Page 14 of 14 FirstFirst ... 4121314
Results 131 to 139 of 139

Thread: .38 double wadcutter load

  1. #131
    Site Supporter
    Join Date
    Jul 2016
    Location
    Away, away, away, down.......
    Quote Originally Posted by pettypace View Post
    Send me yours. I'll test it for you.
    If you’ve got a place to test it I think I have an old dead iPhone 3 with with a case at the house I’ll send to you; as long as you post photos and results here. Let me confirm and if you’re interested I’ll pm you for a shipping address.

  2. #132
    Quote Originally Posted by Caballoflaco View Post
    If you’ve got a place to test it I think I have an old dead iPhone 3 with with a case at the house I’ll send to you; as long as you post photos and results here. Let me confirm and if you’re interested I’ll pm you for a shipping address.
    Sounds good! Could be a crowd-pleaser at next week's Snubbyfest. PM coming your way.
    Last edited by pettypace; 01-15-2020 at 02:15 PM.

  3. #133
    The R in F.A.R.T RevolverRob's Avatar
    Join Date
    May 2014
    Location
    Gotham Adjacent
    Quote Originally Posted by pettypace View Post
    Maybe... But the Lucky Gunner tests showed the 135 grain Gold Dots only penetrating 13.6" in C-B gel. With a calibration factor of 0.8 that translates to less than 11" in 10% ordnance gel. In Brassfetcher's testing in validated 10% gel, they were marginal, at best.

    Is there some documented testing where the short barrel Gold Dots do significantly better from a snubby?
    Significantly better from a 1 7/8” gun? No.

    Nothing does significantly better penetration wise than a target wadcutter.

    But there were some quality control issues with the GD a few years ago. Any GD that is <830 fps or so is not going to penetrate and expand it will usually just expand.

    The other load to consider is the Cor-bon DPX or Buffalo Bore load using the Barnes 110-grain bullet. Both of those lods need 1000 fps to expand and get ~13-14” of penetration.

    The +P lead hollow point gives fairly consistent penetration (clothing can turn it into just a big WC in effect) from a snub of 14-18”. If it expands it works well, if not - eh it still penetrates. Hence my continued use of the Remington version.

    The trouble with all .38 Special is the marginalness of the bullet weight, material, and velocity needed. I’ve thought of going to a monolithic penetrator like the Lehigh and calling it a day.

  4. #134
    Site Supporter
    Join Date
    Oct 2017
    Location
    Southern NV
    Quote Originally Posted by pettypace View Post
    Maybe... But the Lucky Gunner tests showed the 135 grain Gold Dots only penetrating 13.6" in C-B gel. With a calibration factor of 0.8 that translates to less than 11" in 10% ordnance gel. In Brassfetcher's testing in validated 10% gel, they were marginal, at best.

    Is there some documented testing where the short barrel Gold Dots do significantly better from a snubby?
    This was posted in the original .38 Snub thread from which this thread was born:

    DocGKR has posted this before

    .38 Sp Speer 135 gr +P JHP Gold Dot (53921), ave vel=856f/s
    BG: pen=13.1”, RD=0.56”, RW=134.5gr
    4 layer denim: pen=13.6”, RD=0.53”, RW=134.1gr
    auto windshield: pen=9.4”, RD=0.51”, RW=129
    Given that your .8 conversion factor is based on non-expanding projectiles, I don't think it would apply to a JHP.

    Even if your conversion factor is valid for non-expanding projectiles, and without actually testing with organic gel you really don't know, it probably applies only to your block of clear gel at that specific time.

    As as been pointed out by The Schwartz and others, the density and tensile strengths of clear gel blocks vary from lot to lot.

    Based on testing documented at Police One, it appears that reconstituted blocks behave differently from their first use. They also discovered their 4 blocks failed BB validation despite the manufacturer claiming the lot passed.

    I don't remember which forum, but someone reported clear gel wasn't as temperature stable as the manufacturer claimed as they got significantly different penetration at different gel temperatures. Don't know how rigorous his testing was and if it was really a factor of temperature or melting/re-using blocks or something else.

    If you read that 3 part series at Police One, they conclude clear gel is not a valid replacement for organic gel. They state: "There is no apparent “conversion” between data derived from 10% organic gelatin and the current version of the clear synthetic."

    Their "Road Ahead":

    It’s important to note that the clear synthetic manufacturer was unhappy with how their product performed in our test, which has inspired them to take a close look at their product and quality control practices. As of press time, the manufacturer is engaged in an effort to modify the formula of the clear synthetic gelatin to enable it to pass FBI calibration. They are also taking steps to improve their quality control and inspection protocols to ensure that their products will comply with FBI standards for ballistic gelatin. When these changes are complete, a follow-on test will be conducted to evaluate the performance of the upgraded product, and the results will be published here.

    For now, however, we’re not comfortable with having law enforcement officers and agencies make ammunition decisions, using FBI protocol criteria, based on the results of testing in the current version of the clear synthetic gelatin. As a result of this project, there may be a time in the near future when an improved formula makes the clear synthetic a suitable substitute for FBI calibrated gelatin, but we’re not currently there.
    ETA: I'm a little disappointed that this thread has come to: let's shot a duplex hand load through a cell phone into clear gel and report the results like they mean anything for self defense ammunition selection. That's the kind of derp I expect at THR or Cast Boolits or on YouTube....
    Last edited by SiriusBlunder; 01-17-2020 at 08:43 AM.

  5. #135
    Is there any accounting for the discrepancy between these results...

    DocGKR has posted this before

    .38 Sp Speer 135 gr +P JHP Gold Dot (53921), ave vel=856f/s
    BG: pen=13.1”, RD=0.56”, RW=134.5gr
    4 layer denim: pen=13.6”, RD=0.53”, RW=134.1gr
    auto windshield: pen=9.4”, RD=0.51”, RW=129
    ...and the results posted by Brassfetcher shown below:

    Name:  BF_gold_dots.jpg
Views: 296
Size:  16.3 KB

  6. #136
    Modding this sack of shit BehindBlueI's's Avatar
    Join Date
    Mar 2015
    Location
    Midwest
    Quote Originally Posted by pettypace View Post
    Is there any accounting for the discrepancy between these results...



    ...and the results posted by Brassfetcher shown below:

    Name:  BF_gold_dots.jpg
Views: 296
Size:  16.3 KB
    While I don't know, I would suspect the "discrepancy" is mostly block to block variance without normalization.

    Remember the gel is considered valid with a BB penetration of anywhere from 3.25" to 3.75", a roughly 15% difference in penetration from minimum to maximum. Obviously a shot into into a "3.25 block" isn't going to be exactly the same as a shot into a "3.75 block". The results would have to be normalized to be directly comparable block to block. Once that was done you'd be left with just lot to lot variances of the ammunition itself.
    Sorta around sometimes for some of your shitty mod needs.

  7. #137
    Quote Originally Posted by DMWINCLE View Post
    Given that your .8 conversion factor is based on non-expanding projectiles, I don't think it would apply to a JHP.

    Even if your conversion factor is valid for non-expanding projectiles, and without actually testing with organic gel you really don't know, it probably applies only to your block of clear gel at that specific time.
    You're right. Since the dynamic pressure produced at impact in the clear synthetic gelatin product will be on the order of 25% - 30% less than that produced in validated 10% ordnance gelatin, expansion occurring in the clear synthetic gelatin product will be commensurately less than that produced in validated 10% ordnance gelatin. The use of a scaling constant method is appropriate only for non-deforming/non-expanding projectiles but also requires larger sampling to confirm its insensitivity to changes in diameter and any fluctuations in the formulation of the clear synthetic gelatin product.

    Quote Originally Posted by DMWINCLE View Post
    As as been pointed out by The Schwartz and others, the density and tensile strengths of clear gel blocks vary from lot to lot.

    Based on testing documented at Police One, it appears that reconstituted blocks behave differently from their first use. They also discovered their 4 blocks failed BB validation despite the manufacturer claiming the lot passed.

    I don't remember which forum, but someone reported clear gel wasn't as temperature stable as the manufacturer claimed as they got significantly different penetration at different gel temperatures. Don't know how rigorous his testing was and if it was really a factor of temperature or melting/re-using blocks or something else.

    If you read that 3 part series at Police One, they conclude clear gel is not a valid replacement for organic gel. They state: "There is no apparent “conversion” between data derived from 10% organic gelatin and the current version of the clear synthetic."

    Their "Road Ahead":
    It’s important to note that the clear synthetic manufacturer was unhappy with how their product performed in our test, which has inspired them to take a close look at their product and quality control practices. As of press time, the manufacturer is engaged in an effort to modify the formula of the clear synthetic gelatin to enable it to pass FBI calibration. They are also taking steps to improve their quality control and inspection protocols to ensure that their products will comply with FBI standards for ballistic gelatin. When these changes are complete, a follow-on test will be conducted to evaluate the performance of the upgraded product, and the results will be published here.

    For now, however, we’re not comfortable with having law enforcement officers and agencies make ammunition decisions, using FBI protocol criteria, based on the results of testing in the current version of the clear synthetic gelatin. As a result of this project, there may be a time in the near future when an improved formula makes the clear synthetic a suitable substitute for FBI calibrated gelatin, but we’re not currently there.
    Counting the 3-part series by PoliceOne, those who've been able to discount both claims made by Clear Ballistics Gel, LLC that their product 1.) shear response-validates correctly and 2.) accurately represents the terminal ballistic behavior (specifically, post impact expansion and maximum penetration depth) of projectiles now consists of three independent sources:

    1.) PoliceOne/Mike Wood: https://www.policeone.com/police-pro...kEYB93TAd5o6J/

    2.) Brassfetcher/John Ervin: https://www.youtube.com/watch?v=5pqPBnSYTIc

    3.) TheChoppingBlock/Andrew Butts: https://www.youtube.com/watch?v=xJF-...ature=emb_logo

    Then, there are ''real-world'' examples of the clear polymer product being sold by Clear Ballistics under-representing terminal penetration depth on the 'net, like this one (seen from 0:08 to 0:12 in the video) produced by ShootingTheBull410—

    https://www.youtube.com/watch?v=czsd-v5sm3s

    —that show projectiles rebounding several inches rearward and coming to rest at a depth that is far shallower than their actual maximum penetration depth.

    In the specific case cited, the test projectile reaches its maximum penetration depth of 18 inches in the Clear Ballistics polymer product at 8 seconds into the video—

    Name:  1a.jpg
Views: 1126
Size:  21.4 KB

    —and then rebounds inside the temporary cavity to a depth of 13.5 inches where it remains at rest at 12 seconds into the video—

    Name:  2a.jpg
Views: 1117
Size:  22.3 KB

    —which constitutes a 25% loss of maximum terminal penetration depth all due to the insufficient physical-material response of the Clear Ballistics Gel product.

    The failure of the Clear Ballistics Gel product to correctly represent the temporary and permanent cavitation produced by projectiles being tested in it is due to the fact that the rheology of the Clear Ballistics Gel product (which is composed of a tri-block copolymer plasticized by a paraffinnic processing oil) has a very much lower strain-energy storage and loss modulus than does properly prepared 10% ordnance gelatin.

    This mechanical property deficiency is documented here:

    https://apps.dtic.mil/dtic/tr/fulltext/u2/a505788.pdf

    And here:

    https://www.arl.army.mil/arlreports/2006/ARL-RP-134.pdf

    This well-documented lack of material response properties in the Clear Ballistics Gel product results in the projectile rebound behavior seen in the video (and elsewhere in other videos) linked above.

    Furthermore, as the Clear Ballistics Gel product is recycled for re-use as is recommended by the manufacturer, the shear-response properties and the formulation of the product itself will change as volatiles in its composition are driven off during the ''remelt/recast process'' resulting in constantly changing physical-material properties of the Clear Ballistics Gel product. So, even if terminal ballistic testing is confined to any one given production lot of the Clear Ballistics Gel product, test results will also vary over the course of its use as that particular lot Clear Ballistics Gel product "evolves" during repeated recycling over its lifetime.

    Given the expense (approximately $130.00) of just one 16 in. × 6 in. × 6 in. block of the Clear Ballistics Gel product and its failure to live up to any of the manufacturer's claims that their product 1.) shear response-validates correctly, 2.) accurately represents the terminal ballistic expansion and penetration of a projectile passing through it, and 3.) its ability to be recycled without altering its physical-mechanical properties, there seems to be no real advantage to relying upon the Clear Ballistics Gel product for such testing unless one is merely interested in "shooting stuff just for shits and grins".

    The more closely the Clear Ballistics product is examined, the more issues come to light and all of it suggests that the product is a failure. I suspect that, so long as people are willing to buy the Clear Ballistics Gel product without questioning its technical relevance and accuracy, they'll keep selling it and the 'net will continue to be swamped with waves of this sort of testing. Even now, one need only look as far as one major online ammunition retailer who has invested heavily in published testing using the Clear Ballistics Gel product as an advertising program, to see that people are now relying upon dubious data obtained in the Clear Ballistics Gelatin product to decide what they will load and carry in their defense sidearms.

    What really concerns me is that if a manufacturer was marketing a projectile design for self-defense that failed to perform as advertised those testing it and observing the failure would be holding the manufacturer responsible for such a misrepresentation. Yet, no such response exists in the testing community when it comes to the Clear Ballistics Gel product.
    Last edited by the Schwartz; 01-17-2020 at 03:39 PM.
    ''Politics is for the present, but an equation is for eternity.'' ―Albert Einstein

    Full disclosure per the Pistol-Forum CoC: I am the author of Quantitative Ammunition Selection.

  8. #138
    Quote Originally Posted by the Schwartz View Post
    What really concerns me is that if a manufacturer was marketing a projectile design for self-defense that failed to perform as advertised those testing it and observing the failure would be holding the manufacturer responsible for such a misrepresentation. Yet, no such response exists in the testing community when it comes to the Clear Ballistics Gel product.
    Is anyone really holding the ammo manufacturers accountable for misrepresentation? If so, how did they miss this:

    Name:  hornady.jpg
Views: 350
Size:  46.9 KBName:  hornady2.jpg
Views: 334
Size:  49.9 KB

  9. #139
    Quote Originally Posted by pettypace View Post
    Is anyone really holding the ammo manufacturers accountable for misrepresentation?
    Sure. Performance issues with the relatively new 9mm Speer 147-grain G2 Gold Dot JHP have been addressed and rectified as a result of such testing that arose from wide-spread complaints that the G2 failed to expand after passing through barriers like 4LD.

    Quote Originally Posted by pettypace View Post
    If so, how did they miss this:

    Name:  hornady.jpg
Views: 350
Size:  46.9 KBName:  hornady2.jpg
Views: 334
Size:  49.9 KB
    I am not sure that it is seen by many as a legitimate self-defense option much like Hornady's Zombie Max line of ammunition. Of course, I would not want to have to explain in court why I was using something that could be used to suggest that I was delusional (because I believed in zombies) when acting in defense of me and mine. I also have a problem with the latest ammo-manufacturing design philosophy that suggests that ''we need to plug up a JHP's expansion cavity before it is plugged up and fails to expand", but that is a topic for another time.
    ''Politics is for the present, but an equation is for eternity.'' ―Albert Einstein

    Full disclosure per the Pistol-Forum CoC: I am the author of Quantitative Ammunition Selection.

User Tag List

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •