Neck tension is a big deal when designing/producing hand loads. Competitive shooters, myself included, need to have this correct to be successful marksmen.

Everyone who makes their ammo has to be on top of this regardless of use. Yes, people can half-ass this step; I guess shooting somewhat decent makes them happy. If someone says to you, “Oh, stick a bullet in the case and shoot it. It doesn’t matter,” that person’s mom probably smoked jazz cigarettes while pregnant.

What is neck tension?

When you insert/seat a bullet into a brass cartridge, the amount of pressure holding your bullet is called neck tension.

Hold a pen in your fist. Now, imagine the pen is a bullet; when you squeeze it, more or less, you are simulating neck tension. A person using specific tools can adjust how much neck tension there is holding the projectile. (Easier said than done.) that can and does have a dramatic effect on accuracy.

Before I get a lot of emails, I will give you a place to start on this journey. Whatever bullet you are using, purchase that company’s reloading manual. They test the hell out of their products. They have tools to measure things most people could only dream of or even remotely be able to afford.

I’ve never seen one, but they even have a device capable of measuring chamber pressure. The information they provide is reliable. If it weren’t, they would get sued daily. Never get your load data from someone online. That is asking to thin out your gene pool.

When you first start dialing in your neck tension/pressure, it would be best if you were cautious. If you’re not 100% certain of what you’re doing, for the love of God, don’t do it.

If you have too much tension, you can dramatically ramp up the pressure on your firearm’s action. If you go too far, it is boom time. Messing this up is one of the top five reasons for people’s guns blowing up. Keep in mind that “we are making tiny bombs and setting them off next to our face.”

An often-overlooked issue in setting the correct tension is properly determining the brass’s thickness in the area where the bullet is seated. I was guilty of this mistake for more time than I care to admit.

Do not get stingy! Purchase top-of-the-line tools to measure the brass thickness correctly. Failure to do this will completely throw your numbers off. Your measurements will not be what you think they are. As I have said in the past, cheap tools equal unreliable results. If you don’t know where you are starting, how do you know where to go?

A quick side note:

proper reloading equipment is almost indestructible; if you take care of them, they will outlast your children’s children. I know people get tired of the saying, “Buy it once; cry once,” but you hear it so often because it couldn’t be more spot-on in the case of reloading gear.

I cringed several times while buying equipment, but the products were so good I would do it again without a second thought.

When I initially wrote this article, it was entirely too long. I decided it would be best to write a stand-alone piece in my how-to series on different ways to measure and adjust neck tension if you want to read it (click here).

I want to say the subject isn’t too complicated, but that wouldn’t be correct. With this write-up, I’m just trying to give you enough information to get your head in the game.

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