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trim length

Checked trim length measurements on my once fired brass on the 6.5 x 284 and book trim length is 2.160 and more than half are 2.152 and shortest is 2.150 so I trimmed all of them at 2.150. I don't think there will be an issue with that, would it?
 
I wish more folks would make logical deductions like this. Too many look at numbers in the loading manuals and get stuck on whether it is black or white and they totally miss the gray. Those bullets are not going to miss that .010".

Steve :)

As a new reloader, I appreciate where the OP is coming from. You have safety safety safety, consistency consistency consistency beat into your head in all these reloading books and around the forums, without really understanding completely the relationship everything has with each other. Only thing you can do is ask around to people that know more than you to get confirmation that you're not ruining a few hundo of new brass.
 
I learned about the Sinclair bullet seating measuring tool on this site. Trimming to book specifications became unimportant after finding how long my chambers were. I may never have to trim for purposes other than uniformity.
 
Checked trim length measurements on my once fired brass on the 6.5 x 284 and book trim length is 2.160 and more than half are 2.152 and shortest is 2.150 so I trimmed all of them at 2.150. I don't think there will be an issue with that, would it?
As long as they are short shoot them .
Stay on top of the carbon ring. Larry
 
First of all, if by carbon ring you mean that bit of powder fouling that, lacking proper cleaning method can accumulate in the corner at the very front of the neck part of the chamber, why not solve that problem by catching it when you clean? Also, for those that have bore scopes, and have observed this phenomenon, can we agree that it only extends so far down the neck of the chamber, and may I propose that if your necks do not extend into that area, that there will be no interference?

Some time back, I viewed (on Youtube)six segments of a presentation that Jack Neary (a top level benchrest competitor who has been a member of the USA World Benchrest Championship team). One of the things that he discussed was trim length. Cutting to the chase, his chamber reamer is ground for a max. case length of 1.525" and his trim length is 1.490", a difference of .035". He shoots better than you or I, probably a lot better. So much for the accuracy aspect of end of neck gap. He also speaks quite favorably of trimming often...very often, based on his experience with how this favorably affects accuracy. Back in the day when I put together my first rifle for shooting groups at the range, a tight necked .222, I was careful to trim to .005 under book max. My fired brass would show shiny spots around the case mouth that seemed to indicate that at some point in the process of firing that it had made contact with the end of the chamber. At the time, I didn't give it much thought, since I just "knew" that having less clearance had to be better. Evidently I was wrong. I say that because instead of my own surmise and assumption, I have actual information from a highly qualified source. One of the great things about this hobby is that we get to learn something new every once in a while.
 
Checked trim length measurements on my once fired brass on the 6.5 x 284 and book trim length is 2.160 and more than half are 2.152 and shortest is 2.150 so I trimmed all of them at 2.150. I don't think there will be an issue with that, would it?

The SAAMI Minimum Case Length for 284 Win is 2.150, Trim To Length is 2.160. Trimming even shorter than Minimum would have no deleterious effect on function or safety, but you would be losing valuable neck length which may well preclude you from seating short / light bullets near the lands, nothing more.

To illustrate how uncritical Minimum Case Length is, Nosler's so-called "premium" 223 Rem cases come beautifully trimmed and finished a full .005" shorter than SAAMI Minimum. Q.E.D.
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Well, with a long range capacity cartridge (not a tiny little point blank 6PPC) the first thing you'll likely notice from excessive end clearance is heavier sooting of necks, possibly all the way down onto shoulders(depending on powder speed and neck clearance). Take these cases and set em next to a good chrono printout, and see if it doesn't mean more than 'making them all the same' did for you.
 
Checked trim length measurements on my once fired brass on the 6.5 x 284 and book trim length is 2.160 and more than half are 2.152 and shortest is 2.150 so I trimmed all of them at 2.150. I don't think there will be an issue with that, would it?
The only issue I could find is you trimmed them and then asked the question. I'd do that backwards if I had to ask a question next time.
 
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The difference between the capacity of a BR and a PPC is not much, particularly when you consider the difference in how much of the neck is filled with the bullet, the longer heavier BTs typically used for long range competition, compared to typical short range FB bullets more commonly used for short range work. I presume that you would consider the 6BR as qualified for long range work. Just because I generally shoot at short ranges, with the most accurate rifle that I own does not mean that I lack experience shooting and loading for larger cases.
 
Trimming too short increases the rate of throat erosion according to a former Army sniper who wrote a book about precision rifle.
 
Because if you did it wrong, you couldn't go back. Nothing personal, but I think I'd ask before cutting the brass to make sure I'm right. Sorry if this offended you.
No offense at all, I got thick skin. I knew that routine when shooters have several brass in variation lengths, most of them choose to cut to the smallest one of the bunch. It was just a question to start a thread to gather opinions from those with experience and knowledge.
 

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