Grok:
Buffalo Bore’s 9mm +P Outdoorsman load (147gr hardcast flat-nose bullet at ~1,100 fps) is marketed for 4 to 6 feet of straight-line penetration through flesh and bone. 
This is the manufacturer’s design goal for deep penetration in large game like bears (black or grizzly), emphasizing the flat-nose hardcast bullet’s ability to crush through tissue/bone while staying nose-forward and avoiding deflection (unlike round-nose designs). 
Real-World Bear Incident
In a documented 2016 case, Alaskan guide/outfitter Phil Shoemaker used this exact load from a compact S&W 9mm (Model 3953/3954) to stop a charging grizzly at close range (6–10 feet). He fired 7 shots, hitting vitals/shoulder areas multiple times. The bear was stopped and later skinned. 
• They recovered 4 bullets.
• One photo showed an entry on one side of the back with the bullet tip visible just under the hide on the opposite side (indicating near full-body penetration on that path).
• Other shots reached lungs/shoulder areas without exiting, consistent with substantial but angle-dependent penetration through thick hide, muscle, bone, and gristle. 
This matches the ammo’s reputation for bear defense when shot placement is good. Independent tests (ballistic gel, wetpack, barriers like wood/frozen meat) often show 24–43+ inches of penetration, supporting the 4–6 foot claim in ideal straight-line paths through softer tissue. 
Context and Caveats
• Not guaranteed full exit: Actual penetration varies with shot angle, bone hits, bear size, and fat/muscle layers. Hardcast excels at straight, deep tracks but isn’t magical.
• It’s purpose-built for woods/backcountry carry (over-penetration is a feature for bears, a potential issue for humans/urban use).
• Many sources (including Buffalo Bore, user reports, and articles) highlight it as one of the better 9mm options for bear defense due to penetration over expansion. 
For the most authoritative details, check Buffalo Bore’s product page for the load and Shoemaker’s account. Always prioritize shot placement and consider larger calibers if possible for dedicated bear country.
Ammo matters.