New Brass Sizing ?

[buyobuyo]

I've bought some new brass (10mm auto) for the first time. I usually just buy once fired brass, but I got a smoking deal. Just curious what the consensus is on if you size the brass before loading or just go straight to flaring and seating?

[country gent]

I size to make sure its to size and correct. Ive gotten bras that was new unprimed that was tight

[PJEagle]

Others opinions will vary, but I always size and trim new brass before loading. You may never need to trim again.

[M-Tecs]

It depends on application and the brass. Bottleneck new case always get sized. Straight wall cases may or may not have enough neck tension without sizing. A while back I ordered 2K of new 45 Colt Winchester brand brass. On about half the bullets would drop about halfway into the case. I was loading them for SASS matches that require very low accuracy levels, so I had not planned on sizing them.

[Baltimoreed]

Always resize new brass. Irons out any dents and makes them all uniform. Plus it gives you a chance to inspect them for damage or missing flash holes. Quality control isn’t what it once was.

[nicholst55]

I've seen too much new brass that had out-of-round case mouths. It all get sized before loading.

[Winger Ed.]

I do. I'm not sure why, but both times I had to buy new brass, I sized it.
Back in my .50BMG days, I bought a lot of GI pull down.
I sized it too.

[dtknowles]

I have not had to size the new brass I have purchased, one cartridge I shoot, 6mm PPC, I did turn the necks and neck size. I have had to straighten some case mouths but I did not size them. I don't know how many you have or plan to load at one go but If I had 500 or 1000 pieces and am working up a new load, I would load a box (20 or 50) with starting loads without sizing and see how it goes. If I had a progressive press already set up to load a proven load, I would just dump them in the hopper and crank away.

Tim

[Bazoo]

Most of the time when working with new brass I size it. Anything that gets a roll crimp also gets trimmed.

[stubshaft]

I resize new brass too, just to ensure that there are no flaws.

[poppy42]

I size new brass. As for trimming, I’ve never trimmed pistol brass in my life! Unless ya wanna count making 9x18 from 9x19 by trimming a mm off. Revolver, 38, 357 mag and 357 max, that’s another story. Same with bottle neck. Measure, trim if needed.

[redhawk0]

I always size new brass. It takes a lousy 15 min/100...so why not. That's 15 more minutes I get to relax in the shop. I've gotten new brass that has been dinged up/out of round, so for me, its just worth the time.

redhawk

[Outer Rondacker]

Ill share I'm not scared. I have only ever had brand new brass once. About 8-10 years ago guys on the forum where getting into the big bore AR platforms. I jumped on the wagon. A Beowulf. Well it was fairly new and brass was none existent. So I ordered up 200 new from some place. It showed up and I didn't even think about it at the time. I grabbed a hand primer and popped 10 primers in. Dropped some powder and tossed in some 325g projectiles I load 50AE with. Grabbed the gun and a mag and hit the range. OMG I never considered the brass was not sized to spec. I called the barrel maker even sent the upper to be checked. Still not thinking about sizing. They said they polished the throat and chamber but it ran fine for them. They even sent me a box of ammo and a few extra mags for the so called issue I was having. Well pumped factory 10 rounds down the pipe and ran like a top. Came home sized the empty brass and loaded them up. Also grabbed the 4 remaining rounds that was reloaded with the new brass and hit the range again. What is going on once again the new brass loads would not run. Then a light bulb went off. OMG you fool size the new brass. Guess what, works fine now. So that is my story. A guy who has reloaded garbage pails full of ammo for about 35 years had a brain fart. Size all brass new to you end of sentence. Save the headache. I hope my stupidity helps others out.

[buyobuyo]

Thanks all for the comments. Definitely unanimous on sizing, and it makes sense.

[Stew]

When I was new to reloading, I had experienced new cases that the bullet would drop right through the mouth into the case, both straight wall and bottle neck. Ever since I make it a practice to FL size all of my new brass, and check/trim length.

[45_Colt]

A little lube and/or vibratory tumbling is also recommended on new brass. It is very 'dry' as supplied due to the solvent rinses. This is true even with carbide dies.

45_Colt

[challenger_i]

Years back, I bought a bag of Name Brand pistol brass. Loaded it straight out of the bag. Every darn one of them, the bullet would twist in the case with ease. Never again.

[georgerkahn]

I've bought some new brass (10mm auto) for the first time. I usually just buy once fired brass, but I got a smoking deal. Just curious what the consensus is on if you size the brass before loading or just go straight to flaring and seating?

I, too, have/love the 10mm Auto calibre, as a btw . Germaine to your question, my experience many different brands of brass are -- albeit produced to SAAMI standards -- a tad different -- 'specially vis length. I'm OCD re case length, so ALL brass I acquire -- brand new or fired -- first gets primers removed if fired; then gets wet tumbled; and then goes through sizing die! After, each and every case gets a go-through in my L. E. Wilson case trimmer. I cannot count on my fingers the number of occasions where brand new brass -- after sizing -- is a different oal length than, say, others!
It does not take very much time at all to do this -- but it guarantees me all my brass is the same size and length for loading.
geo

[Wheelguns 1961]

I picked up some brand new Starline brass in 45 colt years ago. I started measuring it, and the length was all over the place. I decided to size it, and guess what, after sizing they all measured the same. All brass whether new or used gets sized first in my house. I have had the same thing happen with Starline 327 fed mag brass also.

[Shawlerbrook]

I also size just to be sure..