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FPE needed to deform a pellet???

How many FPE are needed to get a pellet to deform…?

I’ve often wondered why pellet manufacturers don’t make softer “hunting” pellets, from softer lead, which will deform, mushroom and dump all their energy into the target, there by helping with hydrostatic shock, making bigger holes, doing more damage to vital organs etc and lessening the chance of a pass through and the possibility of damaging things behind the target (I’m thinking about pest control here).

So I tested some .177 pellets in my sons little Gamo Delta Fox.
I tested some 8.44gr JSB exacts which leave the muzzel at 451fps producing 3.8FPE.
I also tested some JSB Hades 10.34gr which will be slightly slower, but probably produce about the same fpe, let’s call it 4FPE.

The results were the same for both.

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At these very low powers, the pellets completely deform and turn into smarties, or M&M’s for those who don’t know what a smart is.
Imagine if they performed the same way hitting a rat or a starling!

So, is the lead soft enough??? With 3.8FPE a steel plate at 10m completely flattens a pellet, but a rat or bird dosent provide enough resistance to get the pellet to deform and dump energy. They usually pass through pretty much unchanged. Are our pest targets too soft?

I think we need softer pellets for close range hunting/pesting.
Yes I know velocity is a major factor, those same 10.34gr hades at 950fps will mushroom going through a rat, but that rat better be standing in an open paddock, with at least another paddock behind that one, because ur never going to see that pellet again…
Same pellet and same rat in a milking shed… hummmmm 🤔
And yes of course pellet shape also plays a huge role in how that pellet performs, mushrooms and dumps energy. I wish they could make a soft hollow point pellet that groups as accurately as a domed pellet, mushrooms to twice the caliber, dumps all its energy and ever exits… 🤔

Does anyone have an even lower powered air rifle/pistol so we can continue testing?
Try keep it .177 and steel plate pellet trap at 10m, and for the sake of continuity try use Exact and Hades if you can.

Pete.
 
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2.5 FPE is where you will start to see some mangled and flattened pellets. The kinetic energy starts to increase beyond the said power threshold. The amount of kinetic energy is far greater than the material yield strength. that's why you start to see such dramatic deformation. Actually, the deformation is subjected to force applied on a unit area, so if you impress a nail on the pellet the force acting on that small unit area is greater than its shear strength. But to answer your query 2 FPE and greater. anything lesser will have a less dramatic deformation. The pellet stop is considerably more rigid as compared to lead, if it was made of aluminum or something softer, you would have noticed a less degree of deformation.
 
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I see no correlation between what a pellet looks like after being shot into a metal pellet trap and what it looks like after hitting an animal. I'll attach a pellet that went from behind the near shoulder through the opposite shoulder stopping under the skin. It broke the off side shoulder. Range was only 12 yards and it was launched at almost 900 fps. It's a 10.65 grain H&N Baracuda Match. The picture is not great but the pellet doesn't look anything like your trap pellets. FPE at the muzzle was about 19 fpe. I think it would have gone through if it had not contacted the off side shoulder but would not have had much velocity/energy left. I like having an exit hole because the animals seem to die quicker. The 13 ounce female that took this pellet took a step or two and collapsed.

I shot a squirrel once with a low velocity pump up 177 that makes about 5 fpe and will not do it again. The pellet did not make it through the near side shoulder and the squirrel died a slow death (took days).

If you are worried about energy after exit what do you do about misses? You need to shoot only in directions where the pellet will land safely. If you do that, pass throughs are not an issue. But still you can minimize pass throughs by using guns 12 fpe or a bit more. But I would avoid body shots until you get up around 18-19 fpe. You need reliable penetration. In my experience, you do not need expansion. Even a 177 will drop them quickly and reliably if you just put the pellet into the vitals.

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Most of my shots with my 32 fpe P35-22 and P35-25 have passed through. I shoot non-expanding H&N pellets in both. The 25 likes H&N Field Target Trophy which are only 20 grains. Muzzle velocity is about 875. It's killed 18 squirrels and 15 were pass throughs. Two were shots to the front of the chest and stopped behind a rear leg. Those were the only two that ran and the furthest one went was about 15 feet. The other one that stopped in the squirrel was a double shoulder hit. That squirrel dropped immediately. The P35-22 likes 21 grain H&N Baracuda Match and has only killed 5 squirrels for me. All where pass throughs and all were DRT.

My Prod is tuned to about 18 fpe now and will shoot through a dead squirrel but only on an ideal side to side shot that doesn't hit a leg bone. So it normally doesn't pass through. Pass throughs are iffy with my 19 fpe 177. Looks like 2 of 6 stopped in the squirrel and 4 passed through. I don't know exactly where the cross over is but I'm guessing 25 fpe in a 22 would pass through a lot of the time. With simple domed pellets.

Expanding pellets penetrate significantly less in wet paper and I think in animals too - if they expand at all. Crosman HPs rarely expand. But Metal Mags expand even at Prod velocity. But penetration is greatly reduced. Could be a good thing, I guess, but I think they should be used in guns with plenty of fpe for the animal being hunted. Not Prods. Maybe in my 32 fpe 22. But when domed pellets regularly result in DRT kills, I don't see a need for expanding pellets.
 
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Testing media is pretty crucial when trying to review terminal ballistics. I think using FPE as a measuring metric is probably not best, since velocity (at impact) is what makes the difference. Lead pellets are already pretty soft when it comes to lead alloys. Most of the testing with ballistics gel I have seen show most pellets wont deform slower than ~800 at impact. There are so many variables though such as design, twist rate rpm, exact point of entry and what a pellet might travel through, etc. But the Hades seems to deform better at slower impact velocities compared to most other designs, including other hunting style pellets. And sometimes deforming doesnt matter, such is the case with the bigger Hades in 25/30cal. They dont really deform as well, but I think they tumble better in a squishy target and allow a lot of hydrostatic shock as a result. This topic is much more complicated than anyone on this forum can really fully understand. Humans have been testing/studying terminal ballistics for like 300 years and its still mysterious.
 
Pellet trap is MUCH harder than the pest, and it weighs a lot more... not a realistic comparison to measure solid metal vs. rats/starlings. An empty soda can would be a better analog. Punch a hole in the aluminum can and you will wreck a rat.
I tested my new Big Bang Pellet trap at 25 yards with my .25 Maverick and 33.95 pellets at 890fps, let's just say the pellets turned into dust
 
Yeah, it would be a dream come true if pellets at 4FPE flattened in animal flesh like they do on steel traps! 😄


For the past couple of years I have been collecting hollow point expansion data from the internet (and I started my own testing on carcasses in .22cal).
Unfortunately, many tests I find use ballistic material very different from animal flesh... — play-dough, water jugs — all materials that assist expansion more than flesh.

🟠 Here are two of several dozen test results I have found since. The first one is by Rick Eutsler (AirGun Web TV) and is simply the best model of how to do this type of testing.

The second test was done by Steve Scially (AEAC), again, a trustworthy tester. It shows the expansion performance of several slugs.


🟠 The critical factor for expansion of hollow points is the impact velocity (IV) — not the muzzle velocity, nor the impact energy. Typical .22 HP pellets seem to expand reliably above 800fps IV. Between 700 and 800 it's a hit or miss, depending on the pellet design and the softness of the lead. Below 700 there are few HP that will expand... a little... maybe.

Matthias



Projectile Test. PT050.  Rick Eutsler (AirGunWeb) (2016). -ClearBallistics.com Gel.- 9–36FPE. ...jpg



Projectile Test. PT026.  Steve Scialli (AEAC) (2020). -Ballistic Gel Calibrated.- 41-46FPE. Bc...jpg
 
My r9 .177 shooting cphp 7.9 hitting this junk thin metal backstop at 100y



Now straight shooters our take chart shows cp 7.9 only having like 8 fpe at 50y. So i figure that at 50y a 100y mist be close to -0- ..lol.

Kinda looks enugh to put dents in and mash pellets to me for light 7.9 cphp's

The jole more likely from repetitive hits over time .. cause i know not strong enough at 100 to Peirce a crosman tin through...
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Random picked up under the rack
cphp.177deformed,100y.jpg
 
Thinking on this some.

I take a fiber filled pillow , a thin pladtic container of water, a pan of clay ,( like above) and a 3/16 steel plate set up at let's say 50y for example sake.

I shoot each one and inspect the pellet

The pillow one just has rifling marks and near reshootable the water jug is just showing some compressing, the clay one even more compressed say 1)2 mushroomed , but the steel plate is pretty splat flattened. So same gun , same pellet ,same fps, same energy, same yardage .
4 different results .. from near nothing to catastrophic..lol.

Seems pretty much what it hits mostly