Underwood 357 Sig 125gr at 1511 fps!!!

Discussion in 'Caliber Corner' started by Police Marksman, Oct 15, 2012.

  1. SCmasterblaster

    Millennium Member

    That ISP info is good news to me.

    Wanna kill these ads? We can help!
  2. I wish Underwood would make this same round with the Sierra bullet. I do not know the demand, but it would really perform like the 357 mag and the ammunition that was used, SJHP. I would not use Hornady XTP's because I do not think they would perform well at those velocities. Below is the typical 125gr Mag performance of this type of round.


    The expansion may not be much compared to FBI protocols, but the FBI had much success with this round in the 357 mag. My 1,500 Sierra's from DT would probably give the performance as what is shown for the Federal 125gr Mag. What say you Kevin, make 357 sig with cup and core bullets??

    You might say just buy DT. Well, I do not like DT and he only sells them in 20 rounds boxes for $35.

    #42 PghJim, Oct 20, 2012
    Last edited: Oct 20, 2012
  3. SCmasterblaster

    Millennium Member

    Yes indeed, Sierra makes good bullets.

  4. The XTP designed for the .357sig would probably hold up decently but the 9mm XTP will not. The .357sig XTP is not available to reloaders though. In addition to the Sierra the 124gr Nosler might not do to bad. The HP cavity on the Noslers is somewhat small and the desing is pretty tough.
    #44 dkf, Oct 20, 2012
    Last edited: Oct 20, 2012
  5. SCmasterblaster

    Millennium Member

    I'd handload my 9mmP CCW rounds with the Sierra 115gr JHP. It is a great bullet. :cool:
  6. M 7

    M 7


    Out of curiosity, I put his test data (0.567"/125.3gr/1511fps Pen = 15") through the Schwartz bullet penetration model found in Quantitative Ammunition Selection and came up with a penetration depth of 15.4 inches.

    Looks like the SimTest stuff is a pretty close match to calibrated ordnance gelatin. :thumbsup:
    #46 M 7, Oct 20, 2012
    Last edited: Oct 20, 2012
  7. NEOH212

    NEOH212 Diesel Girl

    I'd like to see someone get a box Ranger T-Series ammo, pull the bullets and load them to these velocities and see the results.
  8. I didn't know Hornady made specific XTP bullets for their .357sig loads. I have both the 124- and 147-grain XTP rounds in that caliber and it's good to know Hornady isn't using their 9mm bullets in the cartridges.
  9. Like unit, I did not know that Hornady makes a special XTP for 357 Sig. Can you tell me more, prodoct code, etc. I know you said not for loader, but I am interested and will call Hornady if I knew the correct bullet. I have a load for my 38 Super that goes almost 1,500fps and I did not want to use the 9mm XTP.
    #49 PghJim, Oct 20, 2012
    Last edited: Oct 20, 2012
  10. Whatever the product number is for the .357sig 124gr XTP Hornady Custom load is, that is what had the different non 9mm bullet. I only have first hand experience with the 124gr XTP factory loads. I am currently out of them, shot them all. I bought several 100ct boxes of 90gr, 115gr and 124gr XTPs and they all have a different nose shape and HP cavity than what cam loaded in Hornadys 124gr sig ammo.

    Speer GD 53918 (left) Hornady Custom 124gr XTP .357sig factory load (right)

    Speer GD 54234 (left) Hand Load 100ct boxed 124gr XTP (right)

    The 9mm version that comes in the 100ct boxes for reloaders obviously has a smaller metplat, more side angle and the hp cavity is deeper and more cone shaped. The .357sig XTP is closer to the shape of the GD with a larger metplat and a shallower more dish shape hp cavity. Also notice the cannelure on the sig XTP which the 9mm version does not have. The cannelure helps to hold the jacket together. The sig HST bullet has a cannelure as well.
    #50 dkf, Oct 20, 2012
    Last edited: Oct 20, 2012
  11. Are you saying that on the top picture, the bullet on the right is the Hornady bullet for 357 sig?
  12. Yes.

    Ten minimum.:upeyes:
    #52 dkf, Oct 20, 2012
    Last edited: Oct 20, 2012
  13. Glock19Fan

    Glock19Fan Cool Guy

    The serrations on the .357SIG XTP also seen shorter, but deeper.

    I wonder if the bullet shape effects reliability of the cartridge?
  14. Thanks for the photos. I pulled out my two Hornady .357sig ammos and the Fiocchi 115-grain 9mm Extrema XTP rounds and compared them.

    Both the Hornady .357sig rounds look exactly like the .357sig rounds in your photos and have the cannelure while the 115-grain Extrema has a straighter, narrower profile like the 124-grain factory round you show without the cannelure. And the cavity in the 9mm XTP is deeper than the cavities in the two .357sig XTPs.

    I'm really happy to know I've got a 147-grain round specifically designed for .357sig. No wonder tnoutdoors got over 16" penetration when he tested it.
  15. shotgunred

    shotgunred reloading nut

    How about showing the used cases. Are the primers flattened?
    Are the cases bulged?
  16. Great review and that is a great load, I have a box.
  17. The primers will be flat even if the pressure was only 30,000psi. On Glocks an indication would be primer flow back into the striker slot on the breech face, and the appearance of the striker mark. If the striker marks start to, or completely disapears it could be a sign of excessive pressure. I have found this to be the case even with hard primers like CCI.

    Additionally, can you insert the fired casing back in the chamber and pull it out with only your fingers. If the fired case will not come out without prying or putting a rod down the barrel, it could be a sign of over pressure.

    A bulged case would be an indication of a barrel without full support, although if the pressure is real high the case may bulge. I would expect to see other signs also.
    #57 PghJim, Oct 21, 2012
    Last edited: Oct 21, 2012
  18. You should see what the primers look like on the Speer factory .357sig Gold Dots. Flatter than a pancake. They are soft unplated brass primers. So I don't put too much faith in reading primers but I can somewhat tell the difference on my reloads which all use the same primers.
    #58 dkf, Oct 21, 2012
    Last edited: Oct 21, 2012
  19. I shot this Underwood load in comparison to a box of federal 125gr. I cut afederal 5" group @ 10 yards to 2" using the Underwood. I spoke to the owner, Kevin Underwood and he said that his business plan is to deliver a premium ammo that delivers better energy dump and expansion at a price that is less than the "premium" manufacturers.

    He has great customer service. I screwed up an order and he fixed it for me at no charge.

    Accurate, loaded to what the 357sig should be, and great CS. I'm a fan.

    No case bulging or smileys.
  20. Check out the vid by tn9outdoors on their 10mm load & you will love the results.

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