What are JSP rounds used for?

S

Sturmpanzer

Moderator
I was going to the range and stopped at Walmart..all they had in .357 was a box of JSP rounds..now I know this os a good hunting round and I use them in my AK, but what are they used for in revolvers?... Hunting?... Are they good EDC rounds....might be a dumb question...
 
I've shot quite a few deer with the .357mag in revolvers and a few in lever guns chambered for that cartridge. The vast majority of them were shot with Hornady XTP JHP bullets and almost always the bullet did not pass through the deer. I tried using some JSP bullets and some of them did pass through. I think from my experience that the JSP don't expand as rapidly as the JHP bullets and will penetrate a bit deeper. As far as being more lethal, it's a wash. I've never lost a deer shot with the .357 in either a rifle or handgun, and that's with over fifty taken in that caliber. I'd think for something heavier than a deer, a JSP might be better. I also think that for something heavier than a deer a larger caliber would be better also.
 
It's hard to generalize as there are many variables .For handgun hunting I like an exit hole as the is more bleeding for better tracking. I've had a deer run 75 yards before dropping any blood on the ground .The long belly fur absorbed lots of blood ! The bullet [44 mag] stopped against the hide after going 30 " !! Bullet opened to .50 cal. The only of that bullet I recovered ,one shot all I needed !
 
I think of that 158gn jacket soft point as a do anything load for my 357. The American Eagle version shoots really well in my 3” GP100.
Incidentally, I was at my Walmart yesterday, and they had the Rem-UMC 125gn semi-jacketed hollow point in the 100rd box for $53. Had to get a box for old times sake.
 
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Here's a 125gr .357 Magnum before and after it went through my doe.
 
JSP proves the point that hard cast "woods defense" bullets are pointless (ie, hard cast Buffalo Bore or Underwood 10mm etc).

Though lead is soft, without that hollow cavity shape, they don't deform. Even at 357 revolver levels.

JSP gets almost the same results as FMJ, if any difference at all.
 
JSP proves the point that hard cast "woods defense" bullets are pointless (ie, hard cast Buffalo Bore or Underwood 10mm etc).
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Yeah right! Tell that to the guide in Alaska that saved his clients and himself from a Grizzly with Buffalo Bore's 9mm Keith hardcast Outdoorman loads!LOL. Right, it was a fluke you say.
OK, but it wasn't pointless to him!
 
wild cat mccane, I fired some 325 grain hardcast lead WFN loads into a green oak log and also fired some 300 grain JSP into the same log. This was from a ruger .45 colt, so I realize we're not comparing apples to apples, but the WFN penetrated several inches while the JSP only made it a little over an inch. In another test, a hardcast 350 grain .45 colt WFN went through 12 layers of 7/16 OSB and kept going. I'm not knocking a JSP, but I am convinced of the penetration capabilities of hardcast lead bullets.
 
Isn't the lead in "hard cast" a more rigid alloy than what gets used inside a JSP? The partial jacket probably exerts an influence on expansion and works to limit leading in the barrel. The degree to which those things matter will vary by caliber. They are fairly popular for hunting in .357 magnum and should be fine for self-defense. A hollow point might work better but with shot placement being equal, I probably wouldn't lose sleep over the difference.
 
Isn't the lead in "hard cast" a more rigid alloy than what gets used inside a JSP?
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It is. And, that's the point.

What is a JSP used for? The same things all bullets are used for. They expand a bit less than hollowpoints, and penetrate a bit more, generally.

And sometimes, that's what you want.

Hard cast bullets are made to withstand firing at speeds a soft lead bullet isn't suitable for, and so generally don't expand much if any, and penetrate deeply.

And, sometimes, that's what you want.
 
woods defense

The woods defense bullets (hard cast slugs) are NOT intended to expand. By design, they are penetrators, gaining some wound channel (maybe) by their flat meplat, but first and foremost, penetrating through hair, fur, hide, dense tissue and bone to the vitals of critters big enough to cause harm. Handguns in general are underpowered for use against that type of threat, and one of their short comings is lack of pentration due to low velocity and the wide assortment of handgun bullets that ARE intended to expand. The hardcast family attempts to address that.

I'm not entirely certain, but I'll add that if all is equal, hardcast lead slugs will have a tad higher velocity than a copper jacketed slug of equal weight.

It was stated earlier that "though lead is soft, without that hollow cavity, they won't deform". That is debatable. I'd offer that a .357 JSP will indeed "deform" but it may or may not "expand", and a JHP is subject to the same speculation, though expansion might be more expectable. There are lots of examples of soft lead roundballs from muzzleloading rifles taken from game animals that deform and expand, forming flat near disk like shapes. I've taken .32 roundballs from small game that certainly had deformed, and flattened into wide disk shapes larger than their initial diameter. BUT, that is at muzzleloading RIFLE velocities. Ballistic gel shots from BP handguns show deformation of both roundball and conical, but often not much.

As noted by 44AMP, JSP's are intended to expand less than a JHP. Accordingly, penetration should be a bit higher. But the softer lead core of a JSP is a bit of a liability on large boned critters, and will probably not equal the penetration of a hard cast lead bullet of equal weight and velocity.
 
Bullet construction has more to do with expansion than bullet shape. There are HPs that do not readily expand just as there are SPs that will expand and separate readily. Similar to the differences between swagged lead bullets and hardcast, jacket thickness and core construction have much more to do with expansion/non-expansion than a hole in the tip. While JHPs generally expand more and at lower velocities than JSPs, it ain't always the case. Many plated HPs act like FMJs.
 
Learned alot... I use JSP's in my AK for just the reasons stated above...virtually the same penetration as FMJ, but better expansion... Great for a combat rifle, but didnt know about handgun use... Kinda leery about using it as a CC round due to over-penetration... Will stay with mt 125 gr Golden Sabers for carry.... Good info on the hunting use, as thats what I thought they were for...never went handgun hunting....
 
Sounds reasonable to call it a "Jack of all Trades" round"... Same reason I use the type in 7.62x39...same barrier penetration as FMJ, but that extra expansion iin soft tissue..but as a hunter, wouldnt over expansion ruin alot of good meat? We can tell that Im not a hunter...
 
Take note on Buffalo Bore's website, the hard cast is called the "outdoorsman." Cute...
But hide the children...their FMJ +P+ 124gr is called "PENETRATOR"

Now let's go to Underwood's website.
Underwood loads the copper (harder than lead) Leigh Xtreme bullets (Defender and Penetrator). I do think these should get more attention, regardless if the round actually twists or not.

Underwood's wood ammo is a FMJ 147gr +P+. https://underwoodammo.com/product/ha...-metal-jacket/

"FMJ-FN bullets are non-expanding, powerfully penetrative bullets that are designed with your woods defense needs in mind; whether fending off wild hogs or black bears,"

Now is the point someone is going to point out both are flat nose. Yep. However, flat nose isn't "crushing" more in the small calibers. http://www.gsgroup.co.za/articlepvdw.html

Please visit the 10mm thread where no one can respond back where I say 10mm is pretty much useless because FMJ 40 does anything an FMJ 10mm does and 10mm hp bullets are all (except XTP) old technology (ie Speer Bonded vs Speer Gold Dot--new in 2018 at 40 fps levels) that benefit from higher speeds where 40 HST and Gold Dots don't require it to get better results--https://thefiringline.com/forums/showthread.php?t=595488&page=2

Now onto JSP...it might be better than FMJ, but it also may not at all.
 
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For what it's worth,
I did chrono the Buffalobore 9mm +P Outdoorsman out of my shield and was a little dissapointed. 147 grain @ 998,1000,1015 for average ME ft. lbs of 326

But my LCRX 3” with BB 158 grain HC outdoorsman got 1076,1087 fps=415 ME
The .357 version however out of the 2" LCR was in the 600 # range, and out of the 4" security six was up to 700 plus foot pounds.
 
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