I chronographed some factory ammo I had today. This was all purchased in the last year or so. Hopefully this is useful for somebody. These are average velocities from 3-5 rounds.
Firearm: Ruger GP100 4.2"
Ammo
Buffalo Bore Heavy 357 180gr JHP
1285 fps, recoil was such that 20 rounds was plenty to shoot for me
Advertised velocity: 1500 fps
Federal Hydra-Shok 158gr JHP
1153 fps, this was comfortable for me
Advertised velocity: 1240 fps
Underwood 125gr JHP
1444 fps, also comfortable
Advertised velocity: 1700 fps
Sig 125gr FMJ
1259 fps, this was a light load and pleasant
Advertised velocity: 1450 fps
I could see the BB and Underwood making the advertised velocity out of a rifle, easily. The Sig and Federal look like they're based on a longer barreled pistol than your GP100.
Good info! Thanks for posting it.
Thanks. I wasn't very surprised the numbers on the boxes were optimistic out of a 4.2" barrel.
That's often the case, but not always. https://www.luckygunner.com/357-mag-125-grain-hp-barnes-tac-xpd-20-rounds#geltest Barnes claims these @1200fps out of a 2" barrel. This test clocked them at 1251 and 1418fps out of a GP100 like yours.
Thanks, when things return to normal, and it's available, I'll check that one out.