So here's my question/problem, I have a redding bushing that I have been using for a few years that belongs to a friend. I decided to order my own set and was measuring my new lapua brass to make sure I get the right ones. The loaded brass is .337 OD, the bushing is a .334. so I decide to check some empty brass and find that the OD is .331. After checking a large sample I measured the ID of the bushing and it was .330. I called my friend and he checked his and they were all .003 under what the stamped size. So what gives. How does this add up.
- Thread starter parker_chp
- Start date
.002 to .003" under the size of the neck ON A LOADED ROUND is close to where you want to be. But if his bushing has been working, just check and see what's marked on it.
That was a good link, Devildog. It is short and to the point and totally answers the OPs question.
It tried that on my Hornady brass and it made the IF too small. Loaded round was 336 , used .334 bushing and it sizes too small. Then tried 335, that worked.
You risk raising chamber pressures if your neck tensions are to tight. Simply subtract 0.001" from the cartridge that had the smallest average measurement. This will allow for a slight amount of spring back and create a proper press fit for the bullet. As per Redding!
You have come closest to answering my question diver160651. why does my brass measure consistent .331 when the bushing is .334. shouldn't the OD of the case neck be the same diameter as the ID of the bushing? by the recommendation of every where I've ever looked .337 - .003 =.334 this should leave me with .003 neck tension. The fired OD is .343 which means I'm sizing down .009 by the bushing but in reality it is .012.
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