I was a junior in high school when I started handloading metallic. Mo mentor, no internet and a Speer#11 was my only source of information beyond whatever Guns & Ammo might say in any issue at the time. I loaded .38 Special and I didn't own a scale. I had a full set of Lee dippers and the Lee "slide rule" decoder thing to tell me what charge weight of which powder I was getting. This method of powder handling came because I was on an absolute shoe-string budget. It was 3 or 4 years later when I purchased my first scale, and even then it was the very low-cost (but accurate!) Lee scale.
My next scale was an ultra-low quality Frankford Arsenal digital and it sucked out loud. Rather than dink around with the check weight that came with it, I kept a 55 grain .224" SP bullet (a particular one, not grabbed randomly from a box) and once that junk scale warmed up, I would check it often with that one particular rifle bullet. When it read "55.1gr" then I knew the scale was working at that moment.
I truly have no idea if that bullet weighed 55.1 grains, but when my craptastic scale said that it did, I went forward in the process. And I loaded probably ten thousand rounds of ammo across numerous calibers doing that and I had enormous success doing so.
It didn't matter what the bullet weighed, it only mattered that it always weighed the same. All the loads I built and fine-tuned and referred back to later to re-create all ran wonderfully. They may not have been exactly the weight that I recorded on each box of ammo or in my reloading log, but every time I set up to make that load, the charge weight was the same as the one that had worked.