What if I used grease instead as oil can dry up? Or would the carbon trapped in the grease increase it's jamming?
I've been using Fiocchi 230gr FMJ.
If you're planning to leave your guns in the safe 300 days out of the year, I recommend Frog Lube.
It lasts about a year, probably longer but it starts to turn golden brown.
It's more work initially. You have to remove any previous oils and thoroughly clean it. Then coat it with Frog Lube all over inside and out. I use the paste and brush it on with a small brush.
I then heat it in the oven as directed. That step absorbs the protectant into the pores of the the metal.
After it cools completely, I gently wipe them down. A complete layer of Frog Lube remains and protects better than most lubes I've seen tested.
When you take it to the range, you don't even need to oil it. As the gun warms up from shooting, the Frog Lube softens/melts and lubes it automatically.
After shooting, clean as usually, reapply the Frog Lube only enough to replace what you cleaned off, then warm it in the oven.
Basically, if you're looking at semmi-long-term storage, this is a very good product. For extremely long term storage, most MILSURP sellers seem to find the guns preserved in cosmoline. it's a combination of grease and oil and it's very difficult sometimes to get the firearm totally clean with only one try.
I just checked, and Amazon lists cosmoline as a spray-on rust preventative. I may have to check YT to see how that stuff stacks up against Frog Lube.
Amazon also shows a product called Fluid Film. One of the auto channels in NY I watch uses this to protect cars and truck from rusting out from all the salt used during the Winter there. This is not a lubricant, so you'll still need to address that when preparing to shoot.