Properly adjusting (RCBS) dies

[azar]

Okay,

So I have been reloading for nearly 2 1/2 years. I didn't consider myself a newbie at it anymore although I'm more than willing to admit that I have a long way to go before I match many of the experienced reloaders here at THR. But last night made me question myself a bit.

I had just received a package in the mail that, among other things, contained some Ballistol. I disassembled my RCBS Precision dies (standard green box) to give them a cleaning and rust protection using the Ballistol. A few things really caught my attention.

My 7mm Rem Mag FL resizing/exanding die did not have the expander rod centered in the die. If I took the lock ring off and did a "roll test" I could see wobble on the decapping pin. I realized that after purchasing these dies, I had never disassembled them for cleaning to remove the factory protectant and had never verified the expander rod assembly was centered in the die.

The second thing I noticed, as I was perusing the RCBS instruction sheet, is that I have been using the seater die all wrong all along! It says to place a sized, primed, and charged case into the shell holder and raise the ram. Then screw the die down until they make contact and back the die out (1/2 or 1 full turn, I can't recall now). Then to adjust the seater plug using the stem protruding from the top of the die to get the desired OAL. I may have done this on my first batch or two of reloads 2 1/2 years ago, but since then I have been loosening the lock ring and adjusting the die itself. :banghead:

How big of a deal is it that I was adjusting the die instead of the seater plug? Would that affect accuracy (more chance for bullet runout, etc)?

If my expander rod wasn't properly centered in the FL sizing die, that WOULD definitely cause accuracy issues, would it not? What is the best way to make sure that the expanding rod is properly centered? I simply adjusted it and then rolled it on the counter to see if I could see any wobble until it appeared okay.

If both of these things could affect the accuracy of the loaded rounds It would really explain a lot. The reloads from my 7mm Rem Mag have been around 1.5" at best and the worst around 4.2".

 

[243winxb]

How big of a deal is it that I was adjusting the die instead of the seater plug?

There is a crimper in the seating die. If the die is to far down, you will be crimping while seating the bullet.

What is the best way to make sure that the expanding rod is properly centered?

Adjust and tighten while the expander is inside the case.

 

[rcmodel]

To center the decapping rod:
Back it out, then size a case and leave it up in the die.

Now slowly screw the decapping pin down while feeling around for the flash hole in the case. Continue adjusting down until it knocks the primer out, then give it another 3/4 turn or so.

While leaving it in the flash hole, tighten the lock nut.

This will hold the rod centered in the flash hole and allow the threads on the stem and lock nut to self-center.

rc

 

[azar]

Thanks 243winxb and rcmodel, great advice!

Now, what should I do with all the ammo previously loaded with the misaligned dies? I probably have about 40 to 50 rounds loaded across 8 to 10 different loads.

 

[243winxb]

RCBS Seating Die adjustment, No Crimping, bottle neck case.

The factory instructions-

Screw the seater die into the press untill you feel it touch the mouth of the case. Back up th die 1/8 of a turn (never more) and set the large lock ring. This will leave a gap between the bottom of the die and shell holder about 1/16" or the thickness of a nickel. Seater Dies have a unique alignment device built into them which aligns the bullet with the case mouth an instant before seating

There are other tricks to help get more accurate bullet seating. Seating Die Adjustment
When using standard RCBS dies for bottle neck case like 243win. A few tricks might make a difference. 1. Use a feeler gauge or shim 1/16" thick. Run the ram/shell holder up. With shim/gage of 1/16" placed on top of shell holder. Screw die down on to gage. Set lock ring. This way the seating die is square and your not touching the crimper inside the die. 2. The 2nd method uses the crimper in the die to support the case neck at final seating. All your brass MUST be trimmed to the exact same length OR use the longest case of the lot when adjusting the die. Place the longest case of the lot into the ram/shell holder. Run it up all the way. Now with the bullet seating stem backed out, turn the die down till you feel the die/crimper kiss the case mouth. The dies crimper will just be resting on the case, NOT crimping. Set the lock ring at this time. This MAY square the shell holder with the die/case, dont know? But the case mouth is supported on the last few .001" 's of its travel as the bullet seats without crimping. The case mouth/neck will not have side to side movement. Does all this work? I like to hope so. Groups on paper say maybe. Read post #3 here also http://www.thehighroad.org/showthread.php?t=425776

Now, what should I do with all the ammo previously loaded with the misaligned dies?

I would shoot them, you dont know for sure that you did anything wrong. If you crimped to hard the rounds will not chamber. It the die was backed out to far you might have more runout than normal. If rounds chamber OK, shoot them.

 

[kelbro]

Loosen the nut on your decapping rod and put an o-ring between the nut and the die. Just snug it down. The decapping rod will self-center with a smooth steady press stroke.

Now, what should I do with all the ammo previously loaded with the misaligned dies? I probably have about 40 to 50 rounds loaded across 8 to 10 different loads.

Roll them across a mirror and see if they are reasonably concentric.

 

[azar]

Thanks Kelbro that's also a good idea. Do you know what size o-ring I need to buy?

Also, anyone have suggestions with the 40 or so rounds I have already made previously? Anyway to fix them if they were size with the expander rod crooked? Pull the bullets, back out the decapping pin so as not to knock out the live primer, resize, recharge and reassemble?