Non-magnum primers in .357 cases - OK to use?

mjrodney · August 16, 2006, 08:42 AM

I managed to reload some .357 cartridges with standard small pistol primers, rather than magnum primers.

Bullseye powder, nothing heavy.

Should I expect any difficulty firing these reloads?

gb_in_ga · August 16, 2006, 08:46 AM

Nope. You usually only have to use magnum primers when loading heavy loads of slow burning powder. Fast burning powders like Bullseye should work just fine with standard small pistol primers.

**Mike Irwin** · August 16, 2006, 09:18 AM

I use standard small pistol primers in all of my .357 loads, including heavy charges of 296.

Never noticed any problems at all. Unless exceptional accuracy is a problem...

Smokey Joe · August 16, 2006, 10:27 AM

Mrjrodney--I think the issue here that you are asking about is the SIZE of the small pistol "regular" primer vs. the size of the small pistol magnum primer. They are the same size.

The "magnum" in .357 Magnum does not refer to the size of the primer pocket, rather to the length of the case. It is a lengthened .38 Special case, to hold a larger powder charge in a heavier-frame revolver.

I use my .357 Magnum for target shooting (it's a S&W 586) with small charges of Win 231 powder, 148 grain wadcutter bullets, and small pistol primers.

I use the same gun for hunting with a large charge of 2400, 180 grain hardcast flatnose gas-checked bullets, and magnum small pistol primers.

No problems either way. I expect you will find the same.

mjrodney · August 16, 2006, 11:08 AM

Thanks for the info.

Another wee nugget of reloading data to add to my collection.

Ben Shepherd · August 16, 2006, 04:33 PM

Look in you manuals carefully. When you are talking about primers, magnum refers to the relative ingnition charge in the primer, not the caliber.

Easy to ignite powders, like the bullseye you are using use standard primers. The harder to ignite powders like 296/H110, use the magnum version.

For instance, speers current manual has asterisks next to certain powders, when you find the asterisk at the bottom of the page it says "magnum primer used with this powder."

You SHOULD be using standard primers with bullseye.

stinger · August 16, 2006, 07:49 PM

I have never used a magnum primer. I wouldn't use a magnum primer unless I was having a problem with powder being left behind, and then only after starting over and redeveloping the load from scratch.

roger1shot · August 19, 2006, 06:28 AM

Hey
Called Sierra,bullet Tec yesterday.
I was calling about a load for my 38 spl.
I had two different powders.
One was Blue Dot,and the other Herco powder.
Asked about the use of primers.
The Tec said:Not to use the Mag. primer with the Blue Dot .38spl load.
But use the Mag. Primer with the Herco .38spl load.
Tec said not to inter change the Primers with the different powders.
Hope this helps.
Call Sierra Tec's,they are very helpful I talked to Robert.

roger1shot · August 19, 2006, 06:36 AM

Note:
On my last post I'm SORRY.
I should have looked at what I was sending better.
I got the two Powers, Blue Dot And Herco mixed UP on my last post.
Blue Dot gets the Mag.PRIMERS
I've been up toooo long.
But call a bullet Tec,for help that's the best way.
Someone may get things mix up.
And as we all know,reloading has to be done right the first time
everytime.

revolverman357 · August 19, 2006, 10:15 AM

For the .357 magnum I use 14gr 2400 powder with Federal 100 small pistol primers (not magnum), with a 158gr SWC hard cast bullet. This is the load my papa passed down to me. To some it is "old school", but It shoots great and no unburned powder left behind.

Peter M. Eick · August 19, 2006, 04:53 PM

If you go look at the load books or some of the online posts, the mag vs. no mag primer question for the 357 seems to be an on again off again thing. I don't think there is a consistent answer for it so far.

I tend to follow the load books and use what they call for. Interesting though with 2400 and 158 grn lead loads, about 1/2 the books call for a mag primer and about 1/2 don't.

Ben Shepherd · August 19, 2006, 05:10 PM

GENERAL(not absolute) rule:

If it's a ball or short stick type powder, magnum primers.

If it's a flake powder then standard primers.

Again this is a GENERAL rule, not an indisputible, or correct in all cases fact.

MADISON · August 20, 2006, 09:47 AM

I have used standard Winchester priimers to load my .357 Magnum [2400] for 30 years.

JJB2 · August 20, 2006, 04:24 PM

i use winchester standard primers for .38 spl and .357 mag loads too... have for years..... i do use bullseye exclusively though for moderate too fairly heavy loads in my .357 mag loads.... FWIW...........

LIFE IS SHORT...................................

August 16, 2006, 08:42 AM	#1
mjrodney Senior Member Join Date: March 5, 2006 Location: SW Florida Posts: 435	Non-magnum primers in .357 cases - OK to use? I managed to reload some .357 cartridges with standard small pistol primers, rather than magnum primers. Bullseye powder, nothing heavy. Should I expect any difficulty firing these reloads? __________________ Proud supporter of the NRA

August 16, 2006, 08:46 AM	#2
gb_in_ga Senior Member Join Date: February 15, 2005 Location: Pensacola, Fl Posts: 3,092	Nope. You usually only have to use magnum primers when loading heavy loads of slow burning powder. Fast burning powders like Bullseye should work just fine with standard small pistol primers. __________________ COME AND TAKE IT http://www.tamu.edu/ccbn/dewitt/batgon.htm Formerly lived in Ga, but now I'm back in Tx! Aaaand, now I'm off to Fla...

August 16, 2006, 09:18 AM	#3
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,388	I use standard small pistol primers in all of my .357 loads, including heavy charges of 296. Never noticed any problems at all. Unless exceptional accuracy is a problem... __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

August 16, 2006, 10:27 AM	#4
Smokey Joe Senior Member Join Date: July 14, 2001 Location: State of Confusion Posts: 2,106	Primer sizes Mrjrodney--I think the issue here that you are asking about is the SIZE of the small pistol "regular" primer vs. the size of the small pistol magnum primer. They are the same size. The "magnum" in .357 Magnum does not refer to the size of the primer pocket, rather to the length of the case. It is a lengthened .38 Special case, to hold a larger powder charge in a heavier-frame revolver. I use my .357 Magnum for target shooting (it's a S&W 586) with small charges of Win 231 powder, 148 grain wadcutter bullets, and small pistol primers. I use the same gun for hunting with a large charge of 2400, 180 grain hardcast flatnose gas-checked bullets, and magnum small pistol primers. No problems either way. I expect you will find the same. __________________ God Bless America --Smokey Joe

August 16, 2006, 11:08 AM	#5
mjrodney Senior Member Join Date: March 5, 2006 Location: SW Florida Posts: 435	Thanks for the info. Another wee nugget of reloading data to add to my collection. __________________ Proud supporter of the NRA

August 16, 2006, 04:33 PM	#6
Ben Shepherd Senior Member Join Date: August 11, 2001 Location: Utah Posts: 1,462	Look in you manuals carefully. When you are talking about primers, magnum refers to the relative ingnition charge in the primer, not the caliber. Easy to ignite powders, like the bullseye you are using use standard primers. The harder to ignite powders like 296/H110, use the magnum version. For instance, speers current manual has asterisks next to certain powders, when you find the asterisk at the bottom of the page it says "magnum primer used with this powder." You SHOULD be using standard primers with bullseye. __________________ From my cold dead hands......... NRA certified rifle, pistol and shotgun instructor. Hunter education instructor

August 16, 2006, 07:49 PM	#7
stinger Senior Member Join Date: November 6, 2001 Location: west texas Posts: 772	I have never used a magnum primer. I wouldn't use a magnum primer unless I was having a problem with powder being left behind, and then only after starting over and redeveloping the load from scratch.

August 19, 2006, 06:28 AM	#8
roger1shot Senior Member Join Date: July 20, 2005 Location: TEXAS Posts: 102	Primers Hey Called Sierra,bullet Tec yesterday. I was calling about a load for my 38 spl. I had two different powders. One was Blue Dot,and the other Herco powder. Asked about the use of primers. The Tec said:Not to use the Mag. primer with the Blue Dot .38spl load. But use the Mag. Primer with the Herco .38spl load. Tec said not to inter change the Primers with the different powders. Hope this helps. Call Sierra Tec's,they are very helpful I talked to Robert.

August 19, 2006, 06:36 AM	#9
roger1shot Senior Member Join Date: July 20, 2005 Location: TEXAS Posts: 102	NOTE: Last Post Was Wrong''' Note: On my last post I'm SORRY. I should have looked at what I was sending better. I got the two Powers, Blue Dot And Herco mixed UP on my last post. Blue Dot gets the Mag.PRIMERS I've been up toooo long. But call a bullet Tec,for help that's the best way. Someone may get things mix up. And as we all know,reloading has to be done right the first time everytime.

August 19, 2006, 10:15 AM	#10
revolverman357 Junior Member Join Date: July 30, 2006 Posts: 9	For the .357 magnum I use 14gr 2400 powder with Federal 100 small pistol primers (not magnum), with a 158gr SWC hard cast bullet. This is the load my papa passed down to me. To some it is "old school", but It shoots great and no unburned powder left behind.

August 19, 2006, 04:53 PM	#11
Peter M. Eick Senior Member Join Date: August 3, 1999 Location: Houston, Texas Posts: 2,991	If you go look at the load books or some of the online posts, the mag vs. no mag primer question for the 357 seems to be an on again off again thing. I don't think there is a consistent answer for it so far. I tend to follow the load books and use what they call for. Interesting though with 2400 and 158 grn lead loads, about 1/2 the books call for a mag primer and about 1/2 don't. __________________ 10mm and 357sig, the best things to come along since the 38 super!

August 19, 2006, 05:10 PM	#12
Ben Shepherd Senior Member Join Date: August 11, 2001 Location: Utah Posts: 1,462	GENERAL(not absolute) rule: If it's a ball or short stick type powder, magnum primers. If it's a flake powder then standard primers. Again this is a GENERAL rule, not an indisputible, or correct in all cases fact. __________________ From my cold dead hands......... NRA certified rifle, pistol and shotgun instructor. Hunter education instructor Last edited by Ben Shepherd; August 22, 2006 at 08:23 AM.

August 20, 2006, 09:47 AM	#13
MADISON Senior Member Join Date: January 1, 2000 Location: Roanoke, Virginia Posts: 2,678	Non magnum primers OK in .357? I have used standard Winchester priimers to load my .357 Magnum [2400] for 30 years.

August 20, 2006, 04:24 PM	#14
JJB2 Junior member Join Date: December 14, 2005 Posts: 558	i use winchester standard primers for .38 spl and .357 mag loads too... have for years..... i do use bullseye exclusively though for moderate too fairly heavy loads in my .357 mag loads.... FWIW........... LIFE IS SHORT...................................