stocked up pretty well on everything else but getting to ground zero on small pistol primers. however…i do have a small supply of magnum small pistol primers was saving in case i start up w/the .357 again. can i use em in to load .40 s&w with? am loading hard cast bullets from oregon trail with blue dot, uniqie. thanks!
I would try it, but lower my load a small bit and work it up again just in case there is any difference/effect.
e-guns is correct. Higher pressure rounds especially, should be downloaded a little. Maybe 10%. A round like 45acp unless loaded ++P is probably not going to show a significant difference form standard primers. Very low pressure round. My 223 loads I have to adjust if using magnum primers. I can see a difference in pressure with them. But mag primers are safe. Download a little and test. And use common sense.
Like e-guns said, lower your powder charge a little bit and go from there.
I recently loaded some 9mm with Federal Match Magnum primers and they shot great. The powder I used was Ramshot Silhouette and lowered the charge by .2 grains.
In my research before using them there were a couple items I learned:
The primer cups may be harder and if your load is too light you may get hot gases escaping past the primer which could erode the breachface.
Small Pistol Magnum primers are only slightly hotter than regular small pistol primers but this is not true of rifle primers. Rifle magnum primers are much hotter.
In some cases, with slower burning powder, the magnum primer will help with keeping the ignition more consistent.
I haven’t found any noteworthy difference in hardness of cups between reg pistol and mag pistol. Not for pistol reloading anyway. Revolvers are a different story. Rifle primers are definately harder. Now different manufacturers cups are different hardness. Cup thickness problems are usually associated with revolvers set up for competition. Thats why you should not use pistol primers when loading for rifle. Especially in AR’s. Slam fires can result from the FP bouncing on a soft primer.
thanks guys. you all answered my question and then some!