.357 bullets in a 9mm?

[ShootistPRS]

CAUTION: The following post discusses loading possibilities beyond or not covered by currently published data for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.


Has anyone here used a 140 grain JHP .357 diameter bullet in their 9mm? I've heard that using the larger diameter bullet helps with accuracy in some pistols and has little to no effect on pressure. The pressure part seems counter-intuitive to me but I have seen other test results with more difference in diameters that show little if any rise in pressure.

I have a lot of the 357 bullets that I will never use in my 357 so, I'm thinking "out of the box".

[Hanshi]

I've never liked the idea of heavy-for-caliber bullets in the 9mm or .38sup. While I've cast and had success with a 140 grain lead bullet in the Super, both are only loaded with jacketed bullets of 125 grains or lighter. While I don't think you'd run into any problems doing as you asked about, I'd go slowly and carefully; you might just find a great load.

[cdoc42]

This post falls in line with one I planned to start today. Hoping I'm not stealing the thread, let me continue.

I generally shoot a 115gr "FMJ" HP -one that has no visible lead at the hollow point, and I pondered trying the 125gr JHP that I use in my .38/.357. My plan was to ask advice because of the difference in size of the bullet diameters.

The 115gr measures .355" while the 125gr is .356-.357 (best I can do with my digital caliper). Is the larger diameter a problem?

As well, the 115gr measures 0.530" OAL while the 125gr is 0.549" with the lead tip measuring 0.142" and the jacketed area measuring 0.407."

I'm assuming seating depth should not be as deep with the 125gr compared to the 115gr - correct?

Thanks!

[buck460XVR]

I would be concerned about 140 grainers in 9mm because of the projectile length. In order to properly feed you may have to seat them deep. Seating them deep mean less case capacity. Less case capacity may mean low velocities. Iffin it were me I'd find a way to shoot them outta my .357s and get an appropriate bullet for the 9. Sending poorly shooting bullets downrange IMHO, is just a waste of good powder and primers.

[egd]

I see no problem with the weight. After all 147 gr is a standard weight range for the 9mm. I'd just use some variation of 147 data. As usual, start low and work up.
As for the diameter, it really depends on your gun. Some guns like a fatter bullet, some don't. I think it's worth a try.

[NoSecondBest]

I loaded some in my 9x21 when I was shooting competition and some of them shot very well, some didn't. I never detected a pressure problem but I wasn't hot roding them either. Start low and work your way up.

Referring to my old notes on this subject: the bullets I used were Gold Dots which are not actually jacketed bullets. They are basically a cast bullet with a thicker plating.

[Nick_C_S]

What buck460XVR said.

They're gonna set deep. All bets are off with any kind of load data. You'd be completely on your own; and ya better be mindful that the smaller the space, the faster the propellant behaves. In this case, their behavior may be radically different that what you'd expect - much faster. Take heed. I'd advise against the whole concept, actually. I find it rather concerning.

egd, take note too. There's more to using load data than just comparing bullet weights. Seating depth is at least as big of a factor. This discussion is an excellent example thereof.

I would not use 147gn load data to load 140gn .357 Mag revolver bullets. The 147 bullet has a much much longer nose, and doesn't sit nearly as deep in the case.

Another issue is that 357 Mag hollow point bullets were not designed with feeding in mind. Their shape is based purely on terminal ballistic performance (an advantage SD revolver ammunition has over semi-autos - when used in a revolver, of course ), with reliable feeding never coming into the design picture.

And yes ShootistPRS, a larger diameter bullet is likely going to result in more pressure - all else being equal (which rarely is).

Side note: 9mm barrels tend to be loose for whatever reason. I don't load a lot of 9mm in general. But when I do load lead, I use 147gn slugs, sized to .357" - and they're very accurate. More so than their .356" brethren.

[Wheeljack]

I load 147gr bullets in my 9mm. Things to note are, what is your bore dimension, have you slugged it? What kind of bullet are you loading....lead, plated, jacketed. General information says size lead .001 to .002 over bore size. Plated .001 over bore size and jacketed at bore size. For heavy bullets the slower powders are suggested. Seating is a big problem, due to lack of data. A lot of data uses the XTP bullet and then gives the OAL. The length of the XTP bullet is not shown, anywhere. I was told it was .650" and I would like confirmation is anyone out there can help? The 147gr RN bullets I use are .667" long. So if I seat my 147gr bullet to the COL data listed PLUS .017, the pressure should be the same. I actually load bullets as long as possible for best fit. The bullet should seat in the chamber and can be turned easily and not bind. Then the bullet should not to too long not to fit in the magazines. This most often results in the space in the bullet is more than the XTP gives at listed COL and therefore the pressure is less than the printed data. If the COL for a XTP bullet is 1.100 and I load to 1.150 then my load has less pressure and it may even need more powder to come up to the maximum pressure listed in the data. On top of this is the accuracy of measurements. I set my bullets for 1.150" but they range from 1.150 to 1.160. The length of your bullet does not change the pressure of your bullet but how deep you seat it does. Does this sound right??

[5whiskey]

Nick makes an important point. You can usually use generic "JHP" data so long as you purchase a projectile designed for the caliber. When you're trying to force-fit something you better pay close attention to what you're doing.

It could work, and the slight ^potential^ bore size difference (likely not significantly different) doesn't matter so much. Using a bullet that seats too deep in a straight walled pistol cartridge can get real dangerous real fast. Again, you may stumble across a great load for your pistol and I think it can be done. Just know what you are doing and start low in the chosen data, working up carefully.

[kmw1954]

I find this interesting in that the Lyman Pistol and Revolver Reloading Handbook has a listing for a lead 130gr 9mm bullet with 10 different loadings for it along with a 147gr lead bullet with 8 different loadings. Then it also has a listing for a 130gr FMJ of unknown manf. with 9 different loadings. Then another for a 147TMJ with 8 loadings.

Also if you go to Xtreme website they have a 135gr HP and a 135gr RNFP

So I find it hard to understand why it would be so difficult to come up with a load that would work and work safely.

[5whiskey]

So I find it hard to understand why it would be so difficult to come up with a load that would work and work safely.

All of those are likely designed for 9mm. Despite the similar bore diameter, 38/357 revolver projectiles are designed for their application. That application is different than projectiles designed for a semi-auto. 2 different 140 grain projectiles, with the exact same diameter, can seat much differently because of different bullet construction. You likely can make a load work, and work safely, if you understand how important seating depth is in a straight walled pistol cartridge and pay close attention to it. Literally 1/100th of inch in seating depth can make the difference between in-spec loads and hotter than +p loads in some cases.

I don't feel quite as ominous about it as Nick does, but I would urge the OP to proceed with caution and pay close attention to seating depth if he decided to try it.

[kmw1954]

You likely can make a load work, and work safely, if you understand how important seating depth is in a straight walled pistol cartridge and pay close attention to it. Literally 1/100th of inch in seating depth can make the difference between in-spec loads and hotter than +p loads in some cases.

1st if I have to worry about 1/100" then I'd better give up and stop now. Even with my old cheap setup I can hold 0.007" with cheap plated bullets. 0.10" would be huge and quite noticeable I would think. This is also why I do not use certain fast powders, because they are pressure sensitive or in my view, unforgiving.

Yes I will agree on seating depth and camber volume. A while back I started loading Berry's Hollow Base and found no published data for starting load or case length. The 124gr Hollow base is not the same size and shape as the 124gr RN and as I later found out they do not load the same. Powder charges are completely different as are listed seating depths.

[ShootistPRS]

Well, I have been reloading for 45 plus years and I always start low and work a load up to find accuracy. I never go beyond published data. I was recently reminded to check the overall length in the 9mm by inserting the loaded round into the chamber so I have that for a background. I see I made a mistake in my original post and I would like to correct it. I use 140 grain bullets in my 357 but I have a few boxes of 125 grain bullets that I will never use in the 357. I will attempt to load the 125 grain bullets in 9mm. I already know that I can load at below the starting loads with my 9mm so starting at the minimum listed load is easily done. As far as pressure is concerned, my gun is rated for +P ammo and I load using the older standard loads, so pressures should not be a concern. My gun does have a very short chamber so overall length may be a challenge and the part I am most concerned about is feeding. I only use the 9mm at the range so this development process is in no way critical for me.
I want to thank you all for the caution recommended and being a cautious reloader has kept all my fingers attached so far. If you are interested in my results I will post them.

[g.willikers]

Another vote for using 147 grain bullets, sized .357 for 9mm.
My favorite is the truncated cone flat nose lead version.

[Longhorn1986]

My wife shoots 147's in her nines and much prefers the heavier bullet over the 115's. She gets much better accuracy as well.

[Wheeljack]

What is interesting about seating depth is the lack of data. The Lee manual shows lead lead bullets with different OAL's. What is the shape of the bullet? My guess, and it's a guess, is that the data is for a round nosed bullet like the drawing at the start of the data. Is the data for the 38 special only for a flat nosed bullet? I can't see the data being applicable to both a round nose and a wad cutter. It's a jungle out there. Would sky diving be as much fun if were perfectly safe? Don't forget your chronograph.

[Jim Watson]

I find the chronograph very useful.
Instead of a recipe hunt for an exact combination of components, I start definitely low and work up until I get to where I want to be. I select for minimum functional, best accuracy, minor power factor, major power factor or factory equivalent. The only time I have exceeded anybody's published load was for heavy .38 specials to be shot in magnum guns.

I have shot .358" semiwadcutters in 9mm with no "pressure signs". Using load data from when that was considered a reasonable thing to do.

[Unclenick]

Seating Depth = Bullet Length + Case Length - COL

From that formula you can figure the seating depth of published loads if you have the bullet length. Often you don't, and this is one reason published loads are often applicable only to the bullet used, and not automatically to other bullets the same weight. The JBM site has a length database that includes some pistol bullets, but it is far from complete. Once you have the bullet length, though, and find the seating depth for a known good bullet, you can then rearrange that same formula to learn what COL you would need for another, different length bullet to give it the same seating depth:

COL = Bullet Length + Case Length - Seating Depth


So now the complications:

The new COL might not chamber because a stubbier bullet seated out will present its ogive closer to the lands.

Using the same seating depth does not make for same jump to the lands, so it's not a given that the pressures will match.

A bullet that makes a longer jump to the lands may reduce pressure despite matching seating depth. This is not a factor QuickLOAD has an argument for.

A bullet designed for a magnum revolver may have a thicker, harder jacket than one for 9 mm. That could raise pressure a bit. Check the manufacturers range of usage velocities for a quick compare. Faster normally means a thicker or harder bullet, but asking the maker is best.

Using a bullet 0.002" bigger in combination with brass that is on the thick side will jam in some chambers. You want to be doubly careful that there is still a little clearance for the case to let go of the bullet. 0.0005" will do, but you may need to use a slug or a chamber cast to be sure how much is available to you.

Then, in the end, you are back to load work-ups as the final step in determining the safety of the load.

In the 70's or 80's I spent $50 on a surplus French police MAB. .32 ACP. The jacketed commercial bullets are 0.311. The bore was 0.309". Firing oversize is not particularly unusual. Almost all the SAAMI specs have the maximum bullet diameter 0.001" over nominal groove, and the grooves can be smaller than nominal by another 0.001", though there is a minimum groove cross-sectional area, and that is affected by different land configurations as well as bore and groove diameters.

As to it being more accurate, in cast lead bullets it is often so. This has to do with the fact they are easily swaged to an off shape in a throat and no gas leaks can be allowed if accuracy is to hold up. I've not noticed oversize being more accurate with jacketed bullets, particularly. Among rifles, most Palma match barrels are on the tight side, but the purpose there is maximizing velocity to stay supersonic as far as possible. British rifle competitors used to swear by the accuracy of their .309" groove barrels. So, for jacketed bullets, I just don't see the advantage, especially not in a pistol, a device for which a 4 moa group is considered darn good and fully competitive on 50 yard targets.

The 25 yard 5-shot group below was shot with 0.451" bullets in a barrel that was 0.451" across one diagonal and 0.4515" across the other. Not even round. Jacketed bullets seem to handle of bit of oddness remarkably well.

[ShootistPRS]

Unclenick,
That is a very detailed write up on how to calculate OAL and seating depth. Due partly to the differences in chamber freebore in pistols of different makes I find it easier and more accurate to use the "plunk" method of dropping the loaded round into the chamber. My CZ 75B has the shortest chamber+freebore of any 9mm I have ever seen. I have run into problems twice with the specified OAL being too long and having to seat the bullets deeper. Now it is just mart of the loading process to be sure the finished round chambers properly.
I do wonder if you have ever used a .357 diameter bullet in a 9mm before and if so what were your impressions?

[5whiskey]

My CZ 75B has the shortest chamber+freebore of any 9mm I have ever seen. I have run into problems twice with the specified OAL being too long and having to seat the bullets deeper. Now it is just mart of the loading process to be sure the finished round chambers properly.

Shootist this mirrors my experience with CZ firearms. I have to seat many cast offerings shorter than the recommended minimum OAL for them to chamber in my CZ. I load fairly mild loads because of this.

[Unclenick]

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.