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Discussion Starter · #1 ·
A friend of mine recently passed away who had amassed a decent amount of reloading components. I was offered to buy some items from his hoard. Over the phone I agreed to purchase 7,000 small pistol primers (among other items) at a price I couldn't refuse.

Upon taking delivery I discovered I just purchased 7,000 Federal Small Pistol MAGNUM primers.

.... I've never used these as I've never seen a need for Magnum primers. My loads are seldom max loads and rarely with slow burning powders. I can see using these with my H110 .357 mag loading but at that rate I just bought a lifetime supply :D

My question, can I use these primers SAFELY in other loadings such as .357 loads with Unique or Accurate #7, .38 Special loads with fast burnings powders (TiteGroup, Bullseye, 700X), or .40 S&W loads with AutoComp, PowerPistol, or Accurate #7 ????
 

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I would not use them unless your load data calls for them.

Why not try to trade them for regular SP primers.
 

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sure
just back down the charge a bit if your gettin up there anyway

i just ran thru a bunch in .40
was a midrange load anyway so i didnt change a thing
never noticed a difference

the cups may be a bit harder on some brands
so if you have a light sprung gun you could have issues
but ill bet youll never notice the difference

we worry about things which is good!

but doesnt winchester sell one LP primer now?
does says right on the package for both magnum and standard loads
 

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Discussion Starter · #4 ·
I would not use them unless your load data calls for them.

Why not try to trade them for regular SP primers.
Hey moakes... wanna trade??? ;)
 

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You can use a magnum primer for any load. If you don't shoot near max loads, you likely won't have to change a thing, but it sure won't hurt anything to back the load off a few percentage points and work your way back up
 

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Owly, Here's a clip from an earlier post I made on a similar subject:
Just some FYI about magnum primers .... the very purpose of magnum primers is to get positive ignition with "hard to ignite" slow burning powders such as H-110 / W-296 when used in magnum cartridges such as a 357 Mag, 41 Mag, 44 Mag, etc. Indeed, loads with some slow burning powders (not all of them) require magnum primers or you risk squib loads. This is especially important in cold weather where these powders are even harder to ignite.

Magnum primers do two things .... the first being they develop more flash which is much like adding more powder to the charge. Second, they cause ALL powders to burn faster ... even if the powder charge is reduced. When powders burn faster, they create higher initial chamber pressure. Herein lies the problem if you use magnum primers in a cartridge designed for standard primers (ie 9mm). Pressure will indeed increase and if you don't have pressure measuring equipment, you may be well over the SAAMI rating, which could demo your gun and possibly injure the shooter. In other words, using magnum primers in anything but a magnum cartridge with certain slow burning powders is very risky and could end up in disaster.

Don't depend on a chronograph to "guess your pressure". Here's why: when powder burns faster, it creates very high initial chamber pressure and because higher chamber pressure makes the powder charge burn up in less bullet travel, the velocity of the exiting bullet may actually be slower than the same powder charge with a standard primer. In other words, using a magnum primer will elevate chamber pressure but may not increase velocity ... it could even clock a slower velocity.

My best advise is ... never use magnum pistol primers unless they are specified in your reloading manual. There's a lot more information about powders and primers in my article posted in the Forum Library titled "Mysteries of Smokeless Gunpowder". Here's a link: http://rugerforum.net/library/29181-...gunpowder.html
 

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I don't think I would use them with fast burning powder as stated above. Either save them for the H110/WW296 and have a lifetime supply or find a fellow reloader who wants to swap out.
 

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Discussion Starter · #8 ·
Thanks for the replys guys. Looks like I've got a lifetime supply indeed. Kind of what I assumed, but hoped otherwise.

Now to find a lifetimes worth of H110.....
 

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Many ball powders like Power Pistol perform better with magnum primers producing lower SD, higher velocities, and more complete ignition even in hot weather. Yes, you have to work up your loads when you try magnum primers but you should also do it when you switch brands of standard primers too.

Why? Because there are standard primers and then there are standard primers, BR and BR, etc. Fore example, Winchester doesn't produce a SRM primer at all claiming that their SR primer is powerful enough for both types while both CCI and Remington produce both types. Same with LP primers, Winchester and Remington don't produce LPM primers but Federal and CCI do.

Different manufacturers' primers produce different heat flashes so to say that a load only should use a standard primer is suspect at best, wrong at worst. Check out these pictures of different brands of primers igniting on 6MMBR.com for an idea of the differences between manufacturers BR primer performance.
 

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start with a charge from the bottom of your data and work up in small increments. when primers were impossible to find I used magnums primers with no sign of excess pressure. reduced charges to below mid range and found my happy spot. kept notes and saved them for any time this happens again. like if the hildabeast gets elected.
 

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COSteve, Interesting photos in your reference but they really don't tell you much about the ignition attributes. Who ever did the article should spend a little more time on research .... PMC primers are made in South Korea, not Russia .... not that it would change the photos.

Primer flash is measured by two distinct attributes .... time and temperature. These two attributes combine to form "power" .... no different than combining a gunpowder's attributes of burn rate with the charge weight. With Magnum primers, more "mix" is used to extend the time of the flash and the mix is formulated to produce a hotter flash. These two combine to make slow burning powders ignite better with a hotter and longer flash duration.

Standard primers have less "mix" and are formulated to produce a colder flash. Again, combining these two attributes will allow all fast and medium burn rate powders to ignite properly. The difference between brands of Standard primers is .... one brand may use a faster burning mix that burns hotter while another brand may use a slower burning mix that burns colder. All US made standard primers are interchangeable and will end up producing about the same flash power, however one may favor time, the other may favor temperature. This is why some powders prefer one brand of primer over another for optimum accuracy.

When you add the other main variable .... gun powder, the situation will change radically. ALL powders will burn faster when ignited by a magnum primer ... no exceptions. This means if you have a mid-burn rate powder and use magnum primers, in essence you now have fast burning powder that could very easily go over SAAMI established max pressure. The absolute worst case scenario is using a Mag primer with fast burning powder in a small capacity case (ie 9mm). This could cross the line between a propellant and an explosive, and believe me, you don't want to go there.

Going the other direction .... if you have a slow burning powder such as W-296/H-110 ignited by a standard primer, the already slow burning powder will burn even slower. It may burn so slow that the fire literally goes out and turns the load into a squib. In nearly all cases where a mag primer is specified and a standard primer is used, max velocity spreads will be much wilder, which in turn affects accuracy. This is especially true at colder temperatures where slow burners are much harder to ignite.

If you experiment by exchanging standard primers with magnum primers .... at best it is a guessing game. The only predictable results are .... chamber pressure will increase due to the powder burning faster. How much will it increase???? Only pressure testing equipment could say for sure. There is no direct correlation between chamber pressure and velocity so when powder burns faster, it doesn't necessarily mean velocity will be higher, in fact a mid-burn rate load may actually chronograph slower with a magnum primer, which if you didn't know better, would give the false impression of lower chamber pressure. Sometimes these counterintuitive results end up in blown up guns.

My suggestion .... let a SAAMI approved lab do the testing to determine chamber pressure .... not me trying to out-guess reality, and not in my guns.
 

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Bought three hundred by mistake one day, loaded them up for my P95 using 700 X powder at a reduced charge, ran fine for me.
 

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Discussion Starter · #16 ·
So, you're going to ship haz-mat? Are you a licensed haz-mat shipper?
Sorry RalphS, local pick up only. If you need a few thousand primers just let me know the next time you're coming through northern WI.
 

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I hear and understand what you're saying, I'm just not convinced that your basic assumptions are as absolute as you believe. I don't have any hard data to support or dispute them but I'm not prepared to take your correlations at face value. We're talking the physics of combustion here and one thing I know is that physics isn't easily understood by the likes of mere mortals.

How do I know? My son is a low temperature physicist working at NIST, a national lab in Boulder, CO and he reminds me how difficult the science is every time he tried to explain to me what he's working on. (Something about tunnel junctions, 100-300 milliKelvin cooling, and other stuff I don't have a clue about).

I agree, primers are more complex than 'smack it and stand back' but flame size and temperature are also only two of the components as burn time is also a factor (same as 'area under the curve' pressure plots). Further, as the 'average' time a round is actually in the barrel of a typical rifle is on the order of 1/4,000 of a second, this time and temp curve is happening really, really fast so slight variations have little time to act on the powders.

I was always taught that the burning powder was what accelerated the burn rate as its orders of magnitude larger than the burn from the primer. Maybe that's a wives tale and maybe that's based in fact. At this point this whole discussion is way over my knowledge base.

What I know from first person, personal test data is this. Magnum primers igniting ball powders in my handloads such as WC844, H335, TAC, BLC-(2), W748, W760, Power Pistol, H110, and WC297 all produce lower measured Standard Deviations (SD), lower Extreme Spreads (ES), and slightly higher velocities for a given powder load in my firearms (dozens of them) than the same loads with standard primers with the same loads, in the same firearms, fired at the same time, measured with the same chronograph.

These results are as tested by my chronograph on multiple occasions. Rifle or pistol, it doesn't matter, the results are always the same. Further, there has been no evidence of excessive pressure signs by observing the primers (a crude measure at best), nor any measurable differences in the case bases or primer pockets indicating excessive pressure. Whether I'm fooling myself or just using the proper ignition source for the application, I'm happy with my results, have 10s of thousands of rds down range with no apparent weakening of the brass or damage to the firearms.
 

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COSteve, I find most of your posts are contradicting established facts about primers, powders, and now even chamfering case mouths. Did you miss out on reloading 101 somewhere along the way???

A typical 223 Rem bullet spends about 1 millisecond in the bore ... 1/1000 of a second. In a typical handgun with a 6" barrel, the bullet will spend about .5 milliseconds in the bore or 1/2000 of a second. To achieve 1/4000 sec in a rifle, the velocity would have to be about 12,000 fps or 2000 fps in a 6" pistol. Considering smokeless powder gases expand at about 6000fps, it would be impossible to achieve 12,000 fps from any firearm. That said, even 1/1000 second is pretty quick so just a slight variation in primer flash duration or temperature can make a notable difference in powder ignition.

I was always taught that the burning powder was what accelerated the burn rate as its orders of magnitude larger than the burn from the primer
Huh? that doesn't even make sense. Just to clarify .... burn rate is a property of the specific powder and is influenced by bullet seating depth, diameter of the bullet, weight of the bullet, powder charge weight, and of course the primer. In other words, anything that changes chamber pressure, also has to change the powder burn rate in a similar manner. In the previous discussion, we were discussing primers so keeping with the same concept, a magnum primer will ALWAYS cause powder to burn faster, thus it will increase chamber pressure by a proportional amount. There aren't any powders in the world that deviates from this concept. Also as I mentioned before, just because chamber pressure increases, it doesn't mean velocity will increase, in fact sometimes velocity is lower with a mag primer.

Magnum primers were designed to ignite a large volume of slow burning powder ... commonly found in magnum rifle cartridges and a few magnum revolver cartridges. If you look at a powder burn rate chart, starting with the fastest burn rate, you will see ... as powders get progressively slower burning, there is a point where magnum handgun powders transition into fast burning rifle powders. W-296/H-110 is about the point of transition where it can be used in a magnum revolver cartridge or a small capacity rifle cartridge such as a 22 Hornet. As rifle cartridges increase in size and bullet diameter, the powder used will get slower and slower burning but will still use a standard rifle primer. When you reach magnum velocity rifle cartridges, powder burn rates are exceptionally slow and take a very strong primer flash to ignite the long column of powder. This is where a magnum rifle primer is used. People that aren't familiar with how powder burn rates work, often choose the wrong powder for a specific load then wonder why it didn't shoot well. Yes, reloading manuals are guilty of listing powders in the wrong burn rate ... but they will go bang and puke a bullet out the bore without blowing the gun up.

It's very interesting .... since piezo transducers started being used to plot actual pressure curves in gun barrels, the shooting industry has learned a lot about primers. Some of the things learned were very contradictive to previous theories ... some were amazingly accurate considering the crudeness of prior pressure testing equipment. With multiple transducers coupled into a computer, the pressure curve can be plotted in pounds per square inch from the time the primer flashes until the bullet leaves the muzzle. Based on the results of these tests, I will make a profound statement .... If you are loading a non-magnum rifle cartridge and you need a magnum primer for better max velocity spreads, you chose the WRONG POWDER! Likewise with handgun powders!
 

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After much experimentation, I have switched to nothing but CCI 550

Small Pistol Magnum primers for all small pistol loads.

Start at minimum charge level, you'll usually find you get same results but with less

powder. HS-6 in 9mm with 124gr projectiles is absolutely awesome with Magnum primers

and every 9mm pistol I've fired them through.

Just basic common sense, using magnum primers for all loads is perfectly

safe as long as standard practice of starting low and working up are followed.
 

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johndm1967,
Just basic common sense, using magnum primers for all loads is perfectly safe as long as standard practice of starting low and working up are followed.
Using magnum primers in 9mm cases is NOT basic common sense ... it is potentially very dangerous!!! Tell me why you NEVER see 9mm loads listed in any reputable reloading manual that utilize magnum primers???? In case you don't know ... I'll tell you why. Magnum primers force all types of powder to burn faster. This can easily elevate chamber pressures well over established SAAMI standards.
 
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