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6 pellet penetration/expansion test - Titan GP .22

November 26 2010 at 4:46 PM
Ray Andrew  (Login Ray280)
YF

Some new pellets, the Daisy Max Speed I found in my toolbox from years past. Shot from a Titan GP .22 at 10 meters into dense clay. Not scientific but some interesting results.

Notice the deformed (compressed) clay pattern in front of each pellet. The Predators have an expanding cone shape, while the Daisy flat nosed have the exact opposite. The pointed Daisy also have a contracting compression pattern.

[linked image]


Entry holes the Predators were cleanest and smallest, Daisy flat nosed was largest. Somewhat more expected result.


[linked image]

I put in the trigger mod and a Centerline 4x16x40 scope. Grouping at 10 meters is .38in with Predators, .42in with JSB's, .5in with Beeman Copper FTS. Hoping things will tighten up when I get more used to the gun. Only about 300 rounds fired so far.


    
This message has been edited by Ray280 on Nov 26, 2010 4:52 PM


 
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Terry in LP
(Login anuthabubba)
YF

Great stuff Ray!

November 26 2010, 4:53 PM 

The pictures are very revealing. Velocity numbers would make it extra kewel.


    
This message has been edited by anuthabubba on Nov 26, 2010 4:55 PM


 
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Ray Andrew
(Login Ray280)
YF

Thanks Terry, it was time to contribute after lurking so long!

November 26 2010, 4:58 PM 

I would like the velocities also, but have no chrony. Maybe next year.


    
This message has been edited by Ray280 on Nov 26, 2010 5:00 PM


 
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Lon
(Login bigbore)
YFOT

Interesting...

November 26 2010, 5:09 PM 

Nice test and pictures.

[linked image]

 
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ES
(Login lasabre)
YC

Awesome Job !!!

November 26 2010, 5:23 PM 

Thanks for taking the time.

 
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robert
(Login gubb33ps)
YF

Nice test

November 26 2010, 5:21 PM 

thanks for sharing. Does help decisions to do a little pellet performance testing. Don't down-play a soft lead WC pellet for short range pest killing, it seems to do nearly as good a job as the expanding pellets (just won't do it as distance increases).

 
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Ray Andrew
(Login Ray280)
YF

Exactly Robert- short range squirrels were the test motivation

November 26 2010, 5:30 PM 

My back yard is only 60ft deep. 35ft from my sliding door is my shed, which squirrels decided to chew a 10in hole in the corner of the roof. After I fixed that, another hole appeared in the door and jamb. Over $200 in materials and a full day to repair. 13 squirrels have "crossed over" since that day.


    
This message has been edited by Ray280 on Nov 26, 2010 5:33 PM


 
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Terry in LP
(Login anuthabubba)
YF

For years I used wad cutters...

November 26 2010, 5:39 PM 

exclusively for all ranges in the field, pesting and paper punching.

 
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robert
(Login gubb33ps)
YF

Zap 'em...

November 26 2010, 5:39 PM 

..stepped over the line between "game" and "pest". Close range/home use gets bonus points for quick energy dump and lower penetration.

 
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Ed Devlin
(Login edevlin)
YF

Very cool, I like these ballistic tests

November 26 2010, 5:26 PM 


 
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Tony
(Login Trojan1994)
YF

Very cool pics!!! nt

November 26 2010, 5:54 PM 





 
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M'hackett
(Login 22MK1)
YFOT

I'm going to do some of that myself

November 26 2010, 7:30 PM 

Kinney Drugs has Neutragena soap on sale cheap every few weeks. I want to do some testing at 25 yards where I can reliably shoot at the long ends of the 3/4" thick bars which are too thin to shoot unless I stacked a few of them.
Nice thing about them is you don't have to cross section of distort the cavity.

 
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Ray Andrew
(Login Ray280)
YF

Good tip

November 26 2010, 7:51 PM 

I'll try those for an R7 .177 test next time. Completely forgot about the see-through advantage.

 
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Ray Andrew
(Login Ray280)
YF

Can anyone explain the compression patterns please?

November 26 2010, 8:00 PM 

Other than the Predators probably making a larger exit, is there anything significant to be concluded from the compression patterns in front of the pellets? Does the cross section expanding or contracting cone shape in front of the pellets have any influence on energy transfer for FPE or other factors? I'm not a ballistics guy - just interested in learning from those who are.

 
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Herb1836
(Login Herb1836)
YF

Compression patterns

January 31 2011, 1:09 AM 

The salient point here is that the Predator pellet penetrates less because it dumps a lot of its energy in a shock wave rather than fictions tearing through. Notice how the Predator shock wave pattern is much wider than the other pellets.

The other thing that some experimentation will show is that the side walls on the head of Predator first flatten out into essentially a much larger in diameter wad cutter. Then the head folds back of the conical tail resulting in a reduction in diameter.

I've shot pellets into the edge of paraffin wax and seen the same sort of shock patterns. The bar is translucent, but the shock pattern results in a very noticeable white area when viewed with strong back-lighting.

I've also cast "ballistic" gelatin into cans and shot this with Predators. The shock wave would make the gelatin recoil in the can so much that the slug of gelatin would slide an inch forward out of the can. (AL beverage can).

The other thing in all of this is that it isn't just how fast the pellet is traveling at impact. It is also about how fast the pellet decelerates. So a dense medium like clay, wax, or soap bars will decelerate a pellet faster and hence exaggerate the mushrooming.




Regards,
Herb

 
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Joseph Tousignant
(Login joejeweler)
YF

Nice job,.....i wonder how a pellet like the Beeman Silver Bear hollowpoint....

November 26 2010, 8:10 PM 

.....might have faired in expansion testing,....especially
for close range backyard pest elimination. Pellets are much cheaper than
the preditors.....

 
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robert
(Login gubb33ps)
YF

So far...

November 26 2010, 9:09 PM 

..all the HP's have managed to expand if you drive them fast enough, even Silver Bears. the odd news is that SilverBears are a touch hard, and usually won't expand well unless driven fast and even then tend to blow the nose off. I haven't tried the .25 version (although right now are about the cheapest .25 pellet on PA site).

H-points tend to do the same thing, blowing the nose off and often leaving a do-nut of lead as the base drives though the expanded nose. Pretty neat effects at shorter ranges, but they doen't seem to ahve the BC to keep their vel. for long.

If you get the cheap hard lead CPHP's moving fast enough at impact, even they will expand a bit if you hit something large and solid enough.

CrowMags commonly don't group worth sour-snail-snot, but I've one .25 that likes them, and at least one 5mm that does.

Which leaves the Predators...considering some recent post, that seems a divisive issue on the board...which do expand and do seem to hold onto their speed better than the other HP's.

gamo's knock offs haven't managed to group well enough in any of my rifles to merit use at anything other than tobacco spitting range.

Are some others offered, but I've not tested them (yet).



    
This message has been edited by gubb33ps on Nov 26, 2010 9:11 PM


 
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robny
(Login robnewyork)
YF

seems the predators deliver all energy fast ,good on game ..nt

November 26 2010, 8:20 PM 


 
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Jim in SWMO
(Login jmhenrichs)
YF

Those are some great pictures.

November 26 2010, 11:45 PM 

I like the way you arranged them, too! It's interesting that the Predators had the smallest entry hole but showed the largest "shock wave" pattern. What did you use to slice the clay so as to not disturb things?

I did something similar to this last weekend with my .177 RWS 34 Pro Compact and some Duct Seal at 20 feet. I didn't slice it, though. Was mostly just checking penetration for lining a pellet trap and looking at the deformation of a few different pellets. The hollow point cavity of the Predator I shot into the Duct Seal expanded to about 1/4" and it completely shed the front ring leaving a lead O-ring behind. May try it again if I can find a way to slice it like you did.


"You've come far, pilgrim."------"Feels like far."
"Were it worth the trouble?"----"Ah, what trouble?"

 
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Ray Andrew
(Login Ray280)
YF

A slightly oiled cooking knife

November 26 2010, 11:59 PM 

The clay was from Hobby Lobby. The knife was a slightly oiled and wiped prior to samples, cooking knife. Worked great. Temp was 65 though which made it a bit stiff. Which was also why the clay cut so cleanly for the samples. The clay is more important than the knife.

[IMG][linked image][/IMG]


    
This message has been edited by Ray280 on Nov 27, 2010 12:03 AM


 
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