jrdavidson
Member
- Joined
- Apr 4, 2011
- Messages
- 22
First post by newbie reloader here. I could really use some advice on how to get consistent OAL measurements.
Here's my setup:
Redding T7 turret press
RCBS 9mm decapper/sizing die
RCBS expander die
Redding Competition Seating die
Redding taper crimp die
Rainier 115 gr RN plated bullets
I have segregated 1-time fired cases by headstamp, trying to rule out variations there.
Here's the problem:
I'm making up some trial rounds last night (no primer, no powder, just cases and bullets), taking them all the way through the press: decapper/sizer, adding slight bell flare (just enough to let the bullet start to seat), seating, and taper crimp.
I get a good seat and crimp - just enough to remove the flare and the slight wasp waist in 9mm that everyone says is fine. Everything *looks* great - but I want to confirm my OAL is what I'm looking for.
Here's my problem - using calipers on my assembled test round, I can't get a consistent measurement because the round keeps moving around in the caliper differently everytime I measure. The variance can be as much as +-.005 thousandths on the caliper. The guilty party is the RN nose.
On rifle rounds I see some people use the Hornady comparator setup with a case cage mounted to the caliper jaw to measure off the ogive of the bullet as opposed to the bullet tip - but these comparators are used only for rifle rounds for some reason. No 9mm setups.
So what's the secret to measuring OAL on a 9mm RN round using a caliper? I just can't get it to be consistent. Any tricks?
Thanks!
Here's my setup:
Redding T7 turret press
RCBS 9mm decapper/sizing die
RCBS expander die
Redding Competition Seating die
Redding taper crimp die
Rainier 115 gr RN plated bullets
I have segregated 1-time fired cases by headstamp, trying to rule out variations there.
Here's the problem:
I'm making up some trial rounds last night (no primer, no powder, just cases and bullets), taking them all the way through the press: decapper/sizer, adding slight bell flare (just enough to let the bullet start to seat), seating, and taper crimp.
I get a good seat and crimp - just enough to remove the flare and the slight wasp waist in 9mm that everyone says is fine. Everything *looks* great - but I want to confirm my OAL is what I'm looking for.
Here's my problem - using calipers on my assembled test round, I can't get a consistent measurement because the round keeps moving around in the caliper differently everytime I measure. The variance can be as much as +-.005 thousandths on the caliper. The guilty party is the RN nose.
On rifle rounds I see some people use the Hornady comparator setup with a case cage mounted to the caliper jaw to measure off the ogive of the bullet as opposed to the bullet tip - but these comparators are used only for rifle rounds for some reason. No 9mm setups.
So what's the secret to measuring OAL on a 9mm RN round using a caliper? I just can't get it to be consistent. Any tricks?
Thanks!