Resizing

[hughie]

Newb question. When you resize bottle neck brass do you do full length of just neck. Also, how often do youtrim the case.

 

[Mauser lover]

It depends.
What was your brass fired in?
What do you want to fire your reloads in?

Let us say that somebody is shooting his only bottlenecked rifle, a .308 Remington 700. He regularly shoots out to 12000 yards. He always uses brass he fired, and he only shoots it in that one gun. He probably wants to only neck size. It is theoretically more accurate (practically, I don't know that I am convinced). I do it because I don't have to lube the cases!

Somebody else has a .308 Remington 700, but also a M14 (.308) and an AR-10 (.308). He either neck sizes but keeps the brass from the different guns, and the reloads for the different guns separate, or he full length sizes. (or he has feeding problems)

The advantage (theoretical at least) for neck sizing has already been mentioned.

The advantage for full length sizing is that it will now feed (hopefully) in any firearm of that chambering. If the first guy gets someone else's brass from the range, he will need to full length size it, then shoot it, then neck size it. Every chamber is slightly different. When you shoot a firearm, the cartridge case forms to the exact dimension of that firearm's chamber. That firearm's chamber is not quite the exact same size as a different firearm's chamber. They will both accept factory, or full length resized cases, but will fire form brass differently. (I learned this the hard way, tried range brass in my gun without sizing, couldn't extract it)

Personally, I trim the brass every reload. You don't need to, but I feel like it, so I do it.

 

[hughie]

loading for one bolt action gun

 

[Mauser lover]

Then I would neck size only, except brass acquired from somebody else, range pick-ups, or gifts from a friend who doesn't reload. Those would have to be full length sized the first time you reload them.

 

[gamestalker]

If you neck size, you'll also have to FL size intermittently to reposition the shoulders, (Bump). The shoulders will eventually get pushed so far forward that the bolt will either not close, or you'll gall the lugs trying. This is also referred to as head spacing the brass to the chamber.

In the bolt guns I neck size, it is almost a waste of time doing so because I rarely get more than a couple of necking's before I have to bump the shoulders back .002". But even so, it's worth it to get a few more uses off the brass by necking when I can.

GS

 

[beatledog7]

Neck size only is for brass that were fired in the exact same bolt action or single-shot rifle for which they are being reloaded. Even then you much test chamber the brass to make sure they will chamber properly.

Trimming is required for bottleneck brass that is over length after sizing.

Yes, it's really that simple.

 

[stubbicatt]

Depends on your goal, I guess. If you don't like lubing up the cases and cleaning them off afterwards, then your goal is met by neck sizing. If you want reliable ammunition, that will chamber readily in your firearm, then FL sizing is likely your approach. If you want to load really accurate, really reliable ammo, then (among other things) you FL size after neck turning and you use a bushing type die to accomplish this, one cut to mimic your chamber.

Some guys are body sizing and then neck sizing thru either a bushing or a Lee mandrel type neck sizer. I have seen claims lf minimal runout using this technique, which if yours is an accurate rifle to begin with, will likely improve accuracy a measurable amount.

 

[USSR]

Some guys are body sizing and then neck sizing thru either a bushing or a Lee mandrel type neck sizer.

That's how I do it. I use the body die to bump the shoulder back a minimal amount, and then neck size with a bushing die to get the exact amount of neck tension I want.

Don

 

[Sunray]

"...full length or just neck..." All new brass needs to be FL resized, checked for length, trimmed as required and chamfered and deburred. Fired brass can be FL or neck sized. As mentioned, neck sizing is only done if it will be fired out of the same bolt action or single shot rifle.
Trimming is done only when the case needs it. So you ned to check the lengths regularly. Not necessarily every time though.