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why do some people choose JHP over FMJ?


tenchu74
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I just got 1000 124grn fmj's from Delta Precision and am about to start reloading for 9mm. (Already do for 40 & 45).

I've noticed that some people use 124grn jhp's from DP instead of fmj's. Why? When your just punching paper & steel shooting matches why would you use a jhp? What am I missing? Thanks.

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In some guns JHP's are more accurate.

Also, there are some Open gun shooters here, and in those guns exposed lead in the bottom of a typical FMJ bullet is not desirable - cloggs the compensator.

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As with the other replies, I've always heard JHPs are generally more accurate primarily due to the idea that the JHPs have more surface area to contact the rifling in the barrel. (ie. they are a bit longer bullet given the same weight FMJ)

Edited by razorfish
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exposed lead base some dont like, Nowadays we have TMJ though, Also factor that many of the bulk bullet hollow points like montanna gold are not designed to expand like a defensive hollowpoint, It was kinda surprising to me, as when I started shooting IDPA and more sport shooting the ranges and school I attended has NO Hollowpoint rules as a safety measure. Figured it was more universal, got to hawaii and seems all the local open guys were running golden sabrs, something I did not like LOts and lots of shrapnel from them Many will argue it was the steel not the Golden Sabres, but I dont buy it. I currently also dont allow hollowpoints at my range . Its over an hour to the nearest hospital.

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In most of my pistols, jhps are a lot more accurate than fmjs. Also, as said, jhps don't have exposed lead at the base. I only run jhps through my open guns.

As far as safety goes, a lot has to do with the quality of the steel targets being shot at. If the target is cratered, and bent it will turn bullets all over whereas a good, smooth target shouldn't.

Over the last 20 ears of shooting, I've been hit with several fragments, but, the one that put me to the ground was a fmj that hit me in the middle of my forehead, due to a ricochet.

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Many shooters feel that JHP is more accurate than Ball/FMJ. I think that accuracy is anecdotal from pistol to pistol. See which your handgun prefers.

Every gun I have shot has been more accurate with JHP bullets so I think its beyond anecdotal. Same goes for rifle rounds there is a reason match bullets are not FMJ but rather boat tail hollow points.

Pat

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Im sure theres a number of reasons people choose JHP over FMJ, but as for the accuracy issue, the... (Warning: I just realized I wrote all of this... Long answer:) The more mass you can have at the perimeter of a spinning object keeps the center of that object more stable and on a truer path. Same thing that makes a gyroscope stable; the mass of a spinning object forcing itself out from the center keeps the center stable as long as it spins appropriately. Also the more mass at the base of the object if its moving in a direction rather than spinning in place keeps the front end centered.. think rifle match ammo... there should be some good threads on that on other forums. A hollow point pistol round actually accomplishes both of these dynamics. Moves mass to the perimeter and base. That's why even though a hollow point may not be designed to expand, it should "balance" out of the barrel quicker, stabilizing quicker and staying on a truer path in relation to the direction your barrel was pointed the moment the bullet left the barrel. Takes less time to find its "center" basically, meaning its center is usually closer to the intended flight path... Vs a bullet that "wobbles" momentarily from more mass closer to the middle that may not perfectly centered and might be pointed slightly off the intended line at the moment of stabilizing.

Slightly less long version: The barrel spins the bullet close to perfectly, but if the mass of the bullet is off center, "point" of the bullet not centered perfectly, it will have to find that center upon exiting the barrel. So the closer the mass to the perimeter, the quicker the stabilization, the less likely it is to be pointed off line at the moment of stabilization, the more consistent from shot to shot. The hollow point accomplishes this better. Also since the cavity contains no mass as its empty space, the center doesn't rely on where a "physical" tip of the bullet may be; rather it will spin more perfectly as it determines its own center, or axis, and is less influenced by imperfections in the bullet itself. It happens very quickly but it does happen.

As I am new to posting in forums, I will work on in the future shortening the posts... Hope I didn't bore anyone...

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I am interested in hearing the science that determines a JHP bullet more dangerous at a range than FMJ or other ball ammo that bounces all over the place? Sounds like range operators that should know better are buying into Hollywood BS. I would bet that they are also using the term, "cop killer" too...

Edited by ErichF
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The only thing I can think of is that yes, they are buying into "hype", unfortunately... I would assume a JHP on a range behaves the same way it does "on the street", and likewise for the FMJ... The bullets don't know where they are! I guess if they have a range accident they figure there's a better likelihood of it being easier to "save" if its a pass through??? Of course if it continues to "pass through" would that be a lesser of two evils? I don't know really, it's early, just grabbing my coffee, maybe I'm not thinking out of the box enough. Never been to a range like that.

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RE post #15...while most of the long answer is applicable to high velocity rifle rounds as variables affecting accuracy, the actual math and reasoning does not bear out for pistol caliber velocities. The longer bearing surface for a given weight is the primary variable why JHPs are more accurate than FMJs at pistol caliber velocities.

RE post #17, there is NO science that determines a JHP is more dangerous for shooters and observers, in fact, quite the opposite. Ricochets and or deflections with FMJs (generally) have more retained energy than those of JHPs.

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