C.O.L. Tolerances

Bigbull

Junior Member
Joined
Oct 18, 2016
Messages
26
Location
Sutherlin, Oregon
I was wondering how precise you guys keep your C.O.L.? It seems a little difficult to get every cartridge the exact same length down to the thousandth, so I am curious what you guys do.

Bigbull
 

N2TRKYS

Senior Member
Joined
Apr 17, 2016
Messages
2,523
Location
Alabama
I haven't noticed enough of a difference in bullet length variances for it to matter in my loadings.
 

pods8

1
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Mar 12, 2014
Messages
3,087
Location
Thornton, CO
I base mine off the ogive as mentioned and that is what I keep in my notes. I set the dies up for that to start my reloading session and then I'm good to go (I check occasionally but it holds fine), I don't worry the tips vary slightly so COAL drifts slightly.
 

CareyJAF50

Senior Member
Joined
Jan 11, 2016
Messages
156
I had the sameeee problem chasing OALs all over the place until, just like these guys have said, a bullet comparator was introduced to my newb ass at the time. So much easier.
 
OP
B

Bigbull

Junior Member
Joined
Oct 18, 2016
Messages
26
Location
Sutherlin, Oregon
I had the sameeee problem chasing OALs all over the place until, just like these guys have said, a bullet comparator was introduced to my newb ass at the time. So much easier.

Hey thanks for the feedback on this guys. Looks like I will be getting a bullet comparator.


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HellsCanyon

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Joined
May 29, 2012
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3,474
Location
Lewiston ID
Even measuring off the Ogive you'll see variances of a thousandth here and there. From what I've seen and documented, proper annealing goes a long ways in having consistent neck tension and maintaining the elasticity of the brass. If you have a mix of cases where the necks have work hardened to varying degrees, they won't spring back like they should and you'll sometimes see it reflected in inconsistent seating depths (.002-.005" is what I've seen). Have had this happen on 300 and 338 Normas as well as a few 28 Noslers. Using proper bushing dies as well as annealing has all but eliminated the problem.

One other thing to mention as well is the bearing surfaces on some bullets will vary. I know of a 300 win mag shooter than has as much as .0015 difference in bearing surface, and he sorts them in .0005" increments, adjusts his powder charge accordingly and has significantly reduced his velocity ES.

Mike
 
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