How To Shoulder Bump

fstdraw · Aug 22, 2022

May I chime in? I've been loading .223 for 15 years and NEVER have done anything to the cases but run the ram up until it cams over and that's it. Same with 762 Russian. All my decapping/sizing has been done using the RCBS single stage Jr's etc. I've not done anything that I know of to "bump back the shoulder". I use a case length gage all along the operation. Never had a problem with my ammo working in several different guns. I use both full length and small base dies.

Do I need to add a step?

Koda · Aug 22, 2022

fstdraw said:
Do I need to add a step?

Not if your getting the results that work for you. Im shoulder bumping because it minimizes working the brass extending its life and think theres supposed to be some accuracy or velocity improvement but cant say for sure on that part.

My threads been revived

I should add that shoulder bumping has been working great from me using the advice I got in this thread.

fstdraw · Aug 23, 2022

Thank you for that. I've not had accuracy issues and I get several loads per casing. Besides, I live in ignorance because I wouldn't know if I needed to bump or not.

Mikej · Aug 25, 2022

fstdraw said:
May I chime in? I've been loading .223 for 15 years and NEVER have done anything to the cases but run the ram up until it cams over and that's it. Same with 762 Russian. All my decapping/sizing has been done using the RCBS single stage Jr's etc. I've not done anything that I know of to "bump back the shoulder". I use a case length gage all along the operation. Never had a problem with my ammo working in several different guns. I use both full length and small base dies.

Do I need to add a step?

No, not if every thing works like it's supposed to. Heck, if your sized brass fits in one of those LE Wilson case gauges you're golden. The reason myself, and others I presume, mess around with "The Bump" is to attempt to lessen how much the brass is worked when bumping the shoulder back. And I imagine the "Accuracy" folks do it too. Using a comparator to see what factory ammo measures, and compare it to your fired ammo, gives you a range of how far to bump the shoulder. In my case, no pun intended, I found that I didn't need to bump for the 6.5 Swede bolt action. And in the Garands only needed to bump .002". Even though the factory ammo was .005" shorter.
In the 6.5 I backed the die off of the shell holder a little to only size the neck.