superdude

Tests show that the recoil force is different with different bullet weights when using the same gunpowder. Heavier bullets produce slightly less recoil. https://www.shootingtimes.com/editorial/power-factor-recoil-bullet-weight-gives-edge/99399

That's not quite accurate. The only traditional semi-rimmed 38 Super case in that table is the Remington. Other brands make semi-rimmed cases, but are not listed there. All the others in the table are specifically noted as rimless super comp and clones. It's from the article I posted the link to, which describes the known rimless Super Comp and TJ cases made at the time. Other semi-rimmed brands are not in the table because the article focuses on the rimless variants. Most of those same brands also make semi-rimmed 38 cases. Right? Starline has two semi-rimmed 38 Super cases in addition to their Super Comp and TJ lines.

Some readers might find the article below of interest. https://www.ssusa.org/content/rimless-38-super-brass-everything-you-need-to-know/

Why?

Maybe some useful information here: https://www.shootingtimes.com/editorial/fast-9mm-loads/388612

I broke a firing pin on a S&W 686 with a hammer mounted firing pin while dry firing. It does happen.

Published load data with pressure testing will tell you if your load exceeds standard pressure - or not. Consult loading manuals for that information.

Maybe something useful here: https://www.ssusa.org/content/handloading-the-38-short-colt-for-competition/

Maybe some useful information here: https://americanhandgunner.com/gear/handloading-lead-free-frangible-bullets-for-pistols/

Maybe something useful here: https://www.ssusa.org/content/handloading-the-38-short-colt-for-competition/

Which ones?

The lube is most likely the source of the smoke. If you like wadcutters (or any lead bullets) but don't like the smoke, switch to Hi-Tek coated bullets.

You'll have to slug it to know. Never assume. Always measure. 9mm, 38 Super, and 38/357 all have the same SAAMI barrel specs. .355 groove diameter +.004. Anything within that range is in spec. https://saami.org/wp-content/uploads/2023/02/SAAMI-Z299.3-2022-Centerfire-Pistol-Revolver-Approved-12-13-2022.pdf

In case anyone is interested, the article below discusses this topic and provides evidence showing that a heavier bullet has less recoil than lighter ones when loaded to the same power factor with the same powder. https://www.shootingtimes.com/editorial/power-factor-recoil-bullet-weight-gives-edge/99399

Online calculators are here: http://kwk.us/recoil.html https://www.jbmballistics.com/cgi-bin/jbmrecoil-5.1.cgi

I've found A#7 to work fine in 9mm minor ammo. I don't have much experience with it and 115 grain bullets, but it produces very nice groups with 124/5 grain bullets from a 5.0 inch Kart barrel. For example, 6.0 grains and a 125 HAP at 1082 fps from the 5.0 inch barrel. 10 shots in 1.53 inches at 25 yards. And the velocity extreme spread was low at 27 fps. It's definitely worth trying.

Did it get bulged, or maybe the wide region was made during the rifling process? If the barrel is bulged, I would expect there should be a bulge on the outside dimension of the barrel as well, which might be detectable with calipers? Maybe?

The Eley rounds I had some years ago measured 1.253" OAL +/- .001". The SAAMI max OAL for 38 Super is 1.280". You'll have to measure yours to see if they fit within those specs. That said, some mags can be a little short front-to-back. The way to test them is to use ammo with a known, measured OAL and see what fits and travels up/down through the mag without rubbing.

Some of the common ones are in this article: https://www.ssusa.org/articles/2018/1/9/how-to-use-9-major-in-a-short-barrel/

Those bullets have been around forever. They are in my old Lyman loading manual, circa 1970s. Matts Bullets sells them. https://www.mattsbullets.com/index.php?main_page=product_info&cPath=65&products_id=225

It's not unusual to see barrels of the same length produce different speeds, and for shorter barrels to be faster than longer barrels. https://www.ssusa.org/articles/2021/8/16/pistol-barrel-length-and-velocity

N105 or Accurate #7 will work, at, or just a little above, published load data, depending on your barrel. https://www.shootingtimes.com/editorial/super-powders-for-the-38-super/99160 Recoil force will be just a little more than a 45 Auto with a 230 grain bullet at 850 fps, so maybe like a 45 +P. 125 @ 1500 fps and 10 gr of powder = 5.60 ft pounds in a 2.5 lb gun. 230 @ 850 fps and 7 gr of powder = 5.30 ft pounds in a 2.5 lb gun.

The 9mm and 38/357 have the exact same bore and groove diameter SAAMI specs, which are 0.346" bore and 0.355" groove +.004". Anything with a groove diameter between 0.355" and 0.359" is within spec for either caliber. Therefore, there is no such thing as a 9mm bore/groove diameter and a separate and different 38/357 bore/groove diameter. They are the same, like it or not. The only difference between 9mm barrels and 38/357 barrels is their rate of twist. 9mm = 1:10". 38/357 = 1/18.75". But twist rate is optional. I've slugged many 9mm and 38/357 barrels and their groove diameters cover the same range, except some Colt revolver barrels that were under 0.355". Colt has a reputation for that, at least the old barrels. I don't know about the new ones. The SAAMI bullet specs are different. 9mm - 0.3555-.003 38/357 = jacketed 0.358-.003. Lead 0.359-.003 SAAMI specs: https://saami.org/wp-content/uploads/2019/02/ANSI-SAAMI-Z299.3-CFP-and-R-Approved-2015-12-14-Posting-Copy.pdf The SAAMI bullet specs are different. 9mm - 0.3555-.003 38/357 = jacketed 0.358-.003. Lead 0.359-.003 Which is why we see 9mm jacketed bullets at 0.355" and revolver jacketed bullets at 0.357".

Most lead 9mm bullets are .356. Many plated 9mm bullets are, too.

you might find this article of interest: https://www.shootingtimes.com/editorial/reloading-heavy-bullets-in-9mm-luger/99514 if you're loading them for a revolver, you can have a very long OAL. like 1.200, 1.250, whatever you desire. Do the ones that fail the case gauge still fit in the gun? The gun is the 'gauge' that matters.