Fire formed brass & headspace...

B

bjm42

New member
Suspect headspace problem with FL sizing? Light primer strikes (click - no bang) & residue @ case neck. Light firing pin indent (1 in 15). Rifle is good.
Just purchased a Lee Collet Necksizing die & wonder IF SAFE to load fire-formed cases without bump-sizing back a bit (.002) ? I can't figure out how to necksize while still adjusting headspace.
223 Rem, Savage Axis, .75 groups, 60gr Sierra HP, 24.6 Varget, CCI 450 (mag) primer.
Why light primer strikes?Maybe primer too hard, should change to CCI 400 or BR4?
Having brain fog on this, so will appreciate advice. Thanks :)
 
SameOle said:
Sounds like you are not seating the primers deep enough.
Click to expand...
Primers set @ .005.
At this point, I will try a primer switch, to eliminate the light strikes.
I was looking @ a very slight indent on primer, which made me suspect too much headspace.
Maybe my FL die got bumped around during last batch of 200 ? I just reset & tightened.
This is really one of my "feeling stupid" moments. Will load up again & head to range.
Thanks :)
 
Why do you say it’s not the rifle ? Is it only your reloads that fail to fire and factory ammo works fine in the rifle ?
 
bjm42 said:
Primers set @ .005.
At this point, I will try a primer switch, to eliminate the light strikes.
I was looking @ a very slight indent on primer, which made me suspect too much headspace.
Maybe my FL die got bumped around during last batch of 200 ? I just reset & tightened.
This is really one of my "feeling stupid" moments. Will load up again & head to range.
Thanks :)
Click to expand...
Forget the .005 seating depth bull droppings ....seat the primers all the way into the bottom of the primer pocket ... seat then until they will go in NO deeper !
If they are not bottomed out , the first impact of the firing pin only moves the primer farther into the case giving you that incorrect excuse of " Light Firing Pin strike "...
that's no correct ...the problem is the primer isn't seated all the way into the bottom of the pocket . Trust me on this !

Also ...not every primer pocket is the exact same depth ...they vary more than you think...measure a few thousand and see .
Gary
 
Reset FL die for .002 bump. Will try standard (not magnum) primers, set down firm in pockets.
Appreciate advice.
 
No probs with factory ammo; just not as accurate as my handloads.
I reset FL die & will try different primer.
 
The CCI 450s do have a thicker cup than the 400s. The easiest primer to light is going to be a Federal 205 or 205M.

Do you have a means of measuring head-to-shoulder length? If not, you can improvise with a spacer that accepts the neck and about half the shoulder and then put your caliper over from the case head to the top of the spacer to get a measurement. This is a relative measurement, and all that counts is the difference in before and after resizing length and not the absolute values of the numbers.

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Brass springs back slightly after fire-forming in the chamber, and unless you got an off-bore-axis chamber or bolt face, the cases will rechamber because of that springback. If you use the Lee collet neck sizing die on fireformed brass, you can shoot it in the Axis without other resizing. This is called neck-sizing-only and is a common practice. Depending on the pressure you are loading to, in a bolt-action rifle with a square bolt face and a chamber that is coaxial with the bore, you can do this several times before the case starts to get too snug to chamber (which may never happen if your loads are modest). This method just isn't reliable in ARs and Mini-14s and other self-loaders, for which the case needs at least two or three-thousandths of shoulder position reduction and a little narrowing to feed reliably.

If your chamber is set up long (something you can have tightened on the axis by loosening the barrel nut and turning the barrel in further), then you can over-resize and spend too much firing pin energy moving the whole case forward. Usually, that does not happen before the primer starts to light up, but in a cartridge as light as the .223, it may, depending how strong the striker spring is.
 
Copy that, Uncle Nick. My head is more clear for next step; Will load up comparison rounds with FL vs neck sizing only. Also purchased some Fed 205s.
Will follow with range report. Thanks :)
 
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