9mm .3565 125gr rn bullet in a .38/.357 k frame?

[Whit30]

Hello,
I could use some advice please.
I've been trying to find a suitable bullet that I can cast that will work in my 9mm Sig P226 and my S&W 38/.357 mag k frame.
I have some .3565 125 gr rn hard cast that work well in the Sig. The info says .3565. With my cheap dig. Calipers, I average mostly .3545-.3550.
Will these work in the K frame? Do I need to slug the barell of the S&W to be sure?
They are lubed but when I cast my own I will probably go with High Tech coating or last resort powder coat. Prefer to use the High Tech.
I need to dig out my Hornady book this weekend but I hope to use Bullseye as I use it for the Sig 9mm.
Any help and advice would be very appreciated! Thank you!

 

[DeplorabusUnum]

For best results in your K frame, I'd get some pin gauges and size the cylinder throats. Matching your bullet size to the throat size will give you the best accuracy. .3545 - .355 will likely be too small for great accuracy from the revolver. They will shoot fine, but may scatter a bit.

If you powder coat the bullets it will add about 3-4 thousandths to the width. You could then run them through a sizer die once you figure out what size your throats are. I size mine at or .0005 over cylinder throat size.

I'm not sure what high tech coating does to the width. I've never tried that coating.

Slugging your barrel probably isn't necessary for the revolver. Sizing to the throat size is enough. It might be a good idea for your Sig, just so you know bore diameter and groove diameter and can size your bullets to fit your barrel and make sure you're engaging the rifling.

 

[Ivan the Butcher]

The most affordable molds are by Lee. They make most bullets in 1, 2, & 6 cavity so you can choose you investment and production rate.

The very first mold I bought was a 124 gr round nose 9mm 2 cavity mold, I lubed and size on a used Lyman lubra sizer (often called a G & H press) I bought a .355 sizer for 9mm and a .357 for 38. I cast around 250,000 of those bullets and sized most of them to 9mm (I shot over 40,000 of them in my Full Auto, and over 5000 in a S&W Model 39-2) And I sold thousands at gun shows (I found my last box of 500 when cleaning up last week!) I also size for 38 and shot them in my various J, K, L, & N frames. They work well, I never tried them is 38 Super but they would be fine, as they were great in 9 Largo (9x21).

Lee makes bullet sizer kits for use on a regular loading press, but bullets have to be lubed separately. I have been experimenting with sizing bullets before coating, and find If I soak the bullets in 50% rubbing alcohol and run them through the Lee sizer wet, they don't have to be lubed!

I have gone away from lighter cast bullets in 38 and gone to 158 SWC. I have sized those to 9mm and used them for sub-sonic silencer ammo in the full auto also.

Lee used to make and still may a 146gr. SWC/HP single cavity mold, This is a great mold for both 9mm & 38, It just takes a while to cast a pile of them!

If you are going to be "Coating" your castings, different alloys cool to different "As Cast" diameters and many alloys will cool to smaller diameters if cast from higher than average temperatures. There is a nice section about these subjects in Lyman's Cast Bullet Handbook (I have 3rd edition) and the same section was in Lyman Load Manual #46.

You will need a good quality Micrometer to tell what you are doing. (People say a dial caliper will do, but buy the time you buy one good enough, a good Micrometer is less expensive!) You need a lead pot thermometer also.

There is a good deal of simple arithmetic in making good quality bullets. Casting bullets has existed at least 100 years before (successful) brain surgery! Don't let a little math scare you off from doing it right!

Ivan

 

[reddog81]

The Lee 358-125 rf is an common mold that can be used in 9mm and .38. I’m not sure you’ll be able to find any right now but it’s a good one to look out for. You have to seat the bullet kind of deep in the 9mm case but there’s tons of info online about loading for it.

If you’re casting and coating. Your own bullets you’ll need sizing dies and can usually use .356 or .357 for 9mm. You can get by using the .357 for .38 special also but generally .358 will get you better accuracy.

 

[Scharfschuetzer]

For a one for all 9mm and 38/357 bullet, I use a 146 grain cast Lyman 9mm bullet sized to .358" in my semi-autos and my S&W revolvers. For S&W revolvers, your .355/.356 diameter may be too small in diameter for good accuracy and may promote some leading due to gas blow by due to incomplete obturation.

Believe it or not, the .358" diameter is very accurate in my Browning High-Power as well as a Beretta 92 and it shoots as well as anything else in my S&W revolvers too. As there is no crimping groove for revolvers, I just use a light roll crimp over the beginning of the ogive and that holds the bullet in place, even at 1,000 fps in 357 Magnums. I taper crimp for the semi-autos.

2" 10 shot groups from both types of handguns at 25 yards are routine with the .358" diameter. Your guns may vary, but having used this bullet in at least six different hand guns of 9mm and 38/357 calibers, I'm sure that it'll work for you too.

As far as powders go, I've used Bullseye in the 38 Specials, but I use Winchester 231 in the 9mm and the 357 loads with this bullet.

 

[rockquarry]

The Lee 358-125 rf is an common mold that can be used in 9mm and .38. I’m not sure you’ll be able to find any right now but it’s a good one to look out for. You have to seat the bullet kind of deep in the 9mm case but there’s tons of info online about loading for it.

If you’re casting and coating. Your own bullets you’ll need sizing dies and can usually use .356 or .357 for 9mm. You can get by using the .357 for .38 special also but generally .358 will get you better accuracy.

If I had some slightly undersized bullets, I'd try them anyway. May not work well but there are exceptions to everything.

As for .38 Special bullets...for years I ran all my bullets through a .358" SAECO bullet size die. Bullets came out slightly less than .358", however, but worked fine. During the last year, I began doing serious experimentation with bullets run through a SAECO .357" die. These bullet come out at a little under .357" if cast from wheelweight or other moderately soft alloy. With a harder alloy, they will be .357".

Anyway, I did a lot of benchrested 25 yard group shooting comparing the bullets sized in a .357" die vs. those sized in the .358" die. Generally the smaller bullets were more accurate, enough to see the difference without measuring.

I've accumulated too many .38 and .357 Colt and Smith & Wesson revolvers over the years, and a few of them do shoot more accurately with the larger bullet. I'm not going to size to different diameters as it's inconvenient, so everything gets the smaller bullets.

I'm not suggesting anyone use bullet diameters other than what they use now if they're satisfied with the results.

 

[mikld]

Fortunately the 4 molds I use for my 38 Specials, 357 Magnum and 9mm all drop bullets .358"+. Lee, NOE and Lachmiller

Using a .355" bullet in your revolver might produce barrel leading and in some cases lead "spray" on the cylinder face, top strap and forcing come, but the bullet may obturate enough at the throat to work OK. For shooting cast bullets successfully and cleanly, you must know your gun. In the case of a revolver, measure the cylinder throats, slug the barrel and measure the diameter of the bullet. For my revolvers/cast bullet shooting I size my bullets to the same diameter as the cylinder throats (works in my 6 revolvers)...

 

[rockquarry]

Fortunately the 4 molds I use for my 38 Specials, 357 Magnum and 9mm all drop bullets .358"+. Lee, NOE and Lachmiller

Using a .355" bullet in your revolver might produce barrel leading and in some cases lead "spray" on the cylinder face, top strap and forcing come, but the bullet may obturate enough at the throat to work OK. For shooting cast bullets successfully and cleanly, you must know your gun. In the case of a revolver, measure the cylinder throats, slug the barrel and measure the diameter of the bullet. For my revolvers/cast bullet shooting I size my bullets to the same diameter as the cylinder throats (works in my 6 revolvers)...

I agree for the most part. A bullet that will pass through the throats with slight resistance usually works well. Sometimes, a smaller bullet will obturate enough to provide good accuracy, but everything, including alloy composition, pressure, and velocity have to all be just right for that to happen.

I think some may try to use a caliper to get an exact figure on bullet diameter and that won't work well. You must have a micrometer. Of course, if your bullets shoot well, you don't need any measuring device.

 

[Nevada Ed]

I am not as picky as some shooters.

I will take a new bullet and load maybe three different powders
with a starting "Target load" and go out and see if it will stay inside
a 10" paper plate at 10 yards, shooting offhand with one and a two hand hold.

If you are lucky, one might turn out to be a keeper.
If the pattern is "Large" , then you will need to go to shool on that bullet and find out what the problem is, if you have more than 500 bullets.
I usually burn up 200 rounds in just testing in the early sessions but that is different with every loaded and their needs.

Have fun.

 

[STORMINORMAN]

Bought a bunch of Rainier .356 plated 130gr RN that were probably designed for 38 Super. Found out they work OK in 38 Special and 9mm, not at all in 357 SIG.

I realize this is "apples vs, oranges" as far as the O/P is concerned, but before the "what is acceptable accuracy for the intended use" question is answered, the "will it work for both calibers" needs to be determined. Feeding (OAL, really) for 9mm is more tricky than for a revolver.

Bullseye certainly can work for 125gr in both 9mm & 38 Special: might not be the same amount, though...? Probably not.

Certainly interested in your successes!

Cheers!