small mag pistol primers

gsfxst

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I have a new can of Winchester 231.I would like to us it for 357.mag. some of the loads call for magnum small pistol primers. I don't have any mag primers .is there a danger in using standard primers.
 
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I've never used magnum primers in my 357 loads using fast or medium burning powders. I have heard that magnum primers may have a small benefit in terms of igniting fast powders in the longer cartridge, but they are not required. For slow powders like AA#9, HS-6, H-110/W-296, magnum primers are a must.
 
I wouldn’t (and didn’t) use magnum primers. I shot tons of 158 grain lead RN and SWCs with 6.5 of 231. Great load at about 1,000 fps, so not a full magnum load.
 
I think the general consensus is that magnum primers should be used with ball powder. I use std primers in all my 357 and 30 carbine loads with 2400, which isn't a ball powder.

I think W231 is a ball powder so maybe that's why some manuals call for mag primers.

Personally I don't think I've ever heard of anyone using std primers having any problems with W231 to load .357.
 
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There is no need for a magnum primer with 231 in a .357, IMHO - or at least I have never seen or heard of a need. I wonder if they didn’t specify it just because they used the same primer for everything else in their .357 data? I have been using 231 with Federal 100 primers in moderate .357 loads for years, if not decades. Never saw any indication that made me think a magnum primer might offer an improvement.
 
In my limited experience, I have loaded tons of 41 Mag with 20 grains of H110 and standard primers with absolutely no ill effects and any velocity difference was not noticeable. In theory you may have some unburnt powder but I haven't personally experienced that with H110. Of course other's experiences will vary but for sure, you won't be doing something unsafe.
 
231 has been one of the fastest powders made. Hard to believe someone would print loading data recommending a mag primer.

Most reloading manuals will recommend a magnum primer for magnum cartridges no matter which powder they list.

OP,
As said above, W231 does not need a magnum primer to ignite correctly. Now W296 is a different story, a magnum primer works much better. No danger at all.
 
In my limited experience, I have loaded tons of 41 Mag with 20 grains of H110 and standard primers with absolutely no ill effects and any velocity difference was not noticeable. In theory you may have some unburnt powder but I haven't personally experienced that with H110. Of course other's experiences will vary but for sure, you won't be doing something unsafe.

Hard to understand why you would want to use std primers with H110. Nowhere in any load manual or magazine article will you see std primers recommended with H110/296. Depending on your bullet and the length of your gun barrel you are probably only getting around 1050-1100 FPS out of your 41 “magnum” load. You don’t notice any velocity loss for one reason, you don’t have a chronograph. You could use 9.5-10 grs of Longshot or Autocomp and save 50% on powder cost. OR...get some magnum primers and get magnum velocity.
 
In my limited experience, I have loaded tons of 41 Mag with 20 grains of H110 and standard primers with absolutely no ill effects and any velocity difference was not noticeable. In theory you may have some unburnt powder but I haven't personally experienced that with H110. Of course other's experiences will vary but for sure, you won't be doing something unsafe.

The unburnt powder gets blown out of the gun and ends up on the ground. That's why you haven't seen it. Like one of the other posters said, if you chronograph that load you will see a big difference with the magnum primers. I agree that it's not unsafe but it is very inefficient.
 
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If you have any winchester standard primers......

they were designed for "Ball powder" and run a little hotter than the other standard primers, so that they will work with the companies powders.

I also used their magnum primers but find that they were not needed with my loads and weapons
to gain any advantage in my loads and powders use over the years of testing.

However, a magnum primer with ball powder is not a bad idea, to get 100% burn and maybe a cleaner shooting table
if you use the very slow burning powders, if using the other brand primers.
 
Just to further the discussion, I shot a bunch o non-canister equivalent to Accurate #9 in a wildcat based on the 357 Mag case tapered to .319. It used lead bullets fired just subsonic from a custom single shot bench gun. My primers of preference were Federal SR Match. This combination shot cleanly and accurately in my rifle, but this discussion got me wondering about the relative strength of these primers vs the others under discussion.

Froggie
 
Just to further the discussion, I shot a bunch o non-canister equivalent to Accurate #9 in a wildcat based on the 357 Mag case tapered to .319. It used lead bullets fired just subsonic from a custom single shot bench gun. My primers of preference were Federal SR Match. This combination shot cleanly and accurately in my rifle, but this discussion got me wondering about the relative strength of these primers vs the others under discussion.

Froggie

If it ain't broke, don't fix it. ;)
 
I thought at one time the...........

Thread Index

had a fact sheet with the different primers and their properties

from cool to hottest flame ?

Later.
 
Plain and simple, Ball Type Powder. Reliable consistent ignition across the entire spectrum.

Look at any older Speer manual and you'll see their test commonly use magnum primers with non magnum calibers using BTP's. Speer testing shows some combos even low pressure low velocity loads using BTP's are more consistent with magnum primers.

Do I use magnum primers with HP38/W231? Rarely, if ever but I know why some data recommends it.

Especially in rifle loads, I use magnum primers more often than not now. Even though I use a lot of extruded like IMR4064, 4350, 4831, I like W760/H414, W748, H335, Accurate 2520 etc, and it's easier to keep one type primer on hand. I still test accuracy using test both standard and magnum, if there's little to no difference I generally use the magnum large rifle to work up my loads.
 
I have a new can of Winchester 231.I would like to us it for 357.mag. some of the loads call for magnum small pistol primers. I don't have any mag primers .is there a danger in using standard primers.
There is a lot of information out there regarding the use of small rifle primers in place of small pistol magnums. For CCI at least, the two appear to be the same product in a different package.

This is not a recommendation, just a possible avenue to research.
 
This video is well worth watching if considering interchanging primers when reloading. Facts over opinion is the only way to go.

[ame]https://www.youtube.com/watch?v=NGVRGsoOr6k[/ame]
 
This video is well worth watching if considering interchanging primers when reloading. Facts over opinion is the only way to go.
Absolutely, and to further put a point on it, CCI has a BYOP (bring your own primers) program where you supply the primers and they make factory reloads for you. They will load your ammo with SPP, SMP, or SRP primers for you - whatever you have to give them.
That means they are accepting the liability of loading ammo with the "wrong" primers. Think they'd do that if there was ANY appreciable difference? Obviously the answer is a big NO WAY.
 
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