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  #21  
Old 01-25-2019, 08:21 AM
rcolarco rcolarco is offline
 
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I'm trying to figure out what problem people are trying to solve by fiddling with base to shoulder dimensions on cases for gas guns. Accuracy? Case life? Seems like a lot of fiddling for nebulous gains, and the real potential for malfunctions at the wrong time.

I full-length resize. My ammunition is sufficiently accurate for anything I do. I pick up enough brass at the range that I will never lack.

Somebody tell me why.
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  #22  
Old 01-26-2019, 04:06 AM
HighpowerRifleBrony HighpowerRifleBrony is offline
 
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Yes. It's initial fiddling, then set and forget. I'm full length sizing, just not pushing the shoulder back unnecessarily



If you use enough lube, especially inside the neck, you can keep variation within 1 thou (well with 5.56, I haven't measured '06 yet). Aim for 2-3 thou under chamber and it's perfect. Four thou or more under chamber size starts showing primer flattening and case life decreases quickly.
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  #23  
Old 01-28-2019, 12:38 PM
Unclenick Unclenick is offline
 
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Primer flattening, in that instance, is due to the primer backing out further and inflating slightly before being reseated as the head stretches back. It's not a high-pressure sign. However, if that goes far enough and the corners flatten too severely, it can lead to edge piercing and garnering additional gas-cut pits in the bolt face.
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  #24  
Old 01-29-2019, 08:57 PM
HighpowerRifleBrony HighpowerRifleBrony is offline
 
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Yup.
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