Use of magnum primers in non magnum loads.

[eagle24]

This is probably a dumb question that I should know the answer to since I have been reloading for 25 yrs. Here goes anyway: I've been loading full house .44mag and also some .44sp loads the last few days. I have run out of large pistol primers, but have plenty of large magnum pistol primers. Is there any reason not to use large magnum pistol primers in low powered plinking loads? I would guess that they might have an effect on accuracy, but is there anything that might present a danger. Also, I have always wondered about using .38sp data and .44sp data for loading in .357 mag and .44 mag cases respectively. Are there any concerns there since the volume of the combustion chamber is different?

 

[The Bushmaster]

Lower your powder charge and start over. Work up until you reach what you want or you start seeing over pressure signs. A chronograph is very helpful in this situation...As far as your last question...I have never done that and have had no reason to do so although I have both .38 special and .357 magnum

 

[pbhome71]

Also, I have always wondered about using .38sp data and .44sp data for loading in .357 mag and .44 mag cases respectively. Are there any concerns there since the volume of the combustion chamber is different?

I do use 38special data in 357 case. I believe that it will have even a bit lower presser than loading in a 38 special case.

I use this for plinking lead load. No problem with it. The only concern is loading too low and have a stuck bullet.

-Pat

 

[Steve C]

If your load is already at a start level or below for a magnum round the use of mag primers will pose no danger. You may get a slightly higher velocity with the mag primers but it sounds like you're running them slow already.

 

[Rico567]

If you're not following published commercial data for magnum primers, then the same rule of thumb applies as for all reloading: whenever you change a component, back off on the powder charge and work up.

 

[eagle24]

Lower your powder charge and start over. Work up until you reach what you want or you start seeing over pressure signs.

Actually, I'm talking about using mag primers in special loads, so I'm not going to see any signs of excessive pressures. I guess I was wondering if there were any weird phenomenons that might occur with using mag primers in light loads. Kinda like the warning not to load reduced charges with H-110. The guns that I will shoot them in are mag chambered guns.

I prefer to use the mag cases for special loads in my mag guns. It keeps the cylinder cleaner, which in turn keeps the mag cases cleaner. Lots of times I will wipe the cases while they are warm and only tumble them every other or every third loading. Plus I've got tons of mag cases.

What has always been strange to me is why in loading manuals the data for cast bullets is always so high for mag chambering ammo. For instance, If you look at a 44 sp load for 240gr wadcutter using unique powder it may show a.a gr to b.b gr for the powder charge. If you look at the 44 mag data for the same powder and bullet. It starts much higher c.c gr to d.d gr. There is a significant gap between the two. It would seem logical that you could actually load any powder charge between the minimum charge for the special load and the maximum charge for the magnum load, if you are using a magnum case. Many of my plinking loads fall between the data for special and magnum. I don't like to shoot cast lead bullets at magnum velocity on a regular basis because of leading. I do have some cast bullet hunting loads that I prefer over jhp that I load at higher velocities.