B.S. A round nose bullet has more mass farther back and they tend to be longer overall. This requires deeper seating so they will fit in your magazine. A 200 grain 10mm bullet is not intended for 40S&W due to space constraints, just read a speer reloading manual. If you wanted to load round nose, you may want to drop to 155 grains in 40S&W. Now the 357 sig is notorious for losing case neck tension with the wrong choice of bullets. If you disagree with me you don't know what you are talking about. Round nose bullets have to be seated so deep, the part that would normally be held tight in say a 9mm case is below the neck in the 357 sig and the tapered portion of the bullet is all the case has to hold onto. There has been a few articles written on the subject by people more knowledgeable than myself.
And as far are armor piercing handgun projectiles, don't be so foolish as to believe ammo companies don't take body armor penetration into consideration when designing ammo to sale the public. A 38 super shooting 90 grain round nose at above 1500 fps would be hard for a vest to stop. Just because it would not be a traditional load doesn't mean people would not buy it.
rc
And as far are armor piercing handgun projectiles, don't be so foolish as to believe ammo companies don't take body armor penetration into consideration when designing ammo to sale the public. A 38 super shooting 90 grain round nose at above 1500 fps would be hard for a vest to stop. Just because it would not be a traditional load doesn't mean people would not buy it.
rc