Does new primed brass need to be resized?

[elkslayer4x5]

I posted this question over on another gun/reloadong forum, but got inclusive awnsers, so thought I see what you fellas think. I was given a partial bag of new primed brass and I know that a bag of new primed brass could be knocked around and the necks may need to have the expander ball pulled through.
While reading the basics of reloading in the Lyman 49th, I read a statemant that I should resize new brass, does that apply to new primed brass as well?

 

[NeuseRvrRat]

you got inconclusive answers because there is no right answer. some folks do. some folks don't. measure the brass and decide for yourself.

 

[Bentley4700]

I would. Remove the decapping pin and size just to make sure.

 

[kerreckt]

Look at the overall condition of the brass, measuring some of it and make a decision based on your findings. Normally, primed new brass I wouldn't resize. Unprimed new brass, I do. Rightly or wrongly I assume the brass gets resized in the priming process. So far this has served me well. I make these kinds of decisions on a case by case basis...no pun intended.

 

[Drail]

New brass will have a nasty burr on the mouth and you really should size the brass to get good case neck tension and de burr the mouths inside and out. Once the burr is cleaned up you'll never have to do it again. I always size and deburr new brass. You'll also get a more consistent crimp with the burr removed.

 

[jcwit]

For no more work that is involved in resizing, I would.

The actual answer is really up to you.

 

[gamestalker]

Again, it's a personal thing. I do because I like to start out with a consistency that only I can attest to. But you'll have to make that decision.

GS

 

[Plain Old Bill]

Easier to do it now than put up with the embarrassment of cartridges that won't chamber later.
Don't ask me how I know that.

 

[Walkalong]

I generally do, but most new brass will fit most chambers, and many people think that those of us who size new brass are touched in the head.

 

[Keeperfaith]

Im new to reloading as well, the first ammo I reloaded was 41 mag with new brass. I didn't do the resize/deprime step but I did open the case mouth (to make bullet feeding easy) and debur in and out of the case mouth just in case.

the ammo turned out great.

with a set of brass that you got some w/ primers and some without. you dont know if the person who deprimed them used a resizing die or just a universal deprimer. so it may be in your best interest to deprime/resize (save the unused primers (they will work).

my 2 cents

steve

 

[PapaG]

Just being a smarta$$ here but if it is new, it should be sized, not resized. All kidding aside, it makes sense to size, chamfer and maybe even trim new brass for the best uniformity. It varies a lot even in the same " lot " .

 

[moxie]

I size new or fired brass to make sure it's OK. What's the harm?

Re post #5, if you trim you need to chamfer and de-burr again.

 

[BBDartCA]

I had a bunch of Speer 9mm & 40 primed brass and I did not resize any of it. Cases checked out with the mic and case gauge. No issues shooting it. Did of course flare the case mouths a bit during the charging of the case.

 

[savanahsdad]

handgun or rifle ?? handgun you will be flairing and squezing back down as you load , Rifle I would just neck size and check case liength this is NEW brass right?

 

[cactus02]

size it! ammo from win and rem in bags get thrown around and deformed, you want it to be consistent so size it.

 

[mtrmn]

If it really is NEW brass, then it should be the same brass the ammo companies load without re-sizing. I would drop a large sample (20 or so out of 100) in a case gage and see how they do. If EVERY ONE meets specs in the case gage, I'd load them up. If you have even 1 rd that does not pass the case gage inspection, I'd re-size it all. Of course this assumes you already have or can easily obtain a case gage.
If it's for, say, a semi-auto pistol, revolver, or something else you can easily access the chamber on, then there's your case gage right there. I remove the bbl on my .45 and 9mm and use my barrel for the case gage.

 

[dickttx]

The most important thing is whether the case mouth has enough tension to hold the bullet properly.

 

[8mmman]

Well I've been relaoding for 50+ years and never have to date. SO I see no reason to do so unless your a match shooter..

 

[HOWARD J]

I resize my pistol brass---there is always that one that will jamb your gun & make you look not to smart.

If my new rifle brass fits good in the cartridge gage I expand the mouth before seating & I DO NOT resize.

 

[cfullgraf]

Generally, i resize new cases, rifle and pistol.

Recently, I got some new primed cases and I have not been resizing them. There have been a few with dinged necks that I have been setting aside. When I get a bunch or feel like spending the time, i will resize these cases.

Generally, I do not like new primed cases.

 

[Drail]

The problem is that some brass has a nasty burr left on it and it can flake off and end up in your dies (you'd be amazed at what is inside your dies- I have seen tiny brass rings compacted against the crimp shoulder of the crimp die) or inside your barrel. Most brass isn't this bad but over the years I've bought a lot that had huge burrs on the case mouths. Look at any new brass real hard.

 

[murf]

get out your calipers and measure a few necks. with a bit of math and the rim thickness, you can determine if the bullet will have enough case neck tension. measure twice @90 degrees out to see if the mouth is round or egg-shaped. measure the case length while you're at it.

if egg-shaped, dinged or dented, then resize,trim and chamfer.

all brass is not created equal!

murf

 

[elkslayer4x5]

It was a left-over bag of New, Primed, Winchester .270 Win cases. A few had dings in the neck, they all checked for length. Pulled the decapping pin and neck sized 'em, pulled the expander ball through to iron out the dings, and they all chamber. Thanks for your help.

 

[ADKWOODSMAN]

I've done both over the years. I never do new unprimed pistol brass from major suppliers.
I always neck size rifles cases so there is the same pull when they are fired. This is my 2 cents.
RDH