Primer seating question

To learn and introduce new loaders. Tips and tricks from old timers.

Moderators: Coordinators, Moderators

Primer seating question

Postby rimfireOH » Wed Mar 28, 2018 2:49 pm

I'm starting to load .455 Webley Mark II rounds, using once-fired Fiocchi casings and CCI's #500 small pistol primers. I'm using Lee's "auto prime" manual primer.

I noticed that the CCI primers seem to seat a little more easily than the same primers into 9mm Luger (for example).

As an experiment, I took a casing, primed it, put on hearing protection, loaded it into the firearm, pointed it downrange and pulled the trigger. It went "bang" (as expected) and when I removed the casing from the revolver, I noticed that the primer had unseated itself. Not enough to come all the way out, but enough that it was noticeable.

Should I be concerned? Am I using the wrong primers for this Fiocchi brass? If so, what should I be using?
If the pressure from just the primer is enough to do that, what's going to happen if I actually load it with a starting load of powder and add an actual projectile?
User avatar
rimfireOH
OFCC Member
OFCC Member
 
Posts: 347
Joined: Fri Dec 27, 2013 9:49 am
Location: NE Ohio

Re: Primer seating question

Postby evan price » Wed Mar 28, 2018 7:00 pm

Without a main charge to force the case head back against the breech it is common for primers to back out die to pressure in the primer pocket. People who use primer powered rounds often ream the flash hole oversized.
Some brass, especially foreign brass like ppu or fiocchi, have tighter primer pocket and some primers fit better.
"20% accurate as usual, Morty."

Striking down evil with the mighty sword of teamwork and the hammer of not bickering!
Carpe Noctem- we get more done after 2 am than most people do all day.
User avatar
evan price
Forum Janitor
Forum Janitor
 
Posts: 8819
Joined: Sun Jul 02, 2006 9:23 pm
Location: Westfield, Ohio

Re: Primer seating question

Postby rimfireOH » Thu Mar 29, 2018 4:08 am

Evan price: Thank you — your explanation makes total sense.
User avatar
rimfireOH
OFCC Member
OFCC Member
 
Posts: 347
Joined: Fri Dec 27, 2013 9:49 am
Location: NE Ohio

Re: Primer seating question

Postby rimfireOH » Fri Mar 30, 2018 3:06 pm

evan price: all of my handloads fired marvelously yesterday and none of their primers came unseated. Thanks for clarifying!
User avatar
rimfireOH
OFCC Member
OFCC Member
 
Posts: 347
Joined: Fri Dec 27, 2013 9:49 am
Location: NE Ohio

Re: Primer seating question

Postby evan price » Fri Mar 30, 2018 5:28 pm

Great work. Welcome to a hobby that will supposedly save you money......ha ha a he a. Seriously though.
"20% accurate as usual, Morty."

Striking down evil with the mighty sword of teamwork and the hammer of not bickering!
Carpe Noctem- we get more done after 2 am than most people do all day.
User avatar
evan price
Forum Janitor
Forum Janitor
 
Posts: 8819
Joined: Sun Jul 02, 2006 9:23 pm
Location: Westfield, Ohio

Re: Primer seating question

Postby willbird » Mon Apr 02, 2018 9:47 am

Actually during the firing process every primer may back out just like you saw, then building pressure forces the case back onto the primer early in the process.

Guns with excessive headpace may look like they have "flattened primers" even if pressures are not overly high.

Another example....most 45 acp brass is quite short if you measure them and compare the case length to the chamber depth, this makes a lot of fired 45 acp primers look strange even though the pressure is quite sedate. The primer IMHO rivets a bit while the case is being forced back onto it.

Bill
Have a great day today unless you have made other plans :-).
willbird
OFCC Member
OFCC Member
 
Posts: 11304
Joined: Tue Nov 08, 2005 9:19 am
Location: Exit 13 on the ohio Turnpike :-)

Re: Primer seating question

Postby jeep45238 » Mon Apr 02, 2018 9:50 am

evan price wrote:Great work. Welcome to a hobby that will supposedly save you money......ha ha a he a. Seriously though.


I got into it to save money......wound up spending the same amount of money, and shooting 85% more.
Never settle for the ordinary.

Rights cease to exist when restrictions are put on them.
User avatar
jeep45238
 
Posts: 5524
Joined: Sun Feb 18, 2007 10:29 am
Location: SW Ohio


Return to Handloading

Who is online

Users browsing this forum: Google [Bot] and 2 guests