The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Thread Tools Search this Thread
Old May 2, 2006, 04:36 PM   #1
Senior Member
Join Date: March 11, 2005
Location: austin
Posts: 735
Pressure signs...How flat is too flat

I assume some flattening of primers is to be expected as you get close to a max charge but there must be a point where you need to back off. I guess I'm not sure how flat is too flat.
kingudaroad is offline  
Old May 2, 2006, 05:21 PM   #2
Senior Member
Join Date: October 15, 2004
Posts: 934
It ain't an exact science and primers can differ, but it the primer is still radiused at the edge, you're probably OK. If the edge is square and semi sharp, you're at max. If the edge has developed a little rim from spreading out into the chamfer of the primer pocket, you're too hot.
Leftoverdj is offline  
Old May 3, 2006, 10:44 AM   #3
Senior Member
Join Date: March 13, 2005
Location: Pennsylvania
Posts: 559
I've not found that flat primers are a good pressure indicator. Some are softer than others. Cratering of the primer from the firing pin is a clue but that also depends on primer softness. If you work a load up from 10% under max to max, at some point in your reloading career you'll find the bolt difficult to open. That's a pretty confident sign that pressure was too high. Knock the rest of that load apart and drop to the lower charge. If not accurate, change powders and start all over. Sometimes, however, the bolt is seemingly tough to open but I can blame it on the resized case. This is in loads where I have already established accuracy and safety and I notice the problem. But I don't completely full-length resize - I set the shoulder back 0.002" and sometimes for whatever reason the case doesn't resize like it should (maybe used too often?). Lots of varibales to consider. Just use your head and any time something doesn't seem right, stop where you are and evaluate. If you are not comfortable with a situation, discard the load. Start over.
cdoc42 is offline  
Old May 3, 2006, 11:21 AM   #4
Junior member
Join Date: September 25, 2005
Posts: 1,372
Primer appearance alone is not a good indicator of pressure. It should be taken into account with other variables. For example, when reloading 45 ACP, waiting for a CCI primer to flatten out is extremely dangerous, while a Federal primer will flatten out before max pressures are reached.
918v is offline  

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -5. The time now is 12:52 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2016 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent:
Contact Us
Page generated in 0.05053 seconds with 7 queries