Forum member Andy (aka GreyMist) has completed an interesting test, with five (5) different types of .243 Winchester Brass. He collected Federal, Lapua, Remington, and two different lots of Winchester-brand brass. Then he selected ten (10) cases at random from each brand and measured their weights.
6mm Creedmoor vs .243 - Cartridge Comparison - Sniper Country
Winchester .243 Winchester Super Short Magnum Unprimed Rifle Brass
6.5 Creedmoor [Ultimate Guide]: Military's New Caliber - Pew Pew Tactical
What does caliber mean for a gun? What does gauge mean? What is the difference between a clip and a mag? - Quora
243 Winchester Brass Weight and Capacity Tested « Daily Bulletin
243 Win « Daily Bulletin
243 Winchester « Daily Bulletin
243 Winchester Loading Data - The Old Deer Hunters
Lapua .260 Rem Brass Proves Very Uniform « Daily Bulletin
Cartridge Guide « Daily Bulletin
February « 2022 « Daily Bulletin
Copper Unit of Pressure (CUP) Defined by Hodgdon « Daily Bulletin
243 Winchester - Wikipedia
Starline 243 Winchester Large Primer Pocket Brass (Bag of 100