My brass does not fit chamber

Hirschi1

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Okay, so better than a year ago I bought used 6.5x284 norma brass (for a build that is finished now). It was fired in a 284 Win chamber once. So I full length sized it in a 6.5x284 norma die. It will chamber but with effort. Any suggestions? This is a new chamber, and I have new lapua brass that will chamber with ease.
Steve
 
that new rifle probably has a tight chamber and it is best to use new brass . seems hard to get the case body down to case head diameter with brass fired in a larger chamber.
 
Less than a handful of places brass can interfere with a chamber. 10 seconds and a sharpied case will tell you where it's at.
 
What brand of dies? Did you check the case length to make sure it is not too long?
You say they do chamber, but they require some "effort". How about loading one or two with a moderate load, and shoot them in your rifle. Maybe firing them in your chamber will help. Could be they were fired in a sloppy chamber, and your custom chamber is a little tighter.
 
Near The base of the case is where it is expanded too much. I trimmed the cases to length and prepped them.
 
1, try a Redding body die. May take a while to get, but it will work and can be used to bump the shoulder.
 
The original chamber it was fired in was larger than your current chamber so you need a small base die to get it down, common issue and easily avoided!
 
Compare the case head to shoulder datum length of the once fired, re-sized brass to that of the new Lapua brass. If the brass once fired in somebody else's 284 Win. chamber and full length re-sized per the setup instructions of most manufacturers' dies is longer from its head to shoulder datum than is the new Lapua brass what also chambered fine, then your chamber from bolt face to the chamber's shoulder is shorter than what your shellholder and 6.5/.284 Win. FL die combination is capable of producing, assuming there was maximum insertion of the case into the FL die with it adjusted to contact the shellholder plus another fraction of a turn, as per the typical manufacturer's instruction.

If not, adjust the die down to contact the shellholder plus just enough more of a fraction of a turn to cause the press to cam-over with full extension of the press ram. If the case still ends up too long from head to shoulder datum, then load up and shoot some of that new Lapua brass, re-size it, and try 'em for fit in your chamber.

If after firing and resizing the Lapua brass, it's also too long from head to shoulder datum, then either take off what you need from the topside of an inexpensive shellholder, or from the more expensive and hardened bottom surface of the die. "What you need" is at least the difference in head to shoulder datum length of the old brass vs. new, unfired Lapua plus another couple or three thousandths more as insurance.

If the problem has nutin to do with headspace, then you gotta find where there IS interference to chambering.
 
"Compare the case head to shoulder datum length of the once fired, re-sized brass to that of the new Lapua brass."

If you can measure the headspace on a Lapua case you can size the brass to fit the chamber. Measure something fired in the rifle and use about 1/1000" less than that length.
 
I can't measure accurately from head to shoulder. I would need to take it to the Smith. I plan on taking the rifle and things to him next week. I measured the cases though. The lapua unfired case at the bottom of the body measures .4985 and total case length is 2.166. The norma case that went through my full length sizer measured at the bottom of the body is .500 and the total case length is 2.159.
 
A full length sizer won't get it back down because when it was fired in the original chamber that spring back is larger than your chamber so when you full length size the spring back is to much for your chamber so you have to use a small base die to size it far enough that the spring back after sizing is inside the size of your chamber. Or polish out your new chamber to fit the once fired brass.
 
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Okay in the picture you can see slight marks on the body by the pen point and bullet tip. That is where pressure point are. This is a loaded round full length sized with the same die. It will not chamber at all. It measures at the base .500 also.
 

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