RCBS reloading dies

[Jaygentry]

I'm having issues with my .223 RCBS does. I've been reloading for several years, not an expert, but know the process. Had a buddy of mine try to help, but still having issues. When I go to seat the bullet, the bullet will "crimp in" but if I put my thumb on the projectile, it will push down. It is almost as if it is crimping the top ring but not the rest. Any suggestions on this? I have 2 sets of dies doing the same thing. Do I send them to RCBS? I'm leaning toward me doing something wrong. Please help.

 

[billybob44]

For the most part do NOT crimp..

Believe it or not when you crimp (Over crimp) you are actually removing some of the case neck tension that is applied with your size die.
Yes, most of us believe that a crimp (on the cannalure) will help tighten the projectile..It does to a point, but with VERY small differences in OAL, some will be overcrimped, and this will loosen the case neck tension.

For ME, I use the RCBS TC die set. I think?? that this set also has a small base sizer.
I KNOW that I adjust the TC seater/crimp die to just "Kiss" the case mouth of sized and trimmed cases.
I can seat into the length of the cannalure, and get a good taper crimp with this set up with NO projectile push-back.

AGAIN, this is just MY method...Others will disagree...Bil

PS: I do NOT seat the projectile and crimp in the same step--Seat all first, and then back off of the seater stem and then crimp all...

PPS: Do NOT attempt a crimp at all if you do not have a cannalure on your chosen projectile..

 

[BR8818]

Have you measured the neck tension maybe a problem with the sizing die. If your neck tension is good then what Billy Bob said.

 

[billybob44]

https://www.midwayusa.com/product/1011284542
^^^This is the die set that I use==It works for me..Bill.

 

[Backpacker]

What is the measured diameter of the bullet? Measure it in 3 places rotating it about 120 degrees each time.

 

[bigedp51]

As stated by billtbob44 he has a set of RCBS AR Series .223/5.56 dies with a "TAPER CRIMP" that only slightly closes up the case mouth.

Below is the Lyman expander die I use for my AR15 and bolt action .223 rifles. It gives you .003 bullet grip and the .226 section of the expander allows the bullet to be started into the case with your fingers. This allows straight inline seating and no bullet tilt during seating, meaning reducing bullet runout. Then the taper crimp allow the case mouth to be closed slightly for streamlined bullet feeding. Bottom line, by reducing the expander diameter you increase bullet grip and eliminate the need for a roll crimp. And as stated above over crimping can actually reduce the bullet grip the case neck has on the bullet

Below a 9mm cartridge "before" applying a taper crimp, you can see the straight edge is resting on the belled case mouth.

Below the same cartridge after applying a slight taper crimp, this streamlines the case mouth for feeding and is not used for additional bullet grip. And when sized properly these pistol bullets do not move during feeding and firing of the pistol. And you can do the same with a AR15 without any type crimp at all.

NOTE, Whidden custom dies sells expander kits with five expanders from bullet diameter to .004 under bullet diameter to control the amount of bullet grip.

So again you do not have to roll crimp the case mouth to increase the case grip on the bullet. All you need to do is decrease the expander diameter and this will grip the bullet tighter.

Trust me, I have a few .223 reloading dies that I tested for bullet runout, and many of the rounds fired in my AR15 rifles did not have any crimp at all. I settled on the Lyman type "M" expander and a very slight taper crimp for my AR15 rifles.

 

[billybob44]

Plus 100 to bigedp51

^^^This guy has GREAT info here.
I especially like/use the Lyman 'M' Die for my flat base bullet loads for the .223 and others..Bill.

 

[Robert Richardson]

Could be the brass springing back. Check neck tension before you crimp.it.

 

[jcj54]

Expander ball could be oversize.
That was the issue with one of my die sets.