Bullet Seating Depth using RCBS Micrometer

GuitarXM · March 12, 2009, 08:34 PM

I have 308 winchester cases...
I was wondering if anyone out there has successfully used the RCBS Precision Micrometer to determine bullet seating depth...

I am a new reloader, and I know that the bullet that comes with the Micrometer is different from a regular 308 bullet since the ogive is different.

Has anyone used the RCBS precision micrometer to determine seating depth?

**Unclenick** · March 13, 2009, 12:58 AM

I've tried, but never trusted the result. Went over to the Hornady Overall Gauge system (still Stoney Point when I got them). The problem is getting the tension setting on the bullet right. I was never satisfied that I could tell whether the bullet had jammed into the throat hard enough be stuck enough that it pulled part way back out on extraction?

In retrospect, I think the easiest thing is to make it moderately loose and push it into the chamber by hand. Use a cleaning rod on the bullet to push it back out so you don't alter its position in the case. Measure gently so as not to scew the bullet into the case.

30Cal · March 13, 2009, 03:22 PM

Same here. It's not a good tool for that purpose.

I take a bullet of my choice, seat it long in a sized case, and stuff it into the chamber with my thumb. If it sticks, it's in the rifling. If it falls out from gravity alone, it's not in the rifling. Seat deeper in 0.005" increments till it sticks, then measure in the case mic. It's a heck of a lot more repeatable than trying to use the RCBS dummy case/bullet.

March 12, 2009, 08:34 PM	#1
GuitarXM Member Join Date: February 4, 2009 Posts: 63	Bullet Seating Depth using RCBS Micrometer I have 308 winchester cases... I was wondering if anyone out there has successfully used the RCBS Precision Micrometer to determine bullet seating depth... I am a new reloader, and I know that the bullet that comes with the Micrometer is different from a regular 308 bullet since the ogive is different. Has anyone used the RCBS precision micrometer to determine seating depth?

March 13, 2009, 12:58 AM	#2
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	I've tried, but never trusted the result. Went over to the Hornady Overall Gauge system (still Stoney Point when I got them). The problem is getting the tension setting on the bullet right. I was never satisfied that I could tell whether the bullet had jammed into the throat hard enough be stuck enough that it pulled part way back out on extraction? In retrospect, I think the easiest thing is to make it moderately loose and push it into the chamber by hand. Use a cleaning rod on the bullet to push it back out so you don't alter its position in the case. Measure gently so as not to scew the bullet into the case. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

March 13, 2009, 03:22 PM	#3
30Cal Senior Member Join Date: December 3, 2002 Posts: 1,264	Same here. It's not a good tool for that purpose. I take a bullet of my choice, seat it long in a sized case, and stuff it into the chamber with my thumb. If it sticks, it's in the rifling. If it falls out from gravity alone, it's not in the rifling. Seat deeper in 0.005" increments till it sticks, then measure in the case mic. It's a heck of a lot more repeatable than trying to use the RCBS dummy case/bullet.