almiz111 26 Posted April 8, 2015 After full sizing my 223 brass seems to be short, call it 1740 and up. Hardly ever have to trim. The main question - what is the lower limit? 1730? So is this bad and why? As usual other forums are confusuing. Any reference to previous posts?? Thanks. Quote Share this post Link to post Share on other sites
MidwestPX 172 Posted April 8, 2015 IIRC, spec is 1.750 +/-.001. I target 1.745 but typically get between 1.740 and 1.750 due to slop in the machine (I trim on my 1050 during the sizing operation). Short brass is better than long as if it's too long, it can crimp the bullet and cause a pressure spike. Quote Share this post Link to post Share on other sites
T Bill 649 Posted April 8, 2015 SAAMI lower trim to length is 1.730. Remington brass is one known to be short from the factory. I have gotten Remington once fires that measure 1.740. Don't worry it will grow after multiple firing. Short of finding out your chamber dimensions, I would not worry to much about it unless making precision rounds. 1.740 is my preferred length and I trim again when they creep up to 1.76. Over the years I have not seen much of a difference in accuracy. Quote Share this post Link to post Share on other sites
almiz111 26 Posted April 9, 2015 Thanks Gents. Appreciate it and I should have been smart enough to Google the references myself. Quote Share this post Link to post Share on other sites
tony357 386 Posted April 9, 2015 EZEE PZEE http://www.dillonprecision.com/#/content/p/9/pid/25547/catid/3/Dillon_Rifle_Case_Gages Quote Share this post Link to post Share on other sites
NJKen 23 Posted April 10, 2015 Most likely you have your dies set up perfectly. Ive found the 223 to stretch more when oversized (shoulder pushed back to far). Once I set my dies with a case gauge I found that I was pushing the shoulder back way too far. Once I set em rite case trimming was not needed most of the time. Hot loads causes em to stretch but moderate/plinking loads, not so bad. Ken Quote Share this post Link to post Share on other sites