Headspace is the distance measured from the part of the chamber that stops the forward motion of the cartridge to the face of the bolt. Used as a verb headspace refers to the interference created between this part of the chamber and the feature of the cartridge that achieves the correct positioning. Different cartridges have their datum lines in different positions relative to the cartridge. However, we’re going to be using that tool to give us a reference number that we are going to use to properly set our sizing dies. If you want to maximize the accuracy and brass life of your brass and ensure that you’re sizing your brass correctly.
In this article, you will get an overview of the headspace gauge kit which is a must-have tool that every reloader should have. So let’s explore it now…..
The reason why this tool is so important is to make sure that we’re sizing our brass appropriately. If we don’t size the brass enough it’ll likely be obvious to us because we won’t be able to Berger Load Data properly fit it in our chamber. However, more likely the case, if we follow the directions we’re going to go over in a minute here we could be pushing that shoulder back too far during our reloading process and possibly cause a safety issue. We can use it in making sure our measurements are referenced correctly is what we need to do.
If you are familiar with reloading what we’re looking for is anywhere between a one-in-three thousandth bump. Three thousand is plenty for a semi-automatic rifle; some people try to go for as little as possible and some people shoot for one. If we’d set our size and die to push our shoulders back to where our factory was. We would certainly be working this brass a significant amount pushing this back fifteen thousand that is very bad practice for a 300 Winchester Magnum case.
When we talk about a tool being a headspace gauge, we’re typically always referring to this as shoulder bump measurement. We’re never going to change the headspace on this particular case because the headspace on the 300 Chester magnum is actually off the belt. The headspace measurement is actually from where this case would hit the bolt face to the shoulder of this belted Magnum. That is not going to grow and shrink with our sizing die, it’s how far we push the shoulder backs. It’s going to cause weakness and a possible split case or case at separation neither of which we want. Extending the brass life as well by moving the shoulder back as little as possible. However, the least work we do on this brass the longer it’s going to last and the more consistent reloads.
Shooting for one to two thousand bumps on our shoulders is really what we’re looking for, going as much as 3,000 as possible but three-thousandths is more of a dimension for a semi-automatic rifle.
Moreover, reloading is a great hobby for those that are careful and want to be able to get the most out of their rifle but safety is always the most important factor.
- A dies you could be pushing the shoulder on a 300 Winchester Magnum back far further than you need to. You won’t have to look very far to find a case at separation in 300 Winchester Magnum.
- Setting our dies correctly and using this tool to do it is the only way and should know how to do it. Make sure that our die setting is appropriate and repeatable.
However, you can slide your dies in and out, locked rings locked down unless you reload for a different rifle in the same caliber. One of the other considerations is susceptibilities that it goes over is the possibility of a light primer strike. But, you have to make sure which one would be more apt in your application but something you might want to look into. Either way, this is a fairly inexpensive tool and every loader reloads the bench.