Are Small Pistol Magnum & Small Rifle Primers Safe in 9mm?

[El Greco]

This question has been asked numerous times.
The video below will answer many questions.

https://www.youtube.com/watch?v=NGVRGsoOr6k&t=324s

[Joel Chavez]

Good stuff!

[Conditor22]

A knowledgeable member on this forum who does a lot of testing told me there was/is a flaw in the testing process/test and the results. I tend to agree with him.

I've tried exchanging spm for some of my favorite sp loads and the results were nowhere near as good. I'm not saying you can't get good groups/loads with spm in 9mm, I did a lot of testing in 357 and came up with good spm loads.

IF substituting spm or sr for sp I would start at the beginning load and work your way up watching pressure signs.

[Larry Gibson]

http://castboolits.gunloads.com/show...the-357-Magnum

Based on the test in that thread I would say it is not "safe' to substitute or use SP magnum or SR primers in the 9mm P cartridge.

But to each his own.

[Flailguy]

I've been using small rifle primers in 9mm for an ar using "start" load data. I hope this is safe...

[Sailormilan2]

9x23 Win cases, and ammo, come from the Winchester factory with small rifle primers. I often use small rifle primers in my hot 38 Super loads.

[Larry Gibson]

If the load was worked up, as it should have been, and the velocity does not exceed that of the same load with standard SP primers it might be "safe" and not exceeding at least the SAAMI MPSM. Yes, some do use SP magnum primers and SR primers w/o apparent pressure problems. But how do they know? Also some handgun cartridges are designed and made to use SR or LR primers but then those are used in cases and firearms designed for the psi they generate.

The problem is one of just substituting a SP magnum or SR primer in a "load" as was done in the video and implied to be safe. The video does not tell us what the load was. If one is using a maximum load developed with a standard SP primer and substitute a SP magnum or SR primer that is shown to increase psi then user beware is all I can say. We are all free to make our own choices (at least so far for the most part) and all I can say is substituting a SP magnum or SR primer in any of the 3 different 9mm P loads I use is not something I would do.

[Larry Gibson]

9x23 Win cases, and ammo, come from the Winchester factory with small rifle primers. I often use small rifle primers in my hot 38 Super loads.

You can bet your buppy Winchester didn't just substitute a WSR for a WSP in a given load w/o thorough testing.

I can pressure test those "hot 38 Super loads"?

[rancher1913]

keep in mind some powders are not substitution friendly while others tolerate it, does he say what powder was used.

[dtknowles]

From what I have gathered, the test in the video only proves that maybe you could get away with it in some cases. What Larry's test indicates is that there are probably cases where it would be a bad idea.

Anyone reloading who is not following closely loads listed in a manual is taking some risk. Even some manuals can't always be trusted, especially older ones as sometimes components change but keep the same names.

Tim

[Lloyd Smale]

for the most part load data in loading manuals these day are dummied down for liability reasons. If you doubt it look at a loading manual from 40 years ago. Ive shot mag pistol and small rifle in 9s and 40s. Never even saw a flattened primer using book loads. Only down side to it is i wish i had some of those small rifle primers back today. Now that said when i do it i start with the middle of the road load. Not the starting load and not the max. If i dont get pressure signs i slowly work up but usually stay right there because in all reality 50-100 fps isnt buying you much anyway. Most of my 9 shooting is cast bullet plinking. Its has kind of replaced 22lr in my house. Not going to war or self defense. for that i buy a box of factory (or did 20 years ago) and have a loaded mag in a defense gun. bottom line is if a mag primer makes your load so hot it blows a primer or ruptures a case or anything else unsafe your allready loading way above safe limits.

[JoeJames]

I am not hurting yet, for spp's, but I may load a few 38 Special standard loads - 3.8 grains Bullseye - 158 gr. Speer swaged swc, and in my S&W Model 67 they average 773 fps. That is of course with standard small pistol primers. And substitute CCI small rifle primers, and see how they run. I'd rather know now than later on and way on down the road.

[44MAG#1]

What Mr Smale said. If one drops back sufficiently from near max, watches pressure signs on the cases and works up like one should there should be no safety problem. Now if one is like a bull on a rampage and slaps a Mag or SR primer in just any load, I would say that person is, well, I will say it like this, something is wrong with their judgment.

[charlie b]

If you work back up how do you know you are not exceeding the pressure limits?

Remember that the primer cups for rifle and sometimes for magnum pistol are harder/thicker than standard pistol. Making a rifle primer flat means you are at rifle pressures, not something I would want in my pistol. I know I have not had a Rem 7 1/2 primer flatten in my .223. I'd hate to think of that much pressure in my 9mm.

Yes, I know I can get away with it sometimes. Modern pistols are made with better metals and can withstand a lot higher pressures, but.....

[Lloyd Smale]

If you work back up how do you know you are not exceeding the pressure limits?

Remember that the primer cups for rifle and sometimes for magnum pistol are harder/thicker than standard pistol. Making a rifle primer flat means you are at rifle pressures, not something I would want in my pistol. I know I have not had a Rem 7 1/2 primer flatten in my .223. I'd hate to think of that much pressure in my 9mm.

Yes, I know I can get away with it sometimes. Modern pistols are made with better metals and can withstand a lot higher pressures, but.....

like was said if your one that already pushes the limit on plus p handloads then its not for you. Most of us shoot cast and dont push to max levels anyway and like i said even if you do the books are giving you lawyer level loads anyway. All i can say is ive loaded THOUSANDS of 9s with small rifle and sm pistol mag primers and have yet to have even a flattened primer. Best get used to doing things like this because if you dont you might as well put your guns in the safe and lock it for the next 4 years at least. Bottom line is if you hurt a gun doing this then either your gun is a piece of crap or your not using a newer loading manual to find your loads. Id bet theres not a handloader here thats been doing it for more then 20 years that hasnt snuck past max loads listed in a manual at one time or another. Guns are usually proofed at 50 to a 100 percent above max listed pressures. So to blow one up you have to do something pretty stupid and theres no cure for stupid.

[44MAG#1]

If you work back up how do you know you are not exceeding the pressure limits?

Remember that the primer cups for rifle and sometimes for magnum pistol are harder/thicker than standard pistol. Making a rifle primer flat means you are at rifle pressures, not something I would want in my pistol. I know I have not had a Rem 7 1/2 primer flatten in my .223. I'd hate to think of that much pressure in my 9mm.

Yes, I know I can get away with it sometimes. Modern pistols are made with better metals and can withstand a lot higher pressures, but.....

If you look at the CASE as a pressure sign, how they resize compared to a "normal load" whatever that is and chrono the loads as you go up you can tell a safe load. The KEY is to work up and WATCH. If you work up 3 different lots of the same powder with everything else being the same the pressure won't be the same even with the same charge weights. Throw in the difference in different lots of the same primer too, plus some using range pick up brass and what could you have. It is the "Swallowing a Camel and gagging at a Gnat " complex as it were.
I do the same thing at times. After all we are just human.

[Larry Gibson]

for the most part load data in loading manuals these day are dummied down for liability reasons.

An erroneous assumption and a myth.

Many loads in manuals have lowered the loads in some cartridges simply because we have much better and more accurate methods of measuring not only peak pressure [that's all C.U.P. method measures] but the entire internal ballistics when the cartridge is fired. The additional older methods used such as case head expansion, flatness of primers, sticky extraction, etc. proved not to be really good indicators of the actual pressure. Additionally many "blow ups" of firearms are not caused by excessive pressure the firearm itself could not handle. Many were caused by the cartridge case rupturing from pressures it could not handle. In the case of the 9mm P in semi-auto handguns the case is definitely the weak link. Interestingly to note also that, because of the better pressure testing methods some cartridges actually have improved/increased increased loads. Because of the much better pressure testing equipment we also have several new cartridges, both handgun and rifle, that give much higher performance at higher pressure than before. The better methods of pressure measurement have led to better designs, stronger firearms and better powders to contain the higher pressures. But let us understand; the 9mm P is a 100+ year old design with many cartridge cases, handguns of design and steel not designed nor intended to take excessive pressures. We should remain aware of that fact.

Many semi autos leave a portion of the case unsupported [surrounded by steel if you will] in the area of the case head/web not supported by the feed ramp area. It is there that excessive high pressure most often causes the unsupported area of the cartridge case to rupture. Many times the frame, grips and magazines are damaged/destroyed along with injury to the shooters hand. That is the probable and potential problem with using SR primers in loads that develop higher excessive pressures in the 9mm P used in those handguns. If your loads using SR primers do not develop excessive pressure then there should be no problem in their use. However, unless you can actually measure the pressure of such loads how do you know?

[jsizemore]

for the most part load data in loading manuals these day are dummied down for liability reasons. If you doubt it look at a loading manual from 40 years ago. Ive shot mag pistol and small rifle in 9s and 40s. Never even saw a flattened primer using book loads. Only down side to it is i wish i had some of those small rifle primers back today. Now that said when i do it i start with the middle of the road load. Not the starting load and not the max. If i dont get pressure signs i slowly work up but usually stay right there because in all reality 50-100 fps isnt buying you much anyway. Most of my 9 shooting is cast bullet plinking. Its has kind of replaced 22lr in my house. Not going to war or self defense. for that i buy a box of factory (or did 20 years ago) and have a loaded mag in a defense gun. bottom line is if a mag primer makes your load so hot it blows a primer or ruptures a case or anything else unsafe your allready loading way above safe limits.

Please go to this site and discover the manufacturing changes that have happened over time.

http://www.ilrc.ucf.edu/powders/search.php

Alliant Bullseye for instance has 7 different samples. Test data shows their difference. I didn't even count the "Bullseye" produced by Hercules. Things change and the market demands product. You or I don't have the lab to test exactly the differences between old and new components. I'm sure legalities come into play in any decision. We do live in the USA. Doing the right thing and keeping the wolf at bay can go hand in hand. I appreciate keeping my parts and pieces.

[44MAG#1]

One can tell if the load is safe (relative term) even if one doesn't know the EXACT pressure which is sure to change with a different lot of powder and different lots of primers. Not to mention different brands of primers. So pressure are not EXACT but still an ever changing thing . Period. Most don't have pressure measuring equipment. So the old Gray Matter must kick in combined with a chrono. Pressures of loads changes. No loads stay the same.

[kevin c]

Small rifle primers are used in the major power factor loads of some USPSA competitors, which often are high pressure. Here, though, it's not the primer making the load hot, but the powder charge.

Not saying it's a good idea, just that it's done.