I have shot probably hundreds of thousands of rounds of pistol ammo, and reloaded a lot of it too. But if you only shoot pistol ammo, you do not really need to be concerned about the brass stretching and getting too long. But with bottle-necked rifle ammo, this is a different story.

When bottle-necked rifle rounds are fired, the brass tends to stretch and the brass gets a little longer each time it is shot and resized and reloaded. Eventually, the brass could get so long that the neck of the brass will reach all the way forward until it can reach the beginning of the rifling. If it does this, it can "pinch" the bullet in the case and cause very high pressures and even case or primer failure.

Therefore, bottle-necked rifle brass must be trimmed to a safe length.

How do we know when this is needed? That is easy. We refer to a chart that lists maximum and minimum case lengths and use a micrometer to measure the length of our cases.

Today, I had some .30-06 brass to reload. I started off by neck-sizing the brass and de-priming it. Then I checked the length.

The chart shows the maximum length to be 2.494 inches and the "trim to" length to be 2.484.

I do not believe the "trim to" length is extremely important, it is just important to trim it below the maximum length.

My cases averaged over the 2.494 ,maximum, so it is time to trim them.

So, how do we go about this task?

There are many different ways to do the job, but I will show you how I do it.