Fired from a Ruger LCP with a 2.75 inch barrel into two 16in blocks of Clear Ballistics 10% gel.

First up the Remington offering. Average velocity of 840fps. The chrony did not register the velocity of the bullet fired into the bare gel but the bullet penetrated 9.5 inches and expanded to about .62 inches. The round fired thorough the heavy clothing had a velocity of 832fps and penetrated 19.75 inches with no expansion.



The Underwood 102gr +P had an average velocity of 972fps. The velocity of the round fired into the bare gel had an impact velocity of 954fps with 10 inches of penetration and about .66 inches of expansion.  No velocity reading on the round into the heavy clothing but the penetration was 11.5 inches and expansion was also about .66 inches.      




http://www.sgammo.com/product/380-auto-ammo/500-round-case-380-auto-remington-golden-saber-102-grain-jhp-ammo-gs380b

https://www.underwoodammo.com/380-acp-p-102-grain-brass-jacketed-hollow-point/

https://www.clearballistics.com/

Dang that Underwood stuff looks good for a 380. It might be a better choice for those determined to carry a mouse gun..

What bullet is Underwood using for this load?

Golden saber apparently

That's what I figure given the weight but wanted to see if the OP might know.  Underwood just lists it as a JHP on their website.

Fixed it for you.

The .380 is the only cartridge that isn't a good performer with the heavier bullets. I've done the Ultimate Defense which uses the same bullet and had gotten similar results with it doing my own tests. The Underwood looks like a bad performer as well based on your data.

I'll stick with the Hydra-Shoks.

They both look like gold dots to me

Those are not Gold Dots.

They are Golden saber bullets.

There are better choices than the 102 gr golden saber.  They tend to under penetrate when they do expand and they over penetrate when they fail to expand.

There are a half dozen or so loads that use the Hornady 90 gr XTP, and it performs well in both short and longer barrel .380 ACP pistols.

In a 2.5" barrel you can get around 800 fps and at that velocity it will produce 13" penetration in bare gel with perfect expansion.  In a 4 layer heavy denim test however expansion falls to about 60% with penetration around 14" to 15" when it does expand about around 18" when it does not.

If you increase the velocity to 1000-1050 fps in a 3.5" to 4" PPK/S or PP type .380 ACP, it will give near 100% reliability in heavy denim and penetrate 14"-15".

That makes the 90 gr XTP an excellent performer in a PP or PPK/S size pistol and a very good performer in a 2.75" pistol like the Kimber Micro or Sig 238.

Federal's Premium 90 gr Hydro Shok load is also a good choice.   At 900 fps it will give  12-13" penetration in bare gel with perfect expansion.  In heavy denim however expansion is only reliable about 20% of the time with only partial expansion the rest of the time.  Still, penetration for the partially expanded bullets is 14" to 15" and it's still only around 18' when it fails to expand.