Case sizing

[CouesNStuff]

New to hand loading so I'm genuinely curious on some of the more experienced folks thoughts here. If I have once or twice fired brass, and I take the empty cases and drop them into the action of my rifle and the bolt closes and opens smoothly, is there any need to resize the case? Or what about trimming the case? If I take my calipers and measure the cases, the fired cases are showing different measurements, +-.001 inch. But like I said, they fit in the action and don't hang up at all. So, how often are you guys resizing and trimming your cases?

 

[Ballcap]

You will have to resize the neck to seat a bullet. I would check case length and trim if needed. If they are smooth in the action you should be fine with just a neck size. I would guess you are not loading near max and if that works for you, great, you will get more life from your brass.

 

[Dmoua]

It’s normal for brass to not be fully fire formed with one or two firings. You can full length resize the brass without bumping the shoulder.

As far as trimming brass. Trim five to ten thousands below minimum and it’ll take you a few firings before you need to trim them again. Always trim them to the shortest piece of brass you have. Variance of +- 0.001” is normal.

 

[JFK]

You will need to neck size at minimum. Some people just neck size after firing but at some point you will need to bump the shoulder back a couple thousandths. Other people just full length size every firing. Pros and cons to each way of doing it. A standard full length die with sizing button is probably easiest to setup correctly for a new loader and still makes very good ammo.

Trimming needs to be done when the brass grows and gets close to or exceeds sammi max. This won’t always be something you can verify by chambering a cartridge. Measure your cases after every firing to determine if trimming is needed. When I trim, I trim them back to sammi min length so you get more firings between having to trim again. Not trimming your brass and letting them exceed acceptable length can cause dangerous pressure spikes.

Focus on doing the basics well and build a process so it’s the same every time.