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Pistol Caliber pressure signs?

CanSniper

Sergeant
Full Member
Minuteman
Jul 25, 2011
321
69
Colorado, Pawnee Grass Land
Been loading rifle for along time, and feel very comfortable reading pressure signs.
Now, getting started loading pistol (mostly 9mm). First thing I noticed in the loading manuals is that pistol loads are comparativly lower pressure than rifle.
Which makes me wonder if they will show pressure indications the same as rifle, such as flat primers or ejector swipe or brass flow.
Not trying to push the envelope to the ragged edge but would like to be prepared just incase.
So...what do I need to watch for?
 
The primers will flatten just like a rifle primer. I have never noticed brass flow or anything else when over the line. Primer pockets loosening is the big one. The only things I've pushed to the edge out of all the calibers I've loaded for were 10mm and 45 Colt. In those, when the primer flattened the pockets started loosening right after. I'm not an engineer or physicist, but I guesstimate I was probably at 45k PSI or just under when I started losing pockets on the first firing.
 
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I'd go with the manuals. Alliant gives pressure readings with their loads. Remember that the interior volume is so much less, that changing seating depth has a HUGE influence on pressures.
 
If the slide takes your eye out, you are running too much pressure. Back the load off.
 
No, absolutely not. Many pistol rounds operate at so much lower pressure ranges that the appearance of most of the "rifle" pressure signs should be telling you that you're already way past the red line. Primers will still flatten in many loads (as mentioned, due in part to the thinner, softer cups) but signs like ejector marks shouldn't be appearing. Stick to the loading manuals using pressure tested loads. Velocity is another pretty good indicator. If you're getting 1300 fps from your 185 JHPs in a 45 ACP and there's no pressure signs, you need to think about the fact that you're getting 200 fps more than any sane manufacturer can manage. That should tell you something.
 
I've seen flatened primers in handgun cartriges but I don't think looking at primers is always a reliable preasure indicator for handgun rounds. In IPSC I shoot Major 9. This is a normal 9 case loaded to make major (125 grain jhp at around 1400 fps) This is a common practice for 2011 race guns. Some people estimate it takes over 40,000 psi to make major with a 9mm case. CCI small pistol primers really don't look to bad in these cases. The cases on the other hand get hammered.

My thinking is the same as mentioned above. Shoot your loads over a chronograph. If your getting more velocity than you "should" be getting then you most likely have higher preasure as well.