ShootisPRS,
Yes, you have to check fit in your own chamber. The value of the formulas is to see whether you are getting a match to a load's development conditions or not. If you can't achieve that match, but have to seat deeper, then you can expect you may have to use a lower charge weight. Only working the load up for your chamber will tell you.
I have loaded .380 with 110 grain .357's in the distant past. Small Interarms mini-19l1 type pistol. No issues, but its operating at around .45 Auto pressure levels, of course. The gun had chamber room, obviously. Also, the powder space being so small, I actually dispensed charges with a scoop made from a BB Cap case and trickled the charges up to weight for it. Didn't load a lot of them.
My concern to check chambering arises from .45 Auto, where I've encountered Eastern European cases (forgot which one—this was about 10 years ago) which was loaded with .450" jacketed bullets in a cases so thick that no cast bullets could be loaded in them without getting a jam on the way into chamber. I'm just expecting there may be some 9 mm out there that is extra thick.
I also remember we had a post within about the last year or so on Remington bullets that the box said were 0.355" but that mic'd at .356". The member called Remington who admitted that dimension changed (they were outsourcing these bullets), but they weren't going to change the packaging every time a lot came in a little different. Anyway, the bottom line is they shoot fine.
BTW, if one has concern about extra friction from a fat bullet, either moly or hBN coating can be applied and will lower the pressure needed to swage the bullet into the throat.
Yes, you have to check fit in your own chamber. The value of the formulas is to see whether you are getting a match to a load's development conditions or not. If you can't achieve that match, but have to seat deeper, then you can expect you may have to use a lower charge weight. Only working the load up for your chamber will tell you.
I have loaded .380 with 110 grain .357's in the distant past. Small Interarms mini-19l1 type pistol. No issues, but its operating at around .45 Auto pressure levels, of course. The gun had chamber room, obviously. Also, the powder space being so small, I actually dispensed charges with a scoop made from a BB Cap case and trickled the charges up to weight for it. Didn't load a lot of them.
My concern to check chambering arises from .45 Auto, where I've encountered Eastern European cases (forgot which one—this was about 10 years ago) which was loaded with .450" jacketed bullets in a cases so thick that no cast bullets could be loaded in them without getting a jam on the way into chamber. I'm just expecting there may be some 9 mm out there that is extra thick.
I also remember we had a post within about the last year or so on Remington bullets that the box said were 0.355" but that mic'd at .356". The member called Remington who admitted that dimension changed (they were outsourcing these bullets), but they weren't going to change the packaging every time a lot came in a little different. Anyway, the bottom line is they shoot fine.
BTW, if one has concern about extra friction from a fat bullet, either moly or hBN coating can be applied and will lower the pressure needed to swage the bullet into the throat.