Optimal primer seating depth ??

Bratcher02

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Minuteman
Feb 16, 2018
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Elizabeth, IN
What is the best depth for seating the primer ? Seat to the anvil of the primer or compress the anvil some or compress the anvil till it bottoms out on cup of primer ? Or don’t even let the primer touch the bottom of primer pocket?
 
I havnt found that it really matters in my type of shooting. Constantly seating them is the key. I use the century 21 hand priming tool and seat them until they bottom out.
 
After running an OCW and posting the results I will then usually fine tune with seating depth adjustments of .0005" at a time. Once this is complete I will adjust primer depth by .0005" and repost results. Usually takes about 1200 rounds to settle on a load for my 6mm creed then I will rebarrel at 1500 or so rounds............................:oops:.........................just bottom the primer cup out and call it good. Most of mine end up around .005" below flush but that depends on the brass, just make sure they are below flush once bottomed out.
 
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Like STI said, bottom out. I thought was having problems with CCI primers awhile back so I contacted their customer service and they told me that the primers needed to be clear to the bottom of the primer pocket to function properly which on Lapua brass was slightly below flush. Turns out my problem was caused by tumbling media caught in the primer hole.
 
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After running an OCW and posting the results I will then usually fine tune with seating depth adjustments of .0005" at a time. Once this is complete I will adjust primer depth by .0005" and repost results. Usually takes about 1200 rounds to settle on a load for my 6mm creed then I will rebarrel at 1500 or so rounds............................:oops:.........................just bottom the primer cup out and call it good. Most of mine end up around .005" below flush but that depends on the brass, just make sure they are below flush once bottomed out.
Lol yeah that kind of what I’m trying to prevent what was messing me up was the talk of .004 to .005 depth but if i do that on most of my norma brass I’m still .008 from bottoming out the cup on my primers but have noticed my groups opening up so that why I was asking the question! Always used a hand primer till I bought The primal rights primer seater which I like but could never get so precise with primer depth till now ended up opening a whole bag of worms lol but thanks for the info everyone will check groups out with cup seated all the way down and see if the groups tighten up I think I had them seated to far from the bottom of the cup and making inconsistent ignition but will find out soon when the rain stops lol