High Primers - The Firearms Forum

312shooter · 10-20-2008, 01:46 AM

Does anyone know if there is ANY calibers or scenarios in which primers above flush are normal? I think I'm being fed some BS by a local guy on some reloading techniques as these "high primers" on 9mm sound dangerous as hell to me. I ALWAYS check primers for below flush I just wanted to consult the gurus on this story. Thanks guys!

Gene Seward · 10-20-2008, 05:47 AM

Never heard of such a thing around these woods. LOL Sounds dangerous, and like you would have feed problems. It is amazing what BS is out there. I myself try to get them as flush as possible.

Terry_P · 10-20-2008, 07:45 AM

Seat them flush as high primers can be a real issue. I've seen double BBL's double up because of a high primer. In a semi auto I think they call it a slam fire??

LDBennett · 10-20-2008, 07:55 AM

NO reloading manual EVER suggests anything for primer height other than below flush. Flush is not even good enough.

The primer has a small anvil inside it with legs that are designed to sit against the bottom of the primer pocket. When the firing pin strikes the back of the primer, it hits the anvil through the backside of the primer. If the primer is high then it has to first seat the anvils feet against the back of the primer pocket before any energy can be given to the primer compound. If it takes too much energy to seat the primer then there is not enough left for the priming compound to get ignited.

Then there is the safety aspect. If the primer is high it can rest on the bolt face which can act as a big firing pin as the bolt slams closed. This can result in what is called a "slam fire" and in semi-auto guns it is a NO-NO. Any reloading source of information will advise that all primers MUST be seated below the face of the back of the cartridges or slam fires MAY occur.

The only good source of reloading information is reloading manuals by large powder and bullet and reloading equipment manufacturers. Anything they print makes them liable so you can bet they researched and tested every recommendation in their manuals. The guy at the club or range who gives you a recommendation has no liabiltiy and can tell you anything he wants. He can take his own advice and suffer the consequences too. Don't be his guinea pig and take his advice. Stick to proven advice from an actual manufacture's reolading manual. BE SAFE!

LDBennett

Bindernut · 10-20-2008, 05:01 PM

Never heard of any cartridge using high primers as a "normal". Sounds dangerous and you're setting yourself up for slamfires...or even a discharge if you drop a round on the concrete beside you! I think the local know-it-all is full of wind on that one!

With clean primer pockets and good brass the primer should be seated slightly below flush.

artabr · 10-20-2008, 11:31 PM

Quote:

Originally Posted by Bindernut

Never heard of any cartridge using high primers as a "normal". Sounds dangerous and you're setting yourself up for slamfires...or even a discharge if you drop a round on the concrete beside you! I think the local know-it-all is full of wind on that one!

With clean primer pockets and good brass the primer should be seated slightly below flush.

Ditto to all of the above. Bindernut is dead on.
You don't want to even chamber a high primer. Let the slide go on that and you could easily have a slam fire.

Art

TranterUK · 10-21-2008, 03:00 AM

High primers would be very dangerous indeed, with the potential for detonation of the cartridge 'before' it chambered, sending bits of brass all over. And the unlikely but not unknown chain detonation of the rounds in the magazine!

Shellback · 10-21-2008, 05:09 AM

Quote:

Originally Posted by LDBennett

NO reloading manual EVER suggests anything for primer height other than below flush. Flush is not even good enough.

The primer has a small anvil inside it with legs that are designed to sit against the bottom of the primer pocket. When the firing pin strikes the back of the primer, it hits the anvil through the backside of the primer. If the primer is high then it has to first seat the anvils feet against the back of the primer pocket before any energy can be given to the primer compound. If it takes too much energy to seat the primer then there is not enough left for the priming compound to get ignited.

Then there is the safety aspect. If the primer is high it can rest on the bolt face which can act as a big firing pin as the bolt slams closed. This can result in what is called a "slam fire" and in semi-auto guns it is a NO-NO. Any reloading source of information will advise that all primers MUST be seated below the face of the back of the cartridges or slam fires MAY occur.

The only good source of reloading information is reloading manuals by large powder and bullet and reloading equipment manufacturers. Anything they print makes them liable so you can bet they researched and tested every recommendation in their manuals. The guy at the club or range who gives you a recommendation has no liabiltiy and can tell you anything he wants. He can take his own advice and suffer the consequences too. Don't be his guinea pig and take his advice. Stick to proven advice from an actual manufacture's reolading manual. BE SAFE!

LDBennett

LD your posts are very informative, you are a asset to this forum thank you. Again you are right in the 10 spot on this one, in no way ever should a primer be seated in that manner.
Tim

Dirtypacman · 10-21-2008, 01:34 PM

I have never heard of anyone reloading that looks to get anything but a flush primer. I have never read or heard anything positive about a High Primer.

LDBennett · 10-21-2008, 03:25 PM

Dirtypacman:

Not flush but below flush, but by only a thousandth or two.... you can just feel that it is below flush with your finger. My Dillon is designed so it only installs them one way: correctly and below flush.

LDBennett

mrkirker · 10-21-2008, 03:51 PM

Loading a tube-type mag with 'high primer' ammo is a Recipe for Disaster!

Don't even THINK of it!

312shooter · 10-21-2008, 10:22 PM

Thank guys, I didn't have any intentions in doing so as I have never seen data that suggested this was a good move. I was interested to know if there was such a theory in our universe of reloading.

Dirtypacman · 10-24-2008, 11:54 AM

Quote:

Originally Posted by LDBennett

Dirtypacman:

Not flush but below flush, but by only a thousandth or two.... you can just feel that it is below flush with your finger. My Dillon is designed so it only installs them one way: correctly and below flush.

LDBennett

Thanks LD - i also use a dillon and try to assure that is how they come out. I have had high primers cause problems before so I appreciate the clarification.

bobkk · 10-26-2008, 05:53 PM

Bought a Ruger 44 carbine years ago. Well known manual said to use
rifle primers if you were going to shoot them in a rifle. That didn't
work they wouldn't seat flush. Glad I caught that on the first case.
Primer pocket"s on pistol cases aren't as deep as rifle pockets.

10-20-2008, 01:46 AM	#1
312shooter Advanced Senior Member Join Date: Mar 2008 Location: Las Vegas NV Posts: 1,148	High Primers Does anyone know if there is ANY calibers or scenarios in which primers above flush are normal? I think I'm being fed some BS by a local guy on some reloading techniques as these "high primers" on 9mm sound dangerous as hell to me. I ALWAYS check primers for below flush I just wanted to consult the gurus on this story. Thanks guys! -->

10-20-2008, 05:47 AM	#2
Gene Seward V.I.P. Member Join Date: Mar 2007 Location: Batesville, Arkansas Posts: 477	Re: High Primers Never heard of such a thing around these woods. LOL Sounds dangerous, and like you would have feed problems. It is amazing what BS is out there. I myself try to get them as flush as possible.

10-20-2008, 07:45 AM	#3
Terry_P Advanced Senior Member Join Date: Mar 2008 Location: NH Posts: 2,513	Re: High Primers Seat them flush as high primers can be a real issue. I've seen double BBL's double up because of a high primer. In a semi auto I think they call it a slam fire?? __________________ NRA and NAHC Life "Both oligarch and tyrant mistrust the people, and therefore deprive them of their arms." -Aristotle

10-20-2008, 07:55 AM	#4
LDBennett Advanced Senior Member Join Date: Dec 2003 Location: Hesperia, CA Posts: 5,718	Re: High Primers NO reloading manual EVER suggests anything for primer height other than below flush. Flush is not even good enough. The primer has a small anvil inside it with legs that are designed to sit against the bottom of the primer pocket. When the firing pin strikes the back of the primer, it hits the anvil through the backside of the primer. If the primer is high then it has to first seat the anvils feet against the back of the primer pocket before any energy can be given to the primer compound. If it takes too much energy to seat the primer then there is not enough left for the priming compound to get ignited. Then there is the safety aspect. If the primer is high it can rest on the bolt face which can act as a big firing pin as the bolt slams closed. This can result in what is called a "slam fire" and in semi-auto guns it is a NO-NO. Any reloading source of information will advise that all primers MUST be seated below the face of the back of the cartridges or slam fires MAY occur. The only good source of reloading information is reloading manuals by large powder and bullet and reloading equipment manufacturers. Anything they print makes them liable so you can bet they researched and tested every recommendation in their manuals. The guy at the club or range who gives you a recommendation has no liabiltiy and can tell you anything he wants. He can take his own advice and suffer the consequences too. Don't be his guinea pig and take his advice. Stick to proven advice from an actual manufacture's reolading manual. BE SAFE! LDBennett Last edited by LDBennett; 10-20-2008 at 07:57 AM..

10-20-2008, 05:01 PM	#5
Bindernut Advanced Senior Member Join Date: Oct 2007 Location: ND, USA Posts: 2,453	Re: High Primers Never heard of any cartridge using high primers as a "normal". Sounds dangerous and you're setting yourself up for slamfires...or even a discharge if you drop a round on the concrete beside you! I think the local know-it-all is full of wind on that one! With clean primer pockets and good brass the primer should be seated slightly below flush.

10-21-2008, 03:00 AM	#7
TranterUK Advanced Senior Member Join Date: May 2008 Location: Cambridge UK Posts: 5,103	Re: High Primers High primers would be very dangerous indeed, with the potential for detonation of the cartridge 'before' it chambered, sending bits of brass all over. And the unlikely but not unknown chain detonation of the rounds in the magazine! __________________ DVC - Diligentia, Vis, Celeritas - Accuracy, Power, Speed. The light at the end of the recession tunnel IS a train coming the other way! Last edited by TranterUK; 10-21-2008 at 03:40 AM..

10-21-2008, 01:34 PM	#9
Dirtypacman Senior Member Join Date: Mar 2008 Location: Merrimac Valley, MA Posts: 908	Re: High Primers I have never heard of anyone reloading that looks to get anything but a flush primer. I have never read or heard anything positive about a High Primer. __________________ Member HHRG and HSC, NRA Life Member, GOAL Member LTC-A

10-21-2008, 03:25 PM	#10
LDBennett Advanced Senior Member Join Date: Dec 2003 Location: Hesperia, CA Posts: 5,718	Re: High Primers Dirtypacman: Not flush but below flush, but by only a thousandth or two.... you can just feel that it is below flush with your finger. My Dillon is designed so it only installs them one way: correctly and below flush. LDBennett

10-21-2008, 03:51 PM	#11
mrkirker Advanced Senior Member Join Date: Jul 2007 Posts: 3,067	Re: High Primers Loading a tube-type mag with 'high primer' ammo is a Recipe for Disaster! Don't even THINK of it!

10-21-2008, 10:22 PM	#12
312shooter Advanced Senior Member Join Date: Mar 2008 Location: Las Vegas NV Posts: 1,148	Re: High Primers Thank guys, I didn't have any intentions in doing so as I have never seen data that suggested this was a good move. I was interested to know if there was such a theory in our universe of reloading.

10-26-2008, 05:53 PM	#14
bobkk V.I.P. Member Join Date: Oct 2006 Location: E Tn. Posts: 59	Re: High Primers Bought a Ruger 44 carbine years ago. Well known manual said to use rifle primers if you were going to shoot them in a rifle. That didn't work they wouldn't seat flush. Glad I caught that on the first case. Primer pocket"s on pistol cases aren't as deep as rifle pockets.