Magnum Primers...How Much Difference?

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snubbiefan

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I came across some 400 primed 38-special brass cases. I have no idea how they are primed. I loaded a few up with my normal light-load for the wife and there is a LARGE disparity in both report and recoil. I used the same amount of Bullseye (2.5 grains) in each and every case under a 105-grain cast LSWC and am sure I have not double-charged a single one. I do that by hand...one case at a time and out of the 25-or-so that I fired....most were hotter than I had expected and I could not have double charged that many by accident anyway.

My ?...will just the priming with magnum primers under the exact same charge and bullet weight/design make a noticeable difference in report, recoil and power? I'm not breaking any wrist here mind you....I just noticed a decided difference between these and the ones I prime with small pistol primers.

Obviously....I have never used magnum primers before.
 
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I've found less than 50 fps difference between the two in 38 super applications. I doubt it's perceptible.

I'll clarify I'm using Federal 100's & 200's
 
I've never noticed a difference in the sound or feel of a load using magnum primers vs standard.If you have any left you might take a few apart and check the powder charge.
 
I think I need to take all these recent re-loads and shoot them in my 686. I do not want to blow any of my J's apart. I know that none of us ever feel guilty and I cannot believe I would have screwed up the charge in that many rounds. I was using a calibrated dipper and building 5-or-10 at a time.

Think I'll go back to square one and recalibrate.....get my head out of my butt and try this all again.
 
Stuff happens.Been reloading for 30 years and not too long ago managed to make a pair of squibs on a single stage.Still don't know how I did that.
 
Snubbiefan,
Think of it this way - the primer is your spark plug with provides your mixture in the cylinders with the spark needed to "get the ball rolling" so to speak. Their are "hotter" plugs for longer trips for better gas milage and for extream weather conditions. Magnum primers are not much different in what they are used for. Magnum primers are most effected by the type of powder used and extreaming weather. An example is if you are using your rounds for hunting an expect temps to be 20 or below, a magnum primer will provide a better hotter spark than a standard primer.

Now the difference in your loads, my only thoughts are
1. carefully check each powder charge for correct weight.
2. make sure your OAL is consistant each time.
3. set your crimp for a lighter amount, the heaver the crimp the more you increase the pressure.
4. Don't leave your loads exposed to direct sun for long(er) pierods of time. We used to do that in pistol competitions for faster loads - remember your chemistry classes...heat causes gases to expand, cold caused gases to contract.

Thats all the obvious stuff I can think of.

Good luck and be safe.
 
I have enjoyed the discussion. I absolutely know that I have not screwed-up the charge, but I also know that I can likely chalk most of this off to the crimping.....that's where my suspicions lie. I recall that I did make some adjustments to my "process" on this batch and had simply tossed all these rounds in the same container with all the other rounds I had loaded with this particular charge. It's not so hard to believe that a tighter crimp will result in more pressure....I just never considered it would be that obvious, but it is.
 
I recently found this out myself. My target load for 357 is 6 grains of Unique and regular primers. I ran out of primers and the wife wanted some target loads for the next day. I loaded up a bunch with 6 grains of Unique and the Mag primers I had. They resulted in much more recoil and noise.

So yes, it makes a difference. To the OP, I don't think you need to pull anything and check the powder charge, esp since you already said you know its right.

You may want to pull them down and reduce the charge some if you don't like the extra oomph... Or just shoot 'em up (assuming you aren't seeing pressure signs.)
 
Personally I don't like shooting someone's reloads after I was given a bunch of .41 Magnums and pulled them and found a compressed load of Unique, at least 15 grains in there. I have probably 200 .38 Specials waiting to get pulled right now that I was given, I won't shoot them and will reuse the brass I like, melt down the lead bullets and drop the primers. As far as magnum vs standard, I have yet to use a magnum primer in either .38 Special or .357 Magnum. With my loads of 2400 I have had no issues and the accuracy is great. You need to check which powder burns at a rate where you would need the magnum primers.
 
Handloader magazine has had some articles lately concerning magnum primers. They contend that in some cases the loads spike way over pressure without raising the fps all that much. Some powders are more predisposed than others. I must confess that what I load doesn't get into magnum primers and small rifle primers, so I did not read as closely as I should to comment.
 
Magnum pistol primers burn slightly longer and slightly hotter than standard primers. With such a light charge of Bullseye I really have a hard time believing you can hear and feel the difference when using a magnum primer. (not that I don't believe you)

In any case I see no reason you would have to shoot light target .38 Special loads in a .357 Magnum L frame just because you used a magnum primer.

Please make up 10 of each keeping everything the same but the primers. Drop the powder at the same time, use the same die settings, same bullets and COAL and same brass. Then shoot those rounds over a chrono and you will see what we are talking about...
 
In loads that I have chronographed a magnum primer in a 38 spl std.
load with a 3-5 gr charge of fast burning powder will increase velocity
about 10 fps over a standard primer. In a 357 mag. load at much
higher pressure using a case full ( 14-15 grs ) of a slower powder like
2400 a magnum primer can increase velocity 50 fps or more over
a standard primer. I find it hard to believe that in a 38 spl plinking
load that anyone could tell the difference between primers if tested
on this.
 
snubbiefan said:
I came across some 400 primed 38-special brass cases. I have no idea how they are primed. I loaded a few up with my normal light-load for the wife and there is a LARGE disparity in both report and recoil. I used the same amount of Bullseye (2.5 grains) in each and every case under a 105-grain cast LSWC and am sure I have not double-charged a single one. I do that by hand...one case at a time and out of the 25-or-so that I fired....most were hotter than I had expected and I could not have double charged that many by accident anyway.

My ?...will just the priming with magnum primers under the exact same charge and bullet weight/design make a noticeable difference in report, recoil and power? I'm not breaking any wrist here mind you....I just noticed a decided difference between these and the ones I prime with small pistol primers.

Obviously....I have never used magnum primers before.
Click to expand...

I seriously doubt it has anything to do with the primers - especially with Bullseye which is easy to ignite.

I think you should pull down a couple and measure. Single stage reloading is the greatest cause of multi-piece take-down handguns.
 
Here is a link that Bob Hagel did a bit of time ago. It is public domain. Handloader Magazine did a article last year on the subject.

LoadData

Handloader mag is Oct/Nov 2011. Due to copy right infringement I am not allowed to post it here. I do have a .pdf of it.
 
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Been wondering about Std vs. Mag primers. Winchester Lg Pistol are for "standard or magnum loads". I've been a little hesitant to load H110 with these primers. I've had to search for small pistol magnum's to load hot 357's, but I do load milder stuff with standard primers. I'm thinking of loading some identical rounds with std and magnum primers and see what the chrono says
 
I appreciate all the comments, suggestions and general discussion folks. I generally ONLY load for the 38-special and have never actually purposely loaded any magnum primers. The small pistol primers are all I ever use, so I sought the advice from folks that had experience with the magnum primers and if it would make much of a difference. Obviously.....maybe minimal at best in terms of velocity, recoil and report.

I just simply shot-up the remaining few rounds of this "suspect" load in my 686 (which never hurt a thing) and will simply start all over again with known primers and be more careful.

I think my question has been answered.
 
dirty gary said:
Been wondering about Std vs. Mag primers. Winchester Lg Pistol are for "standard or magnum loads". I've been a little hesitant to load H110 with these primers. I've had to search for small pistol magnum's to load hot 357's, but I do load milder stuff with standard primers. I'm thinking of loading some identical rounds with std and magnum primers and see what the chrono says
Click to expand...

I've conversed over the telephone with the tech at Alliant (formerly Hercules) Powder, in Virginia.

We discussed the WLP Winchester primers which describe the usage for "standard or magnum loads."

He advised a 10% powder charge reduction (from Alliant's listed charges) when using WLP primers, because they are actually Magnum primers, and will raise CUP pressures.


FWIW: I have loaded many, many .41 and .44 magnum loads using the WLP primer & Winchester 296, (which is the exact same propellant as H110), and have had no problem with excessive pressures.

Hope this helps!
 
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