GTA
All Springer/NP/PCP Air Gun Discussion General => Projectiles => Topic started by: JungleShooter on January 10, 2021, 04:50:44 PM
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Hollow Point Pellets – Specs & Performance Chart
Hollow point pellets – let’s shorten that to HP (and hope they still will expand on impact 😊).
Some….
• Some swear by them.
• Some swear at them.
• For some they are a great way to sell more pellets.
• For some they are a great way to justify buying more pellets.
• For some they are an effective way to end others’ lives.
• For some they effectively ended their own life.
🔴 The attached PDF will answer some of the following questions:
❓ There are so many hollow point pellets out there...: How do they compare??
❓ If I’m interested in trying HP pellets in my gun...: With which ones should I start testing??
❓ HP are about EXPANSION of the HP cup in order to do more tissue damage...: How far could I shoot a certain HP pellet and still expect expansion (given the power of my gun)??
Or: How much power would I need in order to shoot a certain HP pellet (and still get expansion)??
❓ Some HP are really long and might not fit into my magazine...: How long are the long ones really??
To make this HP Pellet Specs & Performance Chart more useful, I gathered some ballistic background to help you draw good conclusions from the chart.
🔴 Which HP projectiles expand better to make a Better HOLE in the quarry? –– The faster, softer HP projectiles with larger, deeper HP cups, and expansion aids
Bob Sterne (HardAir Magazine and GTA) published some very insightful articles and posts on this subject (cf. sources*). Here are some points I have learned from Bob’s excellent discussions and elsewhere:
(1) Higher impact velocity – this seems to be the most important requirement for a HP expansion. To state it simply but with a lot of oversimplification:
• Most .22cal HP pellets expand above 800fps.
• Many expand between 700 and 800fps.
• Few expand between 600 and 700fps (at least not by much).
• Many .22cal HP slugs seem to need somewhat higher impact velocities for expansion, as their HP are often rather narrow.
However, each projectile has a different mix of characteristics that facilitate or hinder expansion, as the following points show. Therefore, a better assurance of expansion offer tests in suitable ballistic mediums including actual quarry. I have collected test results from the forums and YouTube and you can find them on two separate threads.
(2) Softer lead (i.e., purer lead, with less antimony mixed in, like the pellets from JSB, and like most slugs [NSA, H&N, etc.]; HP projectiles made from tin alloy are extremely unlikely to expand [e.g., Gamo PBA Armor])
(3) Wider HP cup (e.g., H&N Crow Magnum, Crosman Destroyer – vs. – JSB UltraShock Heavy)
(4) Deeper HP cup (e.g., H&N Baracuda Hunter – vs. – H&N Terminator)
(5) Thinner walls of the HP cup (often the wider cups have thinner walls)
(6) Slits (= predetermined tearing points) that aid the HP to open up in petals function as expansion aids (e.g., H&N Terminator, Crosman Piranha)
(7) As another expansion aid serves an object that fills the HP cup with a different material that upon impact will push into the hollow point and aid in its expansion. This design is used for the HP with “ballistic tip” – this currently would include some of the following HP (in .22): JSB (Predator): Polymag, Polymag Short, Metalmag. H&N: Hornet. Skenco: UltraMag Metal Tip. Crosman: Gold Tipped. Gamo: Red Fire, Gamo Rocket, PBA Armor. The Gamo Rocket and the PBA Armor use a BB (a copper ball), similar to how Griffin designs their LDC slugs with a polymer ball, and Lead Fist Slugs with a steel ball.
Some poster have suggested to fill hollow point cups with a drop of superglue or another malleable but hardening substance; I’d be interested in seeing comparative tests in ballistic gel or DIY gelatine to prove their effectiveness!It seems that this tip would be aerodynamically more favorable than a wide open hollow point cup, so the increased BC would aid in velocity retention resulting in higher impact velocity for better expansion.
(8 ) When projectiles tumble and flip inside the quarry they make a bigger HOLE then if they just went straight ahead. This tumble could be induced when the ballistic tip is being torn out of its seat in the pellet, or when the pellet hits a bone.
(9) Fragmentation is rare with typical pellets and slugs at typical impact velocities. Each fragment – if still with enough energy(!) – could make its own wound channel, increasing the permanent wound cavity.
(10) Harder impact material will cause the HP to expand wider. The ballistic mediums used in many expansion tests in the forums and on YouTube are often much harder than animal flesh: play-dough, modeling clay, water (at high impact velocities), hard soap. Therefore, the most realistic expansion tests would be using calibrated ballistic gel (10%), which is the ballistic medium that the FBI trusts for their terminal ballistic tests, rather than any of those harder materials that give too optimistic expansion results.
🔺 Attachment at the end
💀 There is more to the killing game.... – This thread is PART (3) of a four-part series, here in logical order and with links to each:
● PART (1) Quarry: What kills’em dead – the Mechanics of Killing
• What kills is a Permanent HOLE in the quarry – nothing else. Only crushed tissue kills, not “energy dumped,” nor a “temporary wound cavity,” nor “hydrostatic shock.”
• For the HOLE to kill – it must be in the right place in the quarry: brain/spine or heart/lungs or arteries/veins (to cause hemorrhaging).
• The projectiles that make a Better HOLE in the quarry are –– larger, faster, bulldozer-nose, expanding projectiles.
https://www.gatewaytoairguns.org/GTA/index.php?topic=182421 (https://www.gatewaytoairguns.org/GTA/index.php?topic=182421)
● PART (2) How Much Hollow Point Expansion Does How Much More Damage?
• A larger projectile makes a larger HOLE.
• So, how much larger is the HOLE if I go from .177 cal to .25 cal? (results in Table 1)
• And how much larger is the HOLE if my hollow point projectile expands 1/10 of an inch? Or 1mm? (results in Table 2)
https://www.gatewaytoairguns.org/GTA/index.php?topic=182422 (https://www.gatewaytoairguns.org/GTA/index.php?topic=182422)
● PART (3) Hollow Point Pellets – Comparison of Specs & Performance
[The current thread.]
● PART (4) Hollow Points – Testing How Much They Expand and How Far They Penetrate
Every hollow point projectile (pellet or slug) performs differently, in line with its specs and the conditions. Find a collection of Projectile Expansion and Penetration Test results for both HP pellets and slugs.
(4a) HP Pellet Projectile Expansion and Penetration Tests
https://www.gatewaytoairguns.org/GTA/index.php?topic=182425 (https://www.gatewaytoairguns.org/GTA/index.php?topic=182425)
(4b) HP Slug Projectile Expansion and Penetration Tests
https://www.gatewaytoairguns.org/GTA/index.php?topic=182427 (https://www.gatewaytoairguns.org/GTA/index.php?topic=182427)
I hope this will be helpful to some!
Matthias
🔴 Attachment:
HP Pellet Specs & Performance CHART. 152.pdf [/b]
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Holy data dump, my head may explode.
Good post, I clearly need more powerful guns. If I understand the FPE chart, not sure I do, nothing under impact of 13.8 could expand?
When looking at the super H, why are there fields with no data. Sorry, I am a little slow, most of the time.
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Good post, I clearly need more powerful guns. If I understand the FPE chart, not sure I do, nothing under impact of 13.8 could expand?
🔶Kurt, after making the chart I came to the same frustrating conclusion.
➔ To shoot hollow points that still expand at longer ranges — I need more power....! 🙄
🔶To get any kind of useful expansion other than tobacco spitting range with a .22 pistol, it better be hot-rodded and without noise sensitive neighbors around.
🔶Note, however, that the impact velocity ranges in the Chart are general guidelines — every pellet is different.
For instance, the Crosman Hollow Point seems like a good candidate for expansion because it is light and has a high BC (for a HP). But many tests disprove that, even above 800fps impact velocity.
The Chart can guide you to select pellets that are most likely to expand within the ranges and with the gun you are interested in.
Then you'd need to test the precision of these pellets (if your gun "likes" them at that range and with that power).
Matthias 😊
PS: I left certain table cells empty because it did not seem worthwhile to calculate them.
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Oh, again, GTA is not allowing me to edit my own posts ::) -- time limit of 20 or 30 minutes after posting just doesn't cut it for me.... Not by a long shot....
So, I have to post this separately, the sources for some of the stuff I wrote in the OP:
*Sources:
Matt. (2019). Terminal ballistics: How bullets wound and kill. Retrieved from the Everyday Marksman website, at https://www.everydaymarksman.co/marksmanship/terminal-ballistics/ (https://www.everydaymarksman.co/marksmanship/terminal-ballistics/)
Fackler, Martin L. (1988). Effects of small arms on the human body. Research Report. Letterman Army Institute of Research, Division of Military Trauma Research. Retrieved from https://web.archive.org/web/20120218212956/http://ammo.ar15.com/project/Fackler_Articles/effects_of_small_arms.pdf (https://web.archive.org/web/20120218212956/http://ammo.ar15.com/project/Fackler_Articles/effects_of_small_arms.pdf)
Arborelius, Ulf P. (1999-2013). Shooting holes in wounding theories: The mechanics of terminal ballistics. Retrieved from http://www.rathcoombe.net/sci-tech/ballistics/wounding.html (http://www.rathcoombe.net/sci-tech/ballistics/wounding.html)
Newgard, Ken. (1992). The physiological effects of handgun bullets: The mechanisms of wounding and incapacitation. Wound Ballistics Review, 1(3): 12-17. https://drive.google.com/drive/folders/0B_PmkwLd1hmbd3pWYVVJeGlGaFE (https://drive.google.com/drive/folders/0B_PmkwLd1hmbd3pWYVVJeGlGaFE)
Hollerman, J. J., Fackler, M. L., Coldwell, D. M., & Ben-Menachem, Y. (1990). Gunshot wounds: 1. Bullets, ballistics, and mechanisms of injury. American Journal of Roentgenology, 155(4), 685-690. https://www.ajronline.org/doi/abs/10.2214/ajr.155.4.2119095 (https://www.ajronline.org/doi/abs/10.2214/ajr.155.4.2119095)
Schaefer, John C. (2014-2018). Terminal ballistics. Retrieved from http://www.frfrogspad.com/terminal.htm (http://www.frfrogspad.com/terminal.htm)
and http://www.frfrogspad.com/terminal2.htm (http://www.frfrogspad.com/terminal2.htm)
Gateway to Airguns. (Ed.). (2018). Hunter’s terminal ballistics. [Thread]. Retrieved from https://www.gatewaytoairguns.org/GTA/index.php?topic=148277 (https://www.gatewaytoairguns.org/GTA/index.php?topic=148277)
● Some of Bob’s excellent articles on airgun terminal ballistics (some are about slugs but the principles are similar for pellets): Sterne, Bob [rsterne]. (2020, Apr. 15). The effect of caliber on airgun pellet performance. HardAir Magazine. Retrieved from
https://hardairmagazine.com/ham-columns/the-effect-of-caliber-on-airgun-pellet-performance/ (https://hardairmagazine.com/ham-columns/the-effect-of-caliber-on-airgun-pellet-performance/)
Sterne, Bob [rsterne]. (2020, Jun. 22). Bob Sterne discusses hollowpoint slug design. HardAir Magazine. Retrieved from https://hardairmagazine.com/ham-columns/bob-sterne-discusses-hollowpoint-slug-design/ (https://hardairmagazine.com/ham-columns/bob-sterne-discusses-hollowpoint-slug-design/)
Sterne, Bob [rsterne]. (2020, Mar. 17). Airgun pellet penetration – the real story. HardAir Magazine. Retrieved from https://hardairmagazine.com/ham-columns/airgun-pellet-penetration-the-real-story/ (https://hardairmagazine.com/ham-columns/airgun-pellet-penetration-the-real-story/)
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Thank you for this Matthias. I know I put up a few hollow point pellet photos somewhere when I blasted them into clear glycerin soap slabs several inches thick with a 30fpe PCP, and then cut out the deformed pellets to show the over-the-top expansion, they were alien-cool looking after being forced into the soap... ;D
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I did a little more testing and included a Gen Ii Hp slug that found its way thru a pest squirrel. @ 65 yards. LOL It mic' just shy of .60"
Next the Shredder as Motor Head named it. Man it blows things up!
Glue (Silicone head gasket material). In Pb rounds, they are designed to not fill with debris from say denim or heavy winter clothing and still be able to open. It does not add to the openuing effects in normal use. In fact, slightly restricts expansion.
Hp without glue in cavity, Gen I
And finally, the Gen II 27 gr slug for the pp-700 at 470+ into water jug at 50 yards. All others other than the Squirrel were at 80 yards.
As you can see, a HP can be made to perform well under the 700 fps thresh hole often quoted. ;)
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Oop's two got skipped. Here is the same slug without the glue in the cavity. Same distance, same slug, same fps.
As you can markedly see, it is substantially better in expansion. 8)
I have tried a variety of inserts in the cavities, plastic beads, small bearings, different soft and hard glues and waxes. Always the same. The NON filled are more effective by quite a bit.
Knife
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Knife, 👍🏼
very interesting, your findings that a HP cup without the filling (glue, gasket maker etc). expands better! 👍🏼
I read a thread where people proposed the filling as being better for expansion. Guess a side-by-side test, same conditions, into a realistic ballistic material (dead squirrel, or ballistic gel) would give the final proof. 👍🏼
The squirrel slug is one from your own production, correct? So, not available to the average Joe (or average Matthias), correct? 😊
I was going to try the philips screwdriver slug mod this week, but so far no time.... I really want this to work on pigeons! 😄
Matthias
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Knife, 👍🏼
very interesting, your findings that a HP cup without the filling (glue, gasket maker etc). expands better! 👍🏼
I read a thread where people proposed the filling as being better for expansion. Guess a side-by-side test, same conditions, into a realistic ballistic material (dead squirrel, or ballistic gel) would give the final proof. 👍🏼
The squirrel slug is one from your own production, correct? So, not available to the average Joe (or average Matthias), correct? 😊
I was going to try the philips screwdriver slug mod this week, but so far no time.... I really want this to work on pigeons! 😄
Matthias
Yes, my own make of slugs. More testing needed, but is very work intesive. Perhaps I can furnish them in the future.
the phillips helps begn expansion. It is the start of what I do to the slugs. I only use it for an indexing guide for the actual work. ;)
I did provide side by side pic's of the glue, no glue. Just the sequence got screwed up. ;D
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Glue=
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No Glue. Same slug, same fps, same type 1 gal water jug 80 yards.
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Thanks for the clarifications, Knife! 👍🏼
Yeah, the non-filled slug peeled back waaaay more than the filled slug.... 😄
If you do start selling your slugs, let me know! I'll gladly add you to the Slug Table (.22) I made for the forums to easier compare the available options for sizes and weights! 👍🏼
As airgunners we truly live in amazing times! The options are vast! The fun is maximized! 😄
Matthias
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Will Do Sir! and Thank You!
Knife
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This is at 39 yards with gamo redfire. Also have meat tests like Paul Harrell channel but for air rifle lol. In my experience I don't use hollow anymore (hades) I found it looses way more energy down range than fx 10.3 pellets same weight. Hit some squirrel and some crow center mass & had enough life to hide behind something still. So I stick to the most consistent pellet . The Fx 10.3 and take head shots. Of coarse the bigger bores hunt bigger game so different results. Here's 1 screen shot of the Gamo redfire. Have videos of h&n hornet on YouTube with Baracuda hunter extreme and hades test following.
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.22 springer into homemade billistic playdough
Crosman hp then crosman piranha then hunter domed
Lot of shock value of the HP vs even the phanha. I tested it 3 times to make sure it was not a fluke.
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Link
youtu.be/my_VwWQ-r8I