Difference between JHP and XTP?

So then is a Berger match grade VLD rifle bullet-
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If the jacket is completely closed at the tip (no visible opening) then it wouldn't be a "hollow point", but if there is a hole (an opening of any size) where the jacket form the tip, it is a hollow point.

A bullet can be a hollow point, designed for maximum accuracy and not intended to be an expanding bullet (many match bullets are) or it can be a hollow point where the hollow point is intended to be an aid to bullet expansion, such as most handgun bullet hollowpoints.

The issue of match bullets was brought up to the US govt when US sharpshooters began using them against "insurgents". Some people claimed the US was violating the "Geneva Convention" (which we were not, it is actaully Hague Accords that refer to the use of hollow point ammo).

Best I can recall, the US response was that while the "open point" match ammunition were technically hollow points, we were not violating the intent of the accord because they were not expanding bullets, nor were we violating the letter of the accord because the accord is only applicable to the uniformed forces of signatory nations, which, the insurgents were not.

I think it's valid to at least be aware of those differences and what the implications on use are.
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Of course. Knowing how the bullet is made and what its intended uses are is always important.

Functional differences in performance don't determine if a bullet is a hollow point, or not. What determines that is if there is a hole (a hollow) in the bullet point or not. I have some 44 ammo loaded with a hollow point, the jacket completely covers the nose except for a small area right in the center where there is an exposed lead spot with a small hole in it. They don't expand at 1200fps but they are "hollow points"

To more directly answer the OP's question, the Hornady 7th edition (2007 but the first book I grabbed with the .38 180 XTP in it has one load table for the XTP and the SIL 180gr bullet. SO, I'd say that data for any .38 cal 180gr bullet with the same amount of bearing surface would be a useful guideline.

Using proper reloading practices reducing starting loads and working up to the published load levels (if possible) in your gun, of course.
 
In relation to the terminology, in my experience hollow point generally refer to bullets that are intended to expand. Whereas open tip, generally refers to match style bullets not intended to expand.
 
Shadow9mm said:
In relation to the terminology, in my experience hollow point generally refer to bullets that are intended to expand. Whereas open tip, generally refers to match style bullets not intended to expand.
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"Hollow Point" has nothing to do with "intent" to expand. In relation to accepted terms in the ballistics field, an OTM (Open Tip Match) bullet has a portion of the jacket that is "open" at the point and also on the interior. In that the lead core stops short of the jacket. The tip is open on both sides of open tip of the jacket. Some OT bullets are in fact, intended to expand. OT bullets, for match shooting, are falling out of favor to polymer tipped bullets. Some have a cavity under the tip, some do not. The benefit of the open tip, ballistically, was that the pressure in the cavity helped to form a "better" ballistic profile in that it changed over the velocity range. But tipped bullets are, over the parameters we shoot them, more consistent and less likely to be damaged. Tubbs,

A JHP (which includes many styles) is where the jacket, but supported by the lead core to the interior, stops before the center point of the bullet and the lead core, in some fashion, is exposed through this opening in the jacket. It has no physical point, but rather where the point would be is "hollow". In order to be a JHP, it is made as a cup (jacket) and core bullet. The cup of the jacket is around the lead core and the base is enclosed. FMJ bullets have the core put on the other way leaving the base of the lead core open. TMJs have a disc of jacket material to close the base opening.

Gold Dots are plated bullets, so they do not have a cup, but are still generally referred to as JHPs by the masses. Speer uses the term "hollow point cavity". The copper plated round nose slug has the point punched in with a die (creating the gold dot) and then formed with another die into the final shape.
 
MarkCO said:
"Hollow Point" has nothing to do with "intent" to expand. In relation to accepted terms in the ballistics field, an OTM (Open Tip Match) bullet has a portion of the jacket that is "open" at the point and also on the interior. In that the lead core stops short of the jacket. The tip is open on both sides of open tip of the jacket. Some OT bullets are in fact, intended to expand. OT bullets, for match shooting, are falling out of favor to polymer tipped bullets. Some have a cavity under the tip, some do not. The benefit of the open tip, ballistically, was that the pressure in the cavity helped to form a "better" ballistic profile in that it changed over the velocity range. But tipped bullets are, over the parameters we shoot them, more consistent and less likely to be damaged. Tubbs,

A JHP (which includes many styles) is where the jacket, but supported by the lead core to the interior, stops before the center point of the bullet and the lead core, in some fashion, is exposed through this opening in the jacket. It has no physical point, but rather where the point would be is "hollow". In order to be a JHP, it is made as a cup (jacket) and core bullet. The cup of the jacket is around the lead core and the base is enclosed. FMJ bullets have the core put on the other way leaving the base of the lead core open. TMJs have a disc of jacket material to close the base opening.

Gold Dots are plated bullets, so they do not have a cup, but are still generally referred to as JHPs by the masses. Speer uses the term "hollow point cavity". The copper plated round nose slug has the point punched in with a die (creating the gold dot) and then formed with another die into the final shape.
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My understanding was that in open tip match bullets, the cavity also help shift center of mass further back by removing load from the front to make the bullet more stable.
 
So, just how many angels can dance on the head of a pin?
This is the type of hair splitting that drives newbies away. Hole in front of the bullet? Hollow point.
 
So, just how many angels can dance on the head of a pin?
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I agree. We/me were talking about JHP's, XTP's, and expansion in water jugs. I like running rabbit trails in the weeds as much as my dog. IMO You guys refined this into nothingness. Back to the topic at hand, I previously attached photos of my Berrys Hybrid Hollow-point Expansion test, where the 0.356" bullet expanded to 0.777" here:
https://thefiringline.com/forums/showthread.php?t=615677
 
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AI

"Microsoft's "A.I." research option:
"Hornady XTP bullets and JHP (Jacketed Hollow Point) bullets are both types of handgun ammunition. The main difference between the two is that XTP bullets are designed to expand upon impact, while JHP bullets are designed to penetrate a target1."
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That is the problem with AI. It is sometimes, false, out of context or non-sense.
JHP bullets are designed to expand on impact. They are NOT a penetration phenom. They are designed to limit (over) penetration.
The other big problem with AI is that if the "user" is an idiot, they can easily reach wrong conclusions, and potentially rely upon them with adverse consequences.
 
AI just looks at what is said on the web without really understanding it. I wouldn't be surprised if it found information on the last three decades of development of 9mm HPs that penetrate better than the Silvertip JHPs at the famous FBI Shootout in Florida did and misinterpreted that to mean expansion wasn't one of the JHP objectives. That is if it got that far. It could also just be quoting some uninformed web "authority." Keep in mind how much ignorant stuff is posted in the mountains of "information" generated by gun control groups every year, and then remember the AI looks there for answers to your questions, too.
 
This is even more of an issue with the .454 Casull. Note that Hornady makes an XTP and an XTP-Mag. The reason is the jacket is thicker in the "Mag" for use in higher velocity handguns. Freedom Arms will suggest the use of their bullets for that reason without explaining it.
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Ben Amonette, ballistician formerly of ATK explained it to me clearly when I asked for help with .460 S&W Magnum at the bench. The XTP-Mag bullet is a more robust design that will prevent a lesser-constructed bullet from going out-of-round in the high pressure violent transition from cylinder to forcing cone at potentially 65,000 PSI. The forces on the base of the bullet attempt to turn it in to an ellipse and the XTP-Mag bullet is designed with protection of the forcing cone in mind.
 
I always love the conversations on wording , terms and acronyms . Where's Guffey when you need him ? I'm sure he could have cleared this up in just 5 pages of post , 6 infractions and 20 post being deleted

COL and COAL "should" be two different acronyms . Just like headspace and case headspace are two different things - oh snap!

As to JHP and XTP , interestingly enough even Hornady had/has two different meanings for there XTP . To be fair the old XTP clearly has a different design then the new style so That explains why they called the old XTP a flat point (FP)

Old 38cal - 158gr FP-XTP

ulwwUM.jpg

ajdeWc.jpg


Compared to the newer 38cal 180gr XTP

1qN39C.jpg

XuH78e.jpg


Hornady is known to change there titles of things . Like the comparator that used to be called

IqHP8x.jpg


Which they now call a headspace comparator removing the word cartridge .

So both the above bullets have holes in the tips and neither is formally called a HP by Hornady lol
 
MG,

C.O.A.L. And C.O.L. are different. You can tell because one has three letters and the other has four. The confusion stems from the fact their definitions are the same. ;)

If anyone has old Riflemen or load books written before the Korean war, you find the four-letter version to be universal. Today the load manuals overwhelmingly use the three-letter version. It's OK, as long as you don't confuse their shared definition with that of headspace. :D

I think the real difference between the JHP and the XTP is the former is a physical description of bullet construction and the latter is an exercise in commercial branding.

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MG,

C.O.A.L. And C.O.L. are different. You can tell because one has three letters and the other has four. The confusion stems from the fact their definitions are the same.
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Oooh double snap !! Haha

Ha ….ha….haha…. He said headspace ha :-)
 
I have always labeled my handloads, "OAL-OG" which I interpret to me at a later date or to those looking over my shoulder, as, "OverAll Length to the Ogive.

I recognize AMP44 would argue about the use of Ogive in this instance, but I have since read about a description of seating depth of one of the shooting journals that doesn't disagree with what we apparently all understand it to imply.
 
I recognize AMP44 would argue about the use of Ogive in this instance,...
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44AMP just enjoys a good argument! :rolleyes:

My main issue is that using the phrase "to the ogive" is too vague, and is not clear that what you are referring to is the point on the ogive where your bullet contacts the rifling in your rifle, the way you measured it.

I think Uncle Nick did a great job of illustrating that point in his drawing. The ogive is clearly identified on the bullet (showing the entire length) and on the cartridge identified as "ogive overall seating length from bullet comparator".

I see a difference there, and I think it should be reflected in the terms used in technical discussions.

I also think Uncle Nick nailed it. JHP is a physical description of the bullet construction. XPT is a Hornady name for one of their lines of bullets.

Of course, I come from a place where Pluto is still a planet and rabbits are still in the rodent family, so, there is that....:D
 
cdoc42 said:
I have always labeled my handloads, "OAL-OG" which I interpret to me at a later date or to those looking over my shoulder, as, "OverAll Length to the Ogive.
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One definition that seem appropriate for ogive: (from Wikipedia)
An ogive is the roundly tapered end of a two-dimensional or three-dimensional object.
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So, when I receive a round labeled "OAL-OG" , just where on the curve do I go to measure that OAL? What do I compare it to so I can tell if it is appropriate for my chamber/throat/barrel?
 
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