magnum primers
- Thread starter jjcbuck
- Start date
It's my understanding that magnum primers are needed with powders that are inherently harder to ignite. Not all magnum chamberings need them. I've shot loaded .357 mag and .41 mag with powders that didn't need magnum primers.
I have read that magnum primers may themselves put off more energy than standard primers. That energy needs to be accounted for if you are loading max or near max rounds. That part is all academic to me as I don't have any powder that needs magnum primers.
I have read that magnum primers may themselves put off more energy than standard primers. That energy needs to be accounted for if you are loading max or near max rounds. That part is all academic to me as I don't have any powder that needs magnum primers.
My understanding has always been that of Ocraknife. Among the considerations in selecting the primer is the powder to be ignited, powder type, amount of powder and case volume. Powders like ball powders or spherical powders frequently call out a magnum primer. Anyway, I run with what the manual or load data calls for most of the time.
Ron
Ron
Ocraknife is correct.
Magnum primers are rarely (if ever?) needed for 9mm. The case is so small that a standard primer is going to inundate its entire internal volume immediately upon ignition.
That said, I have done lots of load work ups with 9mm using magnum primers. I did work ups for long-term ammo storage consideration. The theory being that the hotter primer will still deliver good ignition 10 - 20 - 30+ years down the road.
Magnum primers are rarely (if ever?) needed for 9mm. The case is so small that a standard primer is going to inundate its entire internal volume immediately upon ignition.
That said, I have done lots of load work ups with 9mm using magnum primers. I did work ups for long-term ammo storage consideration. The theory being that the hotter primer will still deliver good ignition 10 - 20 - 30+ years down the road.
Some claim that mag primers are an advantage when loading ball powders such as W748. I tested side by side in .223 using nosler 69 cc' s and even shot through a chrony and observed no measurable difference. Generally its suggested to use mag primers when you exceede 50 gr of powder. However im loading 460 S&W mag pistol with 50 gr of H110 (ball powder) using standard cci primers and getting excellent performance and a complete burn. (Strictly just my observences)
It's from another forum, but there is a lot of useful info on primers:
http://www.sksboards.com/smf/?topic=56422.0
http://www.sksboards.com/smf/?topic=56422.0
Small pistol magnum primers are never called for for normal 9mm loads. The powders normally used in the small capacity of the 9mm case do not require magnum priming. Handloaders loading for 9mm major frequently use small rifle primers because of their harder cups to contain the excessive pressure generated to attain major power factor out of the 9mm case. In this application the CCI550 small pistol magnum primer could be used. It is the same as the CCI400 small rifle primer.
mmb 713 writes in part:
My understanding is the CCI 550 small pistol magnum primer and the CCI 400 small rifle primer are not the same. Following several reads making the claim they were the same I contacted CCI.
The following is a portion of my correspondence to CCI:
The CCI Reply I received from CCI:
In addition to the email exchange I also did call CCI and was told the same thing over the phone. For anyone wishing to confirm this I suggest a phone call to the nice folks at CCI. Every time I have called them or emailed them with a question they have been happy to answer my questions and provide any requested data. Anyway, those curious may want to affirm what I have just stated in that the mentioned primers are not the same.
When loading certain handgun cases, the 454 Casull comes to mind, it is not unusual to see a Small Rifle primer called out such as the Federal 205. However, do not take the mentioned CCI primers to be one in the same as they are not.
Ron
My understanding is the CCI 550 small pistol magnum primer and the CCI 400 small rifle primer are not the same. Following several reads making the claim they were the same I contacted CCI.
The following is a portion of my correspondence to CCI:
The CCI Reply I received from CCI:
In addition to the email exchange I also did call CCI and was told the same thing over the phone. For anyone wishing to confirm this I suggest a phone call to the nice folks at CCI. Every time I have called them or emailed them with a question they have been happy to answer my questions and provide any requested data. Anyway, those curious may want to affirm what I have just stated in that the mentioned primers are not the same.
When loading certain handgun cases, the 454 Casull comes to mind, it is not unusual to see a Small Rifle primer called out such as the Federal 205. However, do not take the mentioned CCI primers to be one in the same as they are not.
Ron
NorthernBlue
New member
I recently started loading 9mm and chose to go with CCI 550s because the price difference is nil and I would assume they might help ignite the powder better in cold weather.
The reason for NOT using magnum primers in 9mm is that it is not called for in virtually any 9mm data. You can use magnum primers in a pinch, as I'm sure many here did in 2009 and 2012 because SP primers were scarce. I have a backup supply of SMP primers I purchased by mistake. I'll use them during another run.
In any event, work up your load if you ever have to switch to SMP primers as there can be a slight (probably not super significant) pressure difference.
Magnum primers are designed to make more gas than standard primers. This is because, for best burning, powders need a minimum starting pressure, and when a case gets larger than normal (magnum) it takes more gas to reach that pressure. Hence, magnum primers.
In addition to the pressure difference, in 1989 CCI changed the primer mix formulation to better ignite the 1960's era spherical powder formulations, whose heavy outside deterrent coatings can cause them to need not only higher start pressure to ignite consistently, but a hotter spark, so metal particles were added to make more thrown sparks. Alan Jones once worked for CCI and reported that in this article. So they may be used where their added start pressure is not required, but the sparks are.
Reloadron,
Call CCI back and ask if the amount and type of priming mix in the 550 and 400 are the same? One fellow reported talking to them and having them say that it was. That doesn't mean the primer cups are the same thickness, though. I would expect the rifle types to be thicker as rifle firing pins generally strike harder than a lot of revolvers do and typical pressures are higher. But if that reported information is correct, then a handgun that hit hard enough to produce reliable ignition with the 400's could use them in place of 550's. Assuming the cups are different, I would hesitate to try the reverse out of concern for getting a pierced primer.
One of the things Alan Jones reported was that primer design changes more frequent than people realize, so it is possible for something to be true at one time, then untrue a couple of years later. One has to keep updating one's information, alas.
In addition to the pressure difference, in 1989 CCI changed the primer mix formulation to better ignite the 1960's era spherical powder formulations, whose heavy outside deterrent coatings can cause them to need not only higher start pressure to ignite consistently, but a hotter spark, so metal particles were added to make more thrown sparks. Alan Jones once worked for CCI and reported that in this article. So they may be used where their added start pressure is not required, but the sparks are.
Reloadron,
Call CCI back and ask if the amount and type of priming mix in the 550 and 400 are the same? One fellow reported talking to them and having them say that it was. That doesn't mean the primer cups are the same thickness, though. I would expect the rifle types to be thicker as rifle firing pins generally strike harder than a lot of revolvers do and typical pressures are higher. But if that reported information is correct, then a handgun that hit hard enough to produce reliable ignition with the 400's could use them in place of 550's. Assuming the cups are different, I would hesitate to try the reverse out of concern for getting a pierced primer.
One of the things Alan Jones reported was that primer design changes more frequent than people realize, so it is possible for something to be true at one time, then untrue a couple of years later. One has to keep updating one's information, alas.