Light 38 Special Loads, . . . Using Magnum Primers?

[Jeff R]

I have been enjoying some success shooting 148 gr. wadcutters, and 158 gr. and 177 gr. LSWC Boolits, using light charges of Unique, Titegroup, Bullseye and 231. I am using .38 Sp. wadcutter brass, and the loads are basically the starting loads from the manuals.

I am going through Small Pistol Primers like crazy. There are plenty on the shelves at the local gun store, so getting more is not a problem. I have a pretty big inventory of Small Pistol Magnum Primers. I don't think I will be shooting many loads that call for the use of a magnum primer.

I would like to use up a bunch of these magnum primers. To use them in the light loads described above, what problems might I encounter? I don't want the accuracy to degrade, (or safety) just for the sake of using up some of my magnum primer stash. Your opinions will be appreciated.

Thank You!
Jeff

[bangerjim]

For me....during the "primer shortage of olde", I used mags in standards by just backing off the load by 10%. Worked for me.

I even use mag primers with NO powder to shoot hot melt glue boolits in every pistol cal I load. They have a tad more kick it seems like.

Now I have tons of standard AND magnum primers so I do not worry about swapping.

banger

[Outpost75]

I use small pistol magnum primers in .38 wadcutters all the time and with Bullseye powder a charge reduction of 0.2-0.3 grain gives the same velocity as a standard primer. If you substitute a magnum primer without adjusting the charge, expect +30-40 fps, which is not dangerous as long as you stay off the maxloads. In my match guns accuracy was not affected.

[tazman]

Since you are using light loads I doubt you will even notice the difference. Your accuracy may even improve slightly due to better powder ignition.

[jcren]

Use them all the time in 38 and 380. Just back off max load data.

[FergusonTO35]

Yep, I concur with all the above. Have used them many times in 9mm and .38 Special.

[44man]

No problems. The difference in SP primers is not great and both work fine.

[Jeff R]

TAZMAN WROTE:


Since you are using light loads I doubt you will even notice the difference. Your accuracy may even improve slightly due to better powder ignition.

I got around to doing a test. Although the test was not scientific, I can conclude that the accuracy was slightly improved, in this particular load, using Magnum primers. Everything was identical, except for the primers. The boolit was a 148 gr. BBWC over 3.0 gr. of 231. The group on the left used WSP primers, and the one on the right used CCI 550 magnum primers. I used my 6" Barrel GP100, shooting offhand at 10 yards.
Thanks for all the good advice!
Jeff
163517

[tazman]

I had that same thing happen with a 9mm load I had been shooting. The magnum primer tightened the group about 25%.

[Outpost75]

I have actually used them in .32 ACP! In very tiny cases you need to be a bit careful as you approach maximum charges, but I have found that 1.8 grains of Alliant Bullseye with Accurate 31-087T gives the same velocity with magnum primers that 2 grains does with standard, and the loads are safe and accurate in my Beretta 3032 Tomcat, Walther PP and Beretta Puma.

[Low Budget Shooter]

I had that same question brewing in my mind. Thanks for all that good info, fellars.

[tazman]

Another reason to be interested is that magnum primers come on sale more often than standard primers do, often at a better price. Midway currently has a sale on small pistol magnum primers at a very good price. You may want to get your stock caught up or a little ahead.

[Groo]

Groo here
Mag primers seem to work better with Trailboss also.

[DrCaveman]

Interesting thread. I've been saving my magnum primers for 357 loads, using the WSP for 38 and 9mm. Thing is, they are same price and basically same availability for me. Perhaps it is time to switch my buying to more WMSP. Seems to be a pretty good pool of experience here. I will definitely be trying some magnums in my next 38 spl reloading session