Loading some 500 special loads with RCBS 500 mag/500 special for a friend and having issues with Corbon 500 special cases. As I uses the expander die, it is making bulges in the case as it travels downward. Have to go fairly deep in the case to allow proper belled case mouth for bullet insertion. I previously loaded him some regular 500 Magnum rounds without this problem. It almost seems the corbon brass is thicker thereby making the expander so tight that it's bulging the case. My friend didnt have his firearm with him when he picked up the ammo, so we're not sure the rounds will even chamber. He thinks I made a mistake loading them and is afraid they will blow up. Anyone else having this problem?
500 S&W special RCBS dies bulging cases
- Thread starter garbhead
- Start date
- Status
FROGO207
Member
Welcome to the High Road.
First a couple disclaimers. I use Lee 500 S&W dies and I have never loaded any Corbon cases that I could identify as such. AND I never reload ammo for another shooter for the very reason of disastrous problems with those reloads.
So your thought seems on track with why they bulged. The other reason for bulged cases is when crimping an extra long case with dies set up for a shorter case they are crushed down and produce a ring that will keep the round from chambering. This most often happens with bottle necked cases. I would have pulled one down and measured the wall thickness compared to other brands of brass before anything else. Then If different I would have done a water volume comparison and dropped the propellant charge if less case volume was noted. Lastly the workup of loads for the different case volume is a must to stay safe. If you insist on helping your friend I offer that you work with him and help him make his own reloads with your equipment. At least then he will be responsible for the propellant charge and seating depth (ultimately the pressure) of the ammo. Those that decline the offer usually are just using you to make cheap ammo and are the first to blame YOU when they have a problem from my limited experience.Who knows he may eventually get a setup of his own one day.
First a couple disclaimers. I use Lee 500 S&W dies and I have never loaded any Corbon cases that I could identify as such. AND I never reload ammo for another shooter for the very reason of disastrous problems with those reloads.
So your thought seems on track with why they bulged. The other reason for bulged cases is when crimping an extra long case with dies set up for a shorter case they are crushed down and produce a ring that will keep the round from chambering. This most often happens with bottle necked cases. I would have pulled one down and measured the wall thickness compared to other brands of brass before anything else. Then If different I would have done a water volume comparison and dropped the propellant charge if less case volume was noted. Lastly the workup of loads for the different case volume is a must to stay safe. If you insist on helping your friend I offer that you work with him and help him make his own reloads with your equipment. At least then he will be responsible for the propellant charge and seating depth (ultimately the pressure) of the ammo. Those that decline the offer usually are just using you to make cheap ammo and are the first to blame YOU when they have a problem from my limited experience.Who knows he may eventually get a setup of his own one day.
Thanks for the input...I started reloading in the 70's...don't make it a habit to reload for anyone but myself. I loaded 50 rounds for him...27 500Mag and 23 500 special...I hand weighed each charge...for safety's sake. The bulging happened during the expanding / bell mouth stage. The longer magnum cases didn't bulge, only the shorter Corbon cases. Interestingly some of the shorter "special" cases are headstamped 500 Mag, and some aren't. I used the same dies on all the loads...this is a real mystery. I bought these dies, but I think I'll buy a set of them in Lee...like you I've never had an issue with Lee dies. Measure with micrometer: Sized case OD .525 Bulge OD .550 expander OD .495 Trying to figure out how to post pics. Thanks again
Attachments
Last edited:
Reefinmike
Member
By your pics it appears that expander ball is way too long for 500 special cases. The case gets thicker the closer you are to the case head which is why you have the bulge. Those cases marked 500mag that are special length could very well be cut down 500 mag brass.
243winxb
Member
Case wall thickness - 500 Special
Looks like a brass problem. http://www.saami.org/PubResources/CC_Drawings/Pistol/500%20Special.pdf The case walls are too thick?? Bulge OD at .550" (measured over the bullet area of loaded rounds) is .020" over standard maximum of .530" SAAMI body diameter. New dies are not going to help, IMO. Using SAAMI standard, the reloads will not chanber??? But the question remains, how was factory ammo chambered and fired the first time?? Strange.
Looks like a brass problem. http://www.saami.org/PubResources/CC_Drawings/Pistol/500%20Special.pdf The case walls are too thick?? Bulge OD at .550" (measured over the bullet area of loaded rounds) is .020" over standard maximum of .530" SAAMI body diameter. New dies are not going to help, IMO. Using SAAMI standard, the reloads will not chanber??? But the question remains, how was factory ammo chambered and fired the first time?? Strange.
243winxb
Member
That would do it, if the case wall gets thicker deeper into the case. I dont like the mixed head stamp .
sugarmaker
Member
500 case web begins about where your bulge begins, unlike 357 etc. they have a very long web area. Try inserting the expander in a fired case and see where it stops
FROGO207
Member
I agree that the dies are probably not the problem but my expander button is a lot shorter on the Lee 500/500 SPL combo die set FWIW. The brass I have does have a lot longer/thicker web on the 500 S&W as opposed to the SPL cases. However I have never bothered to load the sixty odd 500 SPL cases I have collected so far though. I just download the regular MAG cases to the SPL levels.
To get the mouth to flare, the expander had to go that deep...notice the part that creates the flare. I have contacted Cor-Bon about this as I feel the brass is the problem, since the bulge didn't happen on the regular longer 500 Magnum cases. the expander doesn't need to be that long, I may cut it off where its only about 3/8" long , that way it will flare the case but not travel so deep. I plan to pull these rounds and resize the cases. The dies are labeled 500mag/500spec, but think I'll go to Lee or Hornady and see how long their expander is.
Last edited:
ArchAngelCD
Member.
I would not buy another set if expensive dies based on a problem with one type if brass. I highly doubt it's the dies that are the problem from what you said.
You can load light 500 Special loads in the 500 Magnum brass if he wants light loads. I also would not be buying dies to load for someone else. Let him donate the dies to you for loading his ammo. (which I would not do)
You can load light 500 Special loads in the 500 Magnum brass if he wants light loads. I also would not be buying dies to load for someone else. Let him donate the dies to you for loading his ammo. (which I would not do)
AABEN
Member
I think you need to re-gust your dies I have had that happen on 40 and some 223 redid my dies and that was all to it. Not all the brass is the same you might need to trim your brass for it will stretch.GOOD LUCK
- Status
Similar threads
