Datum line/bump

[Blacklab]

I know every rifle is different. Can I get an a number that I should be looking at for shoulder bumping. 1.200, 1.208, or 1.215 I was using the 375 Hornady gauge. Now knowing I needed the 350 gauge Can anybody help me w/ my new developed migraine. Thank you.

[dmsims21]

IIRC, others recommend only bumping the shoulder back 0.004"

I use a Wilson Case Gage

http://www.midwayusa.com/product/277624/le-wilson-case-length-headspace-gage-65-grendel?cm_vc=ProductFinding

I end up setting the shoulder back 0.005 to 0.006 so that is just passes the gage check. I don't want to have to worry about keeping ammo specific to one rifle.

[Blacklab]

Well this is what I'm doing. Once fired Hornady brass pre measured @ 1.215 - 1.216. After bumping 1.210 average I think I'm on track. Range time will be deciding factor.........lol