Resizing new brass?

[chrisliee]

I have purchased new brass a few times and it just dawned on me that I did not resize it because I did not need to remove the primer. Should new brass be sized? I just resized 200 new 9mm cases. Did I waste my time?
I figured better safe than sorry. I have fired about 100 .45 rounds that were not resized, and they seemed fine.
I searched my reloading book and so far haven't found anything about resizing new brass. Seems there is always something new to learn about reloading.

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[HollisOR]

It is usually a good idea to resize new brass. I have a progressive press so it is not a extra step. As you found out, depending on your firearm and who ever made your brass manufacturing techniques/QC included, it may not have to be done.

 

[Throckmorton]

I tried loading new brass one time without sizing it 1st...some of the bullets all but fell into the mouth of the case.I now size all new brass.Easy for me since I too run a prgressive,but even when I had the single stage,I'd size new stuff as well.
one thing I"ve learned along the way..I keep a tub of hornady case lube hand and put just a smidge on every 10th case,makes sizing even small pistol brass much much easier .

 

[evltwn]

Not only should you resize, but you should also consider reaming out the flash hole from the inside of the case to remove that bit of brass that often lingers as a result of the manufacturing process. I also make the primer pocket uniform, but then I shoot bench rest, and enjoy those tight groups (if my eyes co-operate).

 

[Nwcid]

On pistol I don't think it as big of a deal but not a bad idea. On rifle it all gets the full process to they can be as uniform as possible.

 

[Translator]

I tried loading new brass one time without sizing it 1st...some of the bullets all but fell into the mouth of the case.I now size all new brass.

This is my experience with the one set of new brass, .38 Spl, I have reloaded so far.

 

[chrisliee]

Now I have 150 .40 brass to resize that already has primers. That's no big deal though. I sleep better if I reload properly and that usually means the hard way, not the easy way.
That is a good idea to check the primer pockets. I have no doubt that some brass just might be left to restrict that pocket area in some way. Just might have about 100 primered .45 brass that needs some sizing also. Do it right the first time and you only do it once.

 

[varmiter]

I have had to neck factory rem. rifle brass and I also do debur the flashhole

 

[chrisliee]

Finally received an answer from RCBS. They said new brass doesn't need to be resized, but they recommend you resize it to make sure the cases are uniform.

 

[Mark W.]

it can also depend on the chamber in your firearm. Some revolvers like the Ruger Blackhawk in .30M1 are known for tight cylinders so it might benifit from new brass being resized more then a firearm that is known to have a looser chamber.

On rifle brass I always resize it full lenght the first time I use it whiether it be once fired or new after that since my brass is assigned to a specific rifle and to a specific type of load (plinking, hunting, military repop, etc.) so except for the tapered cases I only neck size (after softening) the brass. Helps cut down on the wear and tear of reloading brass 3-5 times. Since the case is fired into the chamber it will be returning to.

With experiance you will know what is best for your own combo's.