large rifle primers or pistol primers

[Marlin Junky]

Bruce,

I did some fiddling with primer pocket depth tonight and discovered that when reaming Starline .44M cases to accommodate a Fed 210 one needs to remove about .005" to .007" before the primer seats flush or slightly countersunk. When removing this amount of brass, the web on a .44M Starline case is still .010" thicker than the web on a .45C Starline case. So there ya go... if you've got an action that'll handle 50K CUP, load the .44 Magnum up (gradually) and use rifle primers... or just be satisfied with the mundane.

MJ

[BluesBear]

44man, Good post and wonderful example of been there done that.
Some folks is slow learners though.


So this is my final contribution to this bruhaha.

Considering that a standard Large Rifle primer is of slightly greater brisance than a Magnum Large Pistol primer the following becomes very relevant;

Several years ago I was on the Buena Vista, Colorado, shooting range with my friend Allan Jones, editor of Speer Reloading Manual Number 12. I noticed that in this particular manual one of my favorite magnum revolver powders, Hercules (now Alliant) 2400, was giving rather low velocities in .357 and .44 Magnum cartridges, especially when compared with Hodgdon H-110 and Winchester 296 powders. I had also noticed the data had been obtained using CCI Magnum Pistol primers. I mentioned to Allan that in my experience with 2400, it had always given better accuracy, lower pressures and extreme spreads when ignited by a standard primer. And Hercules had always recommended using standard primers and never Magnums. Allan seemed genuinely interested, stating he would take a closer look at it upon returning to the Speer lab.

I thought little about our conversation until the Speer Reloading Manual Number 13 was published a couple of years later. In referencing it I noticed 2400 data for both the .357 and .44 Magnums had been "re-shot" using CCI 500 and 300 standard primers, respectively. This time, however, 2400 gave substantially higher velocities, while staying within SAAMI pressure limits. Allan even commented in the .357 and .44 Magnum chapters that when they changed from Magnum to standard primers, performance was "significantly improved."

In discussing this matter with Allan (as well as other labs), this change in components alone can affect pressures by as much as 20 to 25 percent. For example, one lab reported more than a 10,000 psi increase in pressure when changing from a CCI 300 to a 350 primer in .44 Magnum loads that were running 35,000 psi with 2400. (This illustrates the importance of using loads exactly as shown from a manual or reputable source.)

Now I'm all for experimentation. I've certainly done more than my share.
Years ago™, I wasted a lot of time and money experimenting with small rifle primers in Super .38 ACP. All I really did was blow out some case heads, crack a set of grips and ruin a couple of magazines.
So y'all go ahead and do it your way.
After all, who cares about better accuracy, lower pressures and smaller standard deviation?

[Whitespider]

There’s more to primer brisance than how “hot” it is. To say that primer X is hotter than primer Y doesn’t explain much. “Brisance” is used as a descriptive for the aggregation of things that happen when a primer ignites.

1) Energy
2) Pressure increase
3) Heat
4) Flame
5) Burning sparks/embers
6) Burn time

If primer X has more heat and sparks, but less flame and burn time than primer Y, which primer is “hotter” (has more brisance)?

A few years ago I was out of work for nine months. I spent that whole summer experimenting with primers in revolvers and rifles. I fired thousands of rounds over the chronograph. The more I experimented, the more confused I became. I did learn one very important lesson, primer choice is very important to load consistency.

I could come up with no “rule of thumb” when it comes to primers. Two different guns shooting the same loads may like different primers igniting the load. Increase the powder charge from a mid-range load to a high-end load in the same gun and a primer change may be required for load consistency. The same powder in two similar cartridges like different primers. Some magnum primers appear to have less brisance than some standard primers. It’s simply not true that slow burning ball powders always need a magnum primer. Etc., etc., etc.

But, one thing was quite obvious across the board. A primer that was “too hot” for the load was much more detrimental to consistency than a primer “too cold” for the load. A load with a “too cold” primer would show high ES/SD, but a load with a “too hot” primer would have wild velocity/pressure swings (as much as 400 fps in some loads).

All that said, I did find one revolver load that liked a small rifle primer. My Blackhawk .32-20 liked a 120gr. GC boolit, IMR 4227 and an old Herter’s Small Rifle primer I had in the cabinet. One rifle, a .22 Hornet did best with most loads using standard small pistol primers.

Just my TWO CENTS worth, if it’s worth anything.

[felix]

That is a great post for beginners, BB. None of the posts in this thread has talked about the pressure curve itself, and the problem associated in measuring the incremental values. All of the devices used are extremely slow in reaction. We are interested in how the container of the absolute pressure at any one location reacts to the pressure curve itself. If any one point is considered, that point of measurement should be at the weakest part of the container whatever that might be for the gun in question. Keep in mind the pressure curve is extremely dynamic because there are two ignitions, one for the primer, one for the powder. They overlap considerably and how that looks in detail is significant. ... felix

Addendum..........what whitespider said in his post is right on!!!!!!!!!!!

[9.3X62AL]

I'm certainly glad that a few posters in this thread are boolit casters and reloaders--and not physicians. Your bedside manner would kill patients.

NOTHING discourages learning like an arrogant, holier-than-thou, overbearing. didactic response to someone's question concerning an element of this hobby. NOTHING! I don't care how many years you or I have been shooting or handloading--AT SOME POINT IN THAT PROCESS WE WERE ALL NEW TO THE GAME. With that in mind, I respectfully request........no, I INSIST AND DEMAND that you treat others with tact and respect when responding to their posts. If that is a problem for you--THEN LEAVE, AND DON'T RETURN.

This is NOT intended to discourage disagreement, far from it. I made a living in an adversarial court system that has its flaws, but remains perhaps the best system for sorting questions of fact from fiction devised by man. I fully accept--no, I welcome debate and discussion. BUT DO SO WITH A LITTLE CLASS, FOR CRYING OUT LOUD. To demean someone, to strip them of dignity--is to invite a fight. If those are the invitations you want to send out, lose this mailing address.

In closing, I make no pretense of being an especially gifted firearms hobbyist. I do have some insight into the future, however.....and I predict we will be short a few members before the weekend is out.

[9.3X62AL]

BruceB, Whitespider, and Felix--

THANK YOU for your measured, informative responses to the original poster's questions. As always.

Silvyus--

You didn't start the heated part of the debate. No sweat.

[steveb]

Now I'm all for experimentation. I've certainly done more than my share.
Years ago™, I wasted a lot of time and money experimenting with small rifle primers in Super .38 ACP. All I really did was blow out some case heads, crack a set of grips and ruin a couple of magazines.
So y'all go ahead and do it your way.
After all, who cares about better accuracy, lower pressures and smaller standard deviation?

Gentleman, I have been handloading for around three years and I should have known better. Last week I ran out of WLP primers and decided to use LR primers I had laying around while loading for the 45ACP. I did not think (DUH! ) of possible higher pressures with the charge of Titegroup I was using, as I was to worried about the height of the primer. The primers height was just fine but something raised the pressure to the point of failure. I dont know if I accidentaly overcharged the case, but know for a fact I was using large rifle primers...NOT GOOD!!!.







I loaded up five rounds in the magazine for my Para-Ordnance and on the fourth shot it let go and blew the 5th cartridge out of the bottom of the mag through the floor plate. The magazine was blown out as well. The only thing this mistake done was stretch the magazine out a thousanth and I need a new floor plate. The rest of this Para-Ordnance is just fine and not hurt a bit. Thank goodness it has a ramped barrel or it could have turned out worse IMO.




I am lucky I wasnt hurt and WILL be using the intended primers from here on out....Steve.

P.S...Thanks again for checking out my Para Jim!

[9.3X62AL]

WOW--whatever happened, it ain't good! Glad to hear that you are safe and well. Did you look at the other fired cases to see what (if any) abnormalities were apparent?

SOBERING pic. Thanks for posting that.

[Marlin Junky]

Gentleman, I have been handloading for around three years and I should have known better. Last week I ran out of WLP primers and decided to use LR primers I had laying around while loading for the 45ACP. I did not think (DUH! ) of possible higher pressures with the charge of Titegroup I was using, as I was to worried about the height of the primer. The primers height was just fine but something raised the pressure to the point of failure. I dont know if I accidentaly overcharged the case, but know for a fact I was using large rifle primers...NOT GOOD!!!.

I can only speak for myself, but I don't think anyone ever suggested that a direct substitution of rifle primers for pistol primers in the .44 Magnum without first reducing the powder charge was condoned and I would only do so when handloading for a rifle such as the Marlin 1894, an original M92 in good condition or M92 Reproduction (I guess the Ruger M96 would be OK too). After reaming out the required metal in a .44M primer pocket to enable a couple thou. below flush seating of a Fed 210 primer in a .44M Starline case, (as above) I decided it's too much effort to convert a large batch of cases from LP pockets to LR pockets but that doesn't say I wouldn't do so if I could mechanize the process. Why would I bother? I probably wouldn't unless I purchased a M92 Repro in .44 Magnum... after all, the Marlin is not a 50K psi gun.

MJ

[44man]

I hope it wasn't me that started a debate! I only relate my experiences.
Steve's experience is what I am afraid of with the wrong primer. And I do blame the primer!
Could this be classified as an SEE event where the bullet is moved into the rifling by primer pressure, stops and then the powder burn pressure hits it?
Scary to say the least.

[Marlin Junky]

I hope it wasn't me that started a debate!

I don't think 9.3x62AL is discouraging debate. I personally would appreciate a more mature decorum though. Basically when I start reading a post and I don't like it's tone I just quit reading it at that point and don't really care if it contains useful information or not.

MJ

[MT Gianni]

I have some 357 loads that use a rifle primer. They are for Blackhawk only and were recommended and worked up to using that primer. More importantly is the basic handloaders advice that when you have a maximum load and change any component to drop back powder volumn and start over. Most of our cast loads are not warm so we tend to substitute with out reworking but should not forget this principle. Gianni

[felix]

Never out of the question, 44Man, but not probable in this PARTICULAR situation because of the choice of powder, which is known for easier ignition. Also, you can visualize the lack of chamber support (for a loaded round) which is inherent in guns having a large "loading" angle to allow various ammo specs to chamber. Typical for guns having short slides, such as auto pistols and pistol lever guns specifically. ... felix

[alamogunr]

I have nothing to add to this discussion except to say that I appreciate very much the educational aspects of this thread. I've never had any reason to try such a substitution, but without this information from those with more knowledge and first hand experience I might have been tempted somewhere down the road.

John

[Marlin Junky]

I have some 357 loads that use a rifle primer. They are for Blackhawk only and were recommended and worked up to using that primer. More importantly is the basic handloaders advice that when you have a maximum load and change any component to drop back powder volumn and start over. Most of our cast loads are not warm so we tend to substitute with out reworking but should not forget this principle. Gianni

Small primers all have the same cup height (unless something has changed in the last 5-10 years) and I've found with compressed charges of 296, a small rifle magnum primer in a strong .357 handgun (such as the Blackhawk) does a very good job of extracting the last bit of umph out of the lil' cartridge and certainly doesn't hurt in the accuracy department.

MJ

[buck1]

Silvyus ,
I think your question is fine ! You didnt ask about something not related.
As a rule, no dont use rifle primers in pistol cases unless called for, as in a .454 . But most of us here know that a caster is by nature a experimenter.
So often the so called facts are just wrong or at least open for discussion. And a little more input is a very helpfull thing. Most of us Know not everything you need is in a book somewhere. Sure LOTS of it is, but by no means all of it.
MOST here will be happy to help anyway we can with any reloading question you may have. So dont be discouraged by a ,what I belive to be a" more then a little rude" post.....Buck

[steveb]

I very well may have double charged this case to cause this. I also could have let one slip by with a high primer as well? I have tried to nail down THE reason for this but it could have been a couple different things. Here is a closer pic of the case head. Where the firing pin hit the primer is flat. It is hard to tell from the pic but the crater is flatter than a pancake.

[Fireball 57]

Thanks, ALL, for this informative and enlightening discussion! Substitution of components has varied results. Truly, "...We are all new to this game...!" SteveB: Glad to know you are okay!

Fireball

[Dragoon]

I very well may have double charged this case to cause this. I also could have let one slip by with a high primer as well? I have tried to nail down THE reason for this but it could have been a couple different things. Here is a closer pic of the case head. Where the firing pin hit the primer is flat. It is hard to tell from the pic but the crater is flatter than a pancake.

I guess you were too busy cleaning out your under pants to pick up the first three empties?

[kenjuudo]

I guess you were too busy cleaning out your under pants to pick up the first three empties?

Dragoon, He wasn't so rattled as to not pick the other cases up, they appear normal but do smell faintly like a used diaper. Looked like a double charge to me, although I'm sure the choice of primmer didn't help matters.

jim