OAL variations, HELP

watsknew

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Hi all

I apologize if this has been covered on another thread i search and didn't really find what i was looking for. I'm new to reloading, just started the other day. I have a Redding Big Boss press, and Redding competition dies in .308. I think i've done everything right so far, but when i measure OAL from one round to the next there are rather large variations. 2.840 for the first and the next ones were 2.825 and in between. Is this normal? i measured the length of some of the bullets by themselves and they were off by as much as .010 as well. I'm using Nosler J4 competition 168 gr, i thought maybe the bullets were the culprit, i trimmed all the cases to the same length and all of that. Any help would be appreciated. Thanks
 
You need a Hornady OAL gauge. Simple to use, can be used with any bullet, measures to the lands. I picked one up from P&D Enterprises, works great. I'm sure they'll have a 308 case. If they don't, send them a fired case and they'll tap it to fit the tool for you.
 
If the Hornady OAL tool still uses the same threads as Stoney Point, the thread is 5/16"-36. These guys (http://www.victornet.com) sell the taps, so does MSC Direct.

Using a case that has been fired and formed in your own chamber will yield better results.
 
Use a comparator. I have found that measuring from the bullet tip to the shell base is hit or miss depending on how the jacket was swaged over the core. I have seen them out farther than the .010 you mentioned. Some are worse than others.

Varied neck friction while seating the bullet can effect OAL as well. I loaded some rounds up last night and had a few that I had to run through the seating die again as they were .005 farther out than the ones that weren't "sticky" going in.
 
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