Originally Posted by
runfiverun
james's oil analogy is about right. I agree. There's a LOT of R&D and money tied up in additives that make oil thick when hot and thin when cool. When I was in automotive school this came up, and the prof gave a really good lecture on the chemistry behind what makes that happen, and why heat eventually breaks the stuff down in an engine and the viscosity/temp range changes. I've also seen charts showing different brands and advertised weights vs. actual independent lab tests, I can assure you that 5W-30 isn't 30 weight at 200 degrees, maybe 18 weight.
we don't make multi visc lubes,i have tried to find a lube that maintained the same hardness in cold and hot. Me too, that's a tough nut to crack.
they kinda felt about the same sitting in the cold and the warm but they weren't.
the lube just didn't have the flex or the ability to go liquid and make that seal when cold.
the lube in the bbl was stiff too. Just when you think you have it figured out, you go shooting and professor Gun says SORRY, please try again!
357 max had the cold bbl first shot flyer when hunting and he worked out his micro wax specifically for that.
i don't think it would hold up over a 20 shot string at 80*'s though. It will not, but it does what he designed it for beautifully. He lives near Canada, I live near Mexico, not much weather overlap between our two locations.
it seems when we try to fix one problem you lose at the other end. Always a trade-off.
a temp stable carrier/lube combo is the issue.
i sent ian a p.m. last night about this.
when target shooting i just burn one no big deal, but that isn't an option for hunting.
white lith is, so far, one of the better temp stable ingredients i have found, and so is atf in our temp range. Synthetic two-stroke oil seems to be another one with those characteristics.
the carrier is the issue right now for me,maybe a silicone would work [i dunno haven't researched it]
i do know silicones were tried by harris in the 50's but he wasn't satisfied [or didn't try them fully] as he suddenly shifted to his 50-50 mix and lauded it's praises like they were a sponsor of his race team. I wanted to dink with silicones, but the thing is they're weird. Felix and I discussed this at length a few years ago, and he was initially worried about "sandy barrel syndrome" where under enough temperature and pressure the oils might revert to silica. The other thing is that silicone "grease" is a silicone base oil that's fluid but thickened with fumed silica. Not sure fumed silica would hurt a gunbarrel (they use it to thicken milkshakes), but that's not the tack I was looking to take for a thickener/base. Plus, silicone is a lousy metal-to-metal lubricant. I decided not to try it.
i have fought with this for quite a while now and the best answer i still have is to soften my lube for the winter and hope it doesn't fail when it gets warm.