I'm looking at ordering some .380 95gr coated bullets from bayou.
They show that they are .355 in diameter. The same weight for 9mm is .356 diameter I would like to load both with the same bullet.
Will that be an issue? Which one should I go with, .355 or .356?
Thank you,
David.

The nominal bullet diameter for both rounds is .355 inch. I think a few people fudge a thousandth or so if it's a lead or plated (or coated) bullet.

Probably a moot point. Have you found any 9mm load recipes anywhere for a 95 gr bullet?

I have not done well with my 9mm pistols with bullets at 95grs or lighter.
Trying to force it to do double duty might be a mistake.

The lightest in a 9mm for me was a 115gr bullet for any accuracy with +/- OAL adjustment possible.

All weapons are different, it may work for you.

Typically lead should be .001 larger than the bore diameter and .380 and 9mm have .355 bore diameter so you go with .356. However it's common for people to label lead bullets for 9mm at .355 and have the bullets be .3555 or .356 or even a little larger.

Typically 9MM bullets start at 115 grains but you probably can get a lighter bullet to function however I stick with 115 or larger in 9MM.

There is load data on Hodgdon's web site. Several different powders. Wow... a "standard" pressure round over 1200fps. Never thought of doing that before.

When I was first trying out coated bullets I loaded 100 or so rounds with some coated Bayou 95 grain RN bullets I had originally bought for loading 380 Auto for my old Husky m/1907 auto pistol, just to see if I could induce leading and had loaded them very close to the max loads shown by Hodgdon on their loading data site. I couldn't induce leading but didn't really try them at a long distance to see how accurate they were. I do remember that POI was off as compared to loads using 115 or 124 grain bullets though.

I do recall loading up a bunch of Winchester 95gn FMJ for my 9mm S&W SD9VE using published data. Did it after selling my LCP and wanted to get rid of what was left of .380 bullets. I was actually very surprised at how accurate and consistent the rounds were landing on target 10 yards out. They measured .355", again, they were FMJ bullets.

FWIW, I've always been told that lead and coated bullets should be just a hair bigger.

In that the .380 is a 9mm kurtz,(short), the short answer is yes.

Since the 90s',I've been using Reminton 88gr JHP,Speer 88gr JHP,and Sierra 90gr JHC for loading 9mm. With a Beretta 92 my standard max load chronographs at 1500fps. Functions fine,tried them in other 9s' too. I've loaded them higher/faster but settled on the 1500/beretta 92 load. I have yet to chronograph them in smaller 9s'.

How about a 124gr. 9mm bullet in a 380acp load?

That would be a bit too heavy for a 380, IMO. But I have loaded 115 RN in 380 in the past and it did good.

There are some sources for 9mm loading data with a 95 grain bullet, but you'll also need:

1. a pistol that will feed reliably with the short bullet and its short OAL;

2. a load that will cycle the slide reliably; and

3. a bullet that won't lead at the 1200-1300 fps velocities you'll probably need to cycle the action.

It's a tall order.

Jacketed bullets will handle the velocity just fine. Plated bullets will also do ok, but they are at max velocity at this level. Cast bullets will need to be coated and made from a suitably hard allow that matches the pressure of the load. Unfortunately, that isn't the same hardness that is well matched to a .380 ACP load with a 95 grain bullet.

You can also find load data for a 115 gr bullet in a .380 ACP. but these loads tend to be hard on blow back operated pistols and will batter the frame.

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A better approach to do double duty with a single bullet is a 100 gr plated bullet as it is much more .380 ACP friendly and you can get them in a hollow base design that is a bit longer and can be seated longer in a 9mm for better feeding. Plus the extra weight of the bullet helps cycle a 9mm pistol at the 1200 or fps velocity limit of the 100 gr plated bullet.

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My preferred approach is just to order 500 or 1000 124 gr plated RN bullets for my 9mm pistols and 500 or 1000 100 gr plated bullets for my .380 pistols at the same time.

If you're eventually going to shoot them all anyway, there's no real advantage in trying to make one bullet work for both calibers.

In fact, I would only consider trying to make one work for the other if I were in the middle of a component shortage where I could not find a more suitable bullet for one or the other.

I bought both my son's LCPs for Christmas last year. Nosler 115 JHPs shoot the best for both of them.

It's not the weight or diameter that's a problem, it's the ogive. 9mm and 380 ACP bullets, even if the same weight are different. Can you use them, yes, should you? I probably wouldn't.

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I have a very old Lyman manual that lists some 380 loads using a 125 gr LRN bullet at over 1000 fps !!!!!! I wouldn't want to shoot those in any of today's pocket-pistols!

Those old timers really liked pushing the limits, didn't they?

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