magnum large rifle primers vs large rifle primers

[.357]

I've been reloading handgun for 5 or so years (not bad for a 26 year old with anti gun parents) however i am going to start loading for rifles. ( the savage 99 and a stevens 223, and eventually a very old 38-55) however the only primers i can find are some my neighbor gave me that are magnum large rifle primers, now the magnum gives me pause and i've heard various things from: dont' use them in an old gun to use them just 10% dialed back on the powder from a regular large rifle primer. So tell me oh great cast boolits readers, what should i do?:???:

[MtGun44]

Depending on the particular powder you may see no difference at all. If you are
loading normal rifle loads with normal rifle powders, the 10% rule would seem
prudent and you will likely find that you can safely work back up to close to or
even right at normal loads safely, esp with ball powders which are often a bit
harder to light.

I would be very careful shooting any of the cast boolit loads that use small quantities
of fast pistol powders like Red Dot or W231 or maybe even 2400 and Unique. I wonder
if you might get these very small quantities of powder to light and burn faster than
normal with a magnum primer and get a pressure spike. I would guess this is unlikely,
but being careful is a lot better than being injured or being sorry you damaged or
destroyed a nice rifle.

Bill

[725]

It's boring advice, but here goes. Follow the load manual. Some powders call for mag primers, some don't. Mag primers are advantagous in certain low temp applications. When in doubt, get your info from a manual or directly from the manufacturer. MtGun44 is giving good advice. Be careful and don't hurt yourself or those standing near you, and don't damage your gear.

[atr]

in rifle loads I dial back 5%....but I would concur with the others here that dialing back 10% is prudent

in pistols,,,,using 2400 powder I am loading at the very low end of the powder charge when using mag pistol primers

[WARD O]

If you are using BP or a BP substitute in that 38-55 then some would say that the mag primers are preferred.
A general rule is that most ball powders do better with mag primers while other powders do not require mag primers unless you are loading large volume cases. But if that's all you got then go ahead and use them but work up the load like you always should.

Ward

[Hunter 24095]

I use mag rifle primers and H-380 in one of my 22-250 loads and it is very accurate with no signs of pressure but I did start low and worked my way up.

[FromTheWoods]

Yup, I use H380 for my .270. The manual calls for a magnum primer with this powder. But, I'm shooting jacketed, not cast in this round.

[jlchucker]

I've been handloading since the 1970's and have yet to buy a single 100-pack of magnum primers. I use Winchester large rifle primers pretty much exclusively--or CCI if I can't get Winchester. I've never had a problem with either one. Let me say that my loading is pretty much confined to standard calibers, though--no exotic magnums.

[felix]

In general, only the Winchester RIFLE Magnum primer is of your "dangerous" concern. Do not use them unless your case size is 2.5 inches or longer and using a case full of powder. ... felix

[Heavy lead]

In general, only the Winchester RIFLE Magnum primer is of your "dangerous" concern. Do not use them unless your case size is 2.5 inches or longer and using a case full of powder. ... felix

I reserve my WLRM's for the 416 Rigby, 338 Ultra Mags and the 7 UM when I shot it, or a case full of slow ball powder like AA8700, they make a Fed 215 seem cool.

[Uncle R.]

In general, only the Winchester RIFLE Magnum primer is of your "dangerous" concern. Do not use them unless your case size is 2.5 inches or longer and using a case full of powder. ... felix

Felix - would you mind explaining on that a little? I'm trying to learn here too. Are the Winchester rifle magnums hotter than other magnums? More brisance? Do they supposedly start the bullet before powder ignition with risk of SEE if the case or charge is too small?
I always thought that the Federal 215s were supposed to be the "incendiary grenade" of large rifle primers - first time I've heard warnings about the Winchesters. Then again, I've often fallen behind the times in matters like this.
<
:-?
Thanks:
Uncle R.

[runfiverun]

win uses aluminum styphnate and it spits out like a sparkler.
federal uses lead styphnate it burns longer not really hotter.
with the win you have a chance of it igniting too much powder all at once.
i do use win lr mags in my 30-30 with nearly a case full of ball powder.
i have used it with 27 grs of aa2230 in the 30-30 and can feel the difference in recoil over the standard primer.

[felix]

Correct. SEE conditions go up rapidly with Winchester Magnum Rifle because they produce extreme force when compared to any other primer. Heat is what is required with zero force (not possible to date) when the cases are pistol size. ... felix

[Uncle R.]

Thanks for the explanations guys. One more thing to tuck away in my cluttered mental file cabinet.
:roll:

[Ron.D]

This last piece of info gives me cause for concern. I just started loading my 358 Win. with WC820. The starting loads are just under 50% capacity, so I thought I'd use a mag. primer. The ones I used are Win. LR Magnum. I won't be going to the range for about a week. I'd appreciate any input some of you may have on the subject, especially Felix. Thanks. Ron.

[felix]

Ron, your combo is not COOL! 50 percent capacity would be about 25 grains, right? At best your ES (velocity/pressure difference between shots) would be excessive. At worse a SEE condition is fairly well set up. I am assuming your primer supply is non-existent and that you don't have a proper supply of powders. Pull the rounds, Ron. ... felix

[Ron.D]

Thanks Felix, I'll do just that. I do believe WC820 can be safely used but I value all my digits and eyes even more. Thanks for the headsup, esp on the primers. I do have other primers, but have more of the WLRM and I wanted to use the mag. I also have FED LRM. I will be pulling them. Ron.

[.357]

Thanks for all the info guys. I traded the primers for "stuff" at the local gun show and managed to find some remnington large rifles. The savage 99 is happy :D