to me for a good start.
The press is solid, the scale is accurate and the Uniflow powder measure is unbelievable. I have a few different scales that I check the charge with. I've read that there are better but I don't see how they could improve it.

It's all good info from this site...thank you all so much.

Just to add, sorry if I'm going off topic OP. I'm going to start loading for .308. Can I use the small drum that came with my RCBS Uniflow or do I need the larger one.
 
Kram,

I just got a used Uniflow that had a large installed and came with a small drum but no adjusting screw. After watching this video I knew I needed a small screw. I called RCBS and told them I needed a small screw for my drum and they sent it for gratis. :) How cool is that?

The small drum easily handles 43.3 grains of Varget for my 308. Easily...

It's a long video but he shares some really good Uni-flow user tips.

https://www.youtube.com/watch?v=LzGaPv_3oWQ
 
Kram,

I just got a used Uniflow that had a large installed and came with a small drum but no adjusting screw. After watching this video I knew I needed a small screw. I called RCBS and told them I needed a small screw for my drum and they sent it for gratis. How cool is that?

The small drum easily handles 43.3 grains of Varget for my 308. Easily...

It's a long video but he shares some really good Uni-flow user tips.
Click to expand...

Thank you kindly. I've read good things about RCBS's customer service but I didn't know it was this good.
I was just getting ready to go out to the shop a see how my small drum did with Varget. I don't have to now :)
On to the video...
Thanks again
 
If you are having problems w/ any RCBS product, call the service number and explain. You may be surprised at the fix they will supply you with, all usually at no charge.

I just watched a youtube of a fellow getting a tour of the Lyman factory. The docent (employee) emphasized several times that all castings/parts are US made.
 
Last year I broke the decaper pin on one of my die sets. No one local had any replacements. I called RCBS and asked to purchase some. They just sent me a pack of five at no cost.
 
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