If you're a serious hunter and a handloader, a record-keeping system is as important as a handloading press. Without written records, all you have to rely on is your memory, which is okay if it's photographic. But I don't know of anyone with that kind of retentive ability, and I certainly don't have it. So, I write things down—and you should, too.
Over the years, I've tried all kinds of record-keeping systems, but they were all failures … until I finally sat down and figured out a system that addresses my needs and is easy to maintain.
Here's what works for me.
Whenever a new gun (rifle, pistol or shotgun) comes into the house, I immediately make up a file folder for it. I label it by caliber, make and model. I then throw in a few blank handloading data pages that I've made up to suit my purposes, which I can print off at home. If I received an instruction manual with the gun, I'll put that and the warranty info into the folder as well. This becomes the home for all the information I want to retain about the firearm.
Naturally, handloading recipes are recorded on my homemade data pages, as are the results observed, including group size and pressure observations. But I'll usually go further and snip the groups from my targets, taping them onto the back of the relevant data sheet. Doing so gives me a quick visual reference as to whether the group is strung vertically, horizontally or is nicely round. If I try factory ammo in that gun, those results are recorded in the same way.
But beyond handloading recipes, I'll also record the distance from bolt face to barrel lands, so I can monitor barrel wear.
Lately, I've also started measuring and recording the twist in every barrel I own. That obsession started when a friend arrived with a new rifle that a gun shop sold to him as having a specific twist rate. I was suspicious, so we measured it and it wasn't even close. The maximum overall length of a cartridge that will work through the magazine is also recorded. All of this data is listed on the inside front cover of the folder, where it can be easily referenced.
Each folder is then housed in a file drawer that is split in two—guns I still own and those I don't. That latter section being invaluable when another gun of the same caliber arrives and I want to look back to see what worked and what didn't.
It's a system that works for me, and if you don't have one, feel free to copy it. There are various free data sheets available via an Internet search. Or, if you want professionally prepared ones, check out the selection available from Sinclair's. They have the most comprehensive selection of data logs I know of.
Whatever system you use, be assured that keeping good records will result in more accurate shooting and therefore more varmints and predators on the ground.