Page 1 of 1

Primer seating question

Posted: Wed Mar 28, 2018 2:49 pm
by rimfireOH
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?

Re: Primer seating question

Posted: Wed Mar 28, 2018 7:00 pm
by evan price
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.

Re: Primer seating question

Posted: Thu Mar 29, 2018 4:08 am
by rimfireOH
Evan price: Thank you — your explanation makes total sense.

Re: Primer seating question

Posted: Fri Mar 30, 2018 3:06 pm
by rimfireOH
evan price: all of my handloads fired marvelously yesterday and none of their primers came unseated. Thanks for clarifying!

Re: Primer seating question

Posted: Fri Mar 30, 2018 5:28 pm
by evan price
Great work. Welcome to a hobby that will supposedly save you money......ha ha a he a. Seriously though.

Re: Primer seating question

Posted: Mon Apr 02, 2018 9:47 am
by willbird
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

Re: Primer seating question

Posted: Mon Apr 02, 2018 9:50 am
by jeep45238
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.

Re: Primer seating question

Posted: Tue Apr 24, 2018 8:49 am
by cpg
Am I the only one that thinks the OP should be using a large pistol primer for .455 Webley?

Re: Primer seating question

Posted: Tue Apr 24, 2018 9:05 am
by JustaShooter
cpg wrote:Am I the only one that thinks the OP should be using a large pistol primer for .455 Webley?
Depends on the case - modern cases made by Fiocchi take small pistol primers. Older cases probably do take large pistol primers. It's pretty apparent if you try to use the wrong primer, one won't fit, the other falls out, so...

Re: Primer seating question

Posted: Tue Apr 24, 2018 9:10 am
by cpg
OK, thanks. I wasn't aware the Fiocchi brass was small primer. Learned something new today!!

Re: Primer seating question

Posted: Tue Apr 24, 2018 3:12 pm
by rimfireOH
Yep, it's new Fiocchi brass, so small pistol primers. Whew, for a moment I thought I'd been doing something wrong. (Well, I probably am, but it's something else, most likely.)

Re: Primer seating question

Posted: Tue Apr 24, 2018 7:15 pm
by true_pair
cpg wrote:OK, thanks. I wasn't aware the Fiocchi brass was small primer. Learned something new today!!
Federal also makes small pistol primer rounds in 45 ACP. So Fiocchi is not the only one out there making larger caliber brass with small pistol primers

Re: Primer seating question

Posted: Wed Apr 25, 2018 7:38 am
by willbird
true_pair wrote:
cpg wrote:OK, thanks. I wasn't aware the Fiocchi brass was small primer. Learned something new today!!
Federal also makes small pistol primer rounds in 45 ACP. So Fiocchi is not the only one out there making larger caliber brass with small pistol primers
Some of the lead free stuff uses small primers.It often has a larger than normal flash holes. It sometimes has the primer crimped in, and the federal stuff I have seen the primer is copper colored as well.

Bill

Re: Primer seating question

Posted: Thu May 03, 2018 11:52 pm
by Werz
true_pair wrote:
cpg wrote:OK, thanks. I wasn't aware the Fiocchi brass was small primer. Learned something new today!!
Federal also makes small pistol primer rounds in 45 ACP. So Fiocchi is not the only one out there making larger caliber brass with small pistol primers
I have to separate all my .45 ACP brass after tumbling. To be certain, I use a double-ended primer cup reamer, first trying the large end. Looking for the brand on the headstamp isn't effective, since CCI and Federal make brass in both sizes.