Is it best to re-size new brass.

You need to at least run the expander through the neck to get the dents out.
I usually size and expand the upper half of the neck only. This rounds up the neck, gets rid of dents and irons the tumbling ridge on the case mouth to the outside so it can be removed.

I do not size the rest of the case nor do I trim it.

quote:

I usually size and expand the upper half of the neck only

Same here. There is usually no need for lubricant using a conventional die for this, but I like to use a Lee Collet die if available for the caliber. In addition, new brass needs to be checked for length and anything which exceeds about five one-thousandths of the mean should be trimmed back to a uniform length. Whether the cases require trimming or not, I chamfer the insides of the necks in order to assure smooth bullet seating without scraping copper from the bearing surface of the bullet.

Same

Same here except I make sure the case mouths are square and I bevel the inside edge of the mouth. I also check for centered primer flash holes first off.

Many thanks for the advice. Out of interest will seating the bullet not take the dinks and dents out of the neck.Perhaps I should have said in my first question this is new .308 laupa brass loaded with 43.5 gr varget and 168 gr a max.

Unless it is badly dented it will. The problem is that it will also shave the bullet and that is not so good for very accurate ammo.

This is just my own way, and probbably no one else does it this way anymore, but here it is.

I do not expand the necks or trim them to length before the first firing IF I am loading boat-tailed bullets.

I always trim the cases for length after the first firing has fire-formed them to the chamber, regardless of bullet shape.

If I am using flat-based bullets, I do expand the case necks before they are loaded the first time.

1. The only new brass I size before loading is 460 S&W Magnum brass and that's only because if I don't, the bullets move under recoil.

2. I don't trim new brass.

3. I don't try to get dents out of new cases unless they're pretty severe and interfere with bullet seating or chambering.

4. I chamfer the mouths of new brass cases if I'm to be seating something other than a boat tailed bullet. Some flat based bullets have a small radius at the periphery and I don't usually need to chamfer case mouths to seat those bullets.

5. I do check for eccentric flash holes. I find a problem with flash hole centering is very rare in commercial cases but common in older Lake City military brass.

I only debur the flash hole on the first loading....then after a fire form its trim, and chamfer time

Except to round out the neck and chamfer the inside of the neck, I don't do anything until after the first firing. I agree with AC that if you're using BT bullets even that isn't needed but I mostly use flat based bullets so......
Some folks have posted that new brass would not fit in their chamber until it had been F/L resized. I've never found that to be the case with any I've bought but it might not hurt to drop a couple into the chamber to make sure that they'll go into battery.

After having an experience several years ago of bullets moving in new, un-sized 375 H&H brass, I size everything!

Many thanks for the info. Its always interesting to hear how other folk do it.

quote:

Originally posted by Rusty:
After having an experience several years ago of bullets moving in new, un-sized 375 H&H brass, I size everything!

+1, I've seen this in to many different cartridges, there is no uniformity.

I do it the same way as Alberta Canuck if I am using Lapua brass. If using win or rem brass some of the case necks are dented to much. so then I will neck size.

BigB

For good or Ill I Size all new brass...


Then I fully prep it


Snake