Large or Small primer

[Dave454]

Hello all, I hoping someone can help me, I'm new to reloading, not sure what size primer to use. I will be reloading .357 mag and .40 s&w . Primers seem to come large or small for pistol. What calibers are considered large and witch are small. I tried "Googling" for an answer but no luck.

Thanks in advance

Dave

 

[Brian Williams]

If you do not already have one, get one, A reloading manual. Most folks recommend 2, also get the book ABCs of reloading or Modern reloading or something like that.
Then read them and not just the load or round you have a mind to reload.

You would need small pistol primers for both, no need for magnum pistol primers in the 357 if you are just reloading plinkers or lightweight loads.that

 

[Brian Williams]

OH! and welcome to THR

 

[skipjack]

Dave, you should be able to see which primer to use on your reloading data page. Any good reloading data will include the primer used in developing a particular load.

It may not always specify the exact brand, but changing from one brand to another can also effect pressure. To be safe, any change in primer brand (where specified) should be accompanied by a reduction in powder.
You can work up to the specific load, checking for excess pressure as you go.

I hope this helps!

 

[griz]

The 40 and 357 mag both take small pistol primers. Make sure you get pistol primers, rifle primers are are the same size (small & large) but are hotter than you want for pistols. Depending on the powder you use for the 357, you might want small pistol magnum primers.

 

[Doug b]

Dave, Griz has got it right on the .357 rem. alliant powders light off well enough with small pistol primer, mag. prime is counter productive with alliant.Don't know about the .40 S&W only loaded a few hundred but they do indeed use small pistol.Welcome aboard.

 

[Encoreman]

Hi Dave, Welcome to THR. I will give info that I've learned about primers. I assumed that all small pistol primers were the same. Wrong!! I have found that Federal primers are softer and easier to ignite, eliminating most misfires. This is especially handy when using lighter springs in pistol or when using revolvers. I started out loading with CCI, btw they are the hardest material and harder to ignite. In rifles I use Federal or Winchester. Good Luck, read the books, double check all data, double check your scale, don't load when you are distracted, tired, in a hurry etc. Be careful and this is safer than mowing the grass.

 

[redneck2]

WHOOAAAA!!! Dude...if you don't know which size primers to use, you're WAY too early on the learning curve to start stuffing cases.

ditto on buying 2 manuals. Read and re-read. You've got two of the highest pressure rounds (least forgiving) that are available. Just something like seating the bullets a few thousands too deep on these rounds can make dangerous pressures.

Go slow and ask questions. HTH

 

[Ares45]

WHOOAAAA!!!

2nd.

Please, for your own well being, get a couple reloading manuals and read them cover to cover. .40S&W & .357Mag are big bad boys when it comes to chamber pressures. Attention to detail is required in masse with these two. Welcome to the boards. Enjoy.

 

[Dave454]

Thanks for all the help and advice I will definitely order a couple of books and read up before I start reloading.

Thanks again

Dave

 

[Run&Shoot]

+1 on the Whoooaa.

Now that you are reading manuals, the answer is: .40 S&W uses small pistol primers, non-magnum. The .357 uses small pistol primers. Magnum only if using full house loads of very slow pistol powders such as 2400, H110, Win292, etc. For Hp38, Unique, Red Dot, Win 231, AA5, etc. just use the regular primers. Only use magnum primers if the load data specifies it.

I would recommend Lee and Lyman as the best starters because they give the most complete cartridge info. Also get one from the manufacturer of the powder you choose: Accurate, Hodgdon, Alliant, Winchester. Speer is good but gives the tested OAL but not the max OAL. I don't think Nosler even gives the tested OAL.

When you get them read the sections prior to the load tables. They explain everything and you will enjoy reloading more than ever. Be smart, be safe.