I sized and trimmed some Hornady .223 brass a couple of weeks ago and loaded 30 of the 50. I left the other 20 for about two weeks before getting back to them. The original trim length was 1.751. When I checked the length again, they ranged anywhere from 1.753 to 1.755. Still within tolerance but not what I originally trimmed. Can brass spring back longitudinally? I’ve only been reloading for a year and still use Lee Precision dies, with the mandrel type expander. Planning to upgrade to a FL bushing die during my stay at home.
Sized brass seems to get longer
- Thread starter Old Tanker
- Start date
Are proud primers giving you false readings?
Possible issues:
1. Measuring caliper is not repeatable or there is variation in your measurement technique i.e. centering the case, apply enough and consistent pressure to the moveable arm of the caliber case to case.
2. As KY-Windage said, a high primer will give you a false reading.
3. If you sized the case after taking the initial measurement the length can grow if you are not contacting / pushing the shoulder back - it's possible that you extruded the case which could lengthen it.
1. Measuring caliper is not repeatable or there is variation in your measurement technique i.e. centering the case, apply enough and consistent pressure to the moveable arm of the caliber case to case.
2. As KY-Windage said, a high primer will give you a false reading.
3. If you sized the case after taking the initial measurement the length can grow if you are not contacting / pushing the shoulder back - it's possible that you extruded the case which could lengthen it.
Trimmed after sizing.
I uniformed the pockets and all primers are seated at -.002 to .003
Okay, sounds like you know how to measure, so let me just say this. I was once trying to size my shoulders right up to the chamber shoulder. Not trusting measuring tools entirely, I loaded several of the loaded rounds in the rifle. Everything was fine, and the bolt closed easily or with only slight resistance.
But then a week or two later when I shot those rounds, the bolt was hard to close on every one of them. When I got back home and measured some of them, they were all .002 - .004 longer at the shoulder than they had been.
The only explanation I could think of was that the cases had indeed sprung back while they sat in the box waiting to get shot.
But then a week or two later when I shot those rounds, the bolt was hard to close on every one of them. When I got back home and measured some of them, they were all .002 - .004 longer at the shoulder than they had been.
The only explanation I could think of was that the cases had indeed sprung back while they sat in the box waiting to get shot.
Wow - that's interesting - didn't know that was possible - never encountered that before but will make a mental note about it.
I w/n/h thot it possible either but I measured every both before and after.
How many times fired are the cases?
that's pretty much how I understood the first three words of your post
to mean, as opposed to "I trimmed and sized some...". Seemed pretty clear to me but let's see how it goes now.
You're correct about the sizer button pulling the necks. If there is much force required to lower the ram back down as the button sizes the neck, you're pulling the shoulder forward. This is why it's so important to lube the INSIDE of the necks, but only with a FL die that has an expander. With a bushing die, no worries. Same with a neck sizer only that uses a mandrel like the Lee.
I do not FL size my 223 brass for bolt action use. If after several cycles I begin to get a "click" at the top of bolt opening, I'll FL size and anneal. Otherwise I use the Lee neck sizer most of the time. Runout near zero.
I'm shooting 73 Bergers and 69 Lapua's in LC brass, Criterion Match barrel, non competition only. Groups in the low 2's when the weather is just right. 100yds and 200m.
I do not FL size my 223 brass for bolt action use. If after several cycles I begin to get a "click" at the top of bolt opening, I'll FL size and anneal. Otherwise I use the Lee neck sizer most of the time. Runout near zero.
I'm shooting 73 Bergers and 69 Lapua's in LC brass, Criterion Match barrel, non competition only. Groups in the low 2's when the weather is just right. 100yds and 200m.
This is typical and nothing to worry about. This is also why you can't just neck size. Cases will stretch at the shoulder junction and also in length. Make sure you're not bumping shoulder more than two thousands. That expander in your sizing die will account for some of that stretch but usually after 4-5 firings they may need to be trimmed depending on how much trimming you did in your first cut. I trim my match brass .005" under my chamber length. I don't go by a reloading manual to tell me that. I use a chamber length measuring guage or my blueprint for the chamber. Going to a bushing die will help some if your use the blind expander. You can cut .010" under your chamber length but if you do it will increase forming of the carbon ring! Clean that carbon ring and bore after each shooting session! Know your chamber length don't guess.
New Hornady, just put them into service. That’s why I didn’t try to bump the brass. Just wanted to make sure the necks were round. Interestingly, the Hornady brass measures the same in headspace as my fired, Remington brass. I am not shooting max loads because I’m a recreational shooter, not a competition shooter. Barrel life is important.
After reading multiple posts on the subject, I’m pretty anal about chamber ring and cleaning. As far as the brass length, I sized before trimming. Also measured headspace before and after. In past loads, I had experience pulling the shoulder when extracting the expander. That’s why I was extremely careful about it this time.
jonbearman
I live in new york state,how unfortunate !
When you size a case it has to push the shoulder back in most case's. I see this very often and I trim last because I have 3 graceys set up to do 22 cal, 6mm, 6,5 and 30 cal on the same machine. I tried to trim before sizing but realized my Gracey use's the shoulder to basically trim the neck length and if all shoulders are slightly different they trim to all different lengths. Trim last is always best.
I’m pretty sure that I will invest in a FL bushing die for both .223 and 6.5CM. Looking at the L.E. Wilson. Any suggestions?
Purely subjectively and unscientifically I've found Hornady cases to be 'harder' in the neck / shoulder area than others. I resorted to re-annealing new cases on one occasion, but still didn't like them and junked them after little use. No experience with this make in 223, but it's not one I like or choose.
Brass hardness / springback seems the only likely explanation for this degree of difference assuming you didn't initially misread the trimmed length / mis-set the trimmer and/or your calipers are reliable/consistent. If it had been a single thou' change, I'd have said possibly temperature difference - I get this is with my reloading room being small and facing into the prevailing winds also receiving afternoon/evening sunlight giving large temperature variations, but 0.004" change is well outside of any expansion / contraction effects on both case and caliper.
Brass hardness / springback seems the only likely explanation for this degree of difference assuming you didn't initially misread the trimmed length / mis-set the trimmer and/or your calipers are reliable/consistent. If it had been a single thou' change, I'd have said possibly temperature difference - I get this is with my reloading room being small and facing into the prevailing winds also receiving afternoon/evening sunlight giving large temperature variations, but 0.004" change is well outside of any expansion / contraction effects on both case and caliper.
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