Home > The Armory > Caliber Corner > Underwood 357sig Under Rated Velocity

Underwood 357sig Under Rated Velocity

  1. Last week I chrono tested some Underwood 125gr Gold Dot ammo rated at 1475fps out of my G33 with a 4” KKM barrel. I only got an average of 1405fps in 10 rounds tested. There are dozens of chrono test results online, some even right on the Underwood site in the reviews, stating 1500+ velocities out of a 4” barrel. I have not seen any test results yet under 1500fps.

    My chrono is accurate. It’s been tested against other chronos. I tested my handload 357sig rounds that were under max load at the same time and they ran just over 1500. It seems I received a bad batch from Underwood?

    I contacted them and they responded a few days later that they test with a 4.6” barrel. For one, like I said before, everyone else is getting 1500 in a 4” barrel. And secondly, I found a post from 2018 where a person also contacted Underwood about the 357sig and asked what test barrel they use. Underwood responded that they use a 4” barrel. So I don’t know what to believe. Is it a bad batch? Did Underwood recently lower their recipe? Are they really using a 4.6” barrel now and therefore lowered their load?

    I've always been very happy with Underwood ammo, carried it for years, and their 9mm loads have always been right on with my chrono. Has anyone recently tested the 357sig load from Underwood? Curious if you are getting the same results
  2. Well I shot some of it at the range recently, indoors, out of an alpha wolf 4" fluted 357 Sig Barrel and it 'felt' like the advertised velocity, and 'felt' like FPE was 600, or greater. My statements are as accurate as the dodos on YouTube who don't have a trigger pull gauge and emphatically state what the trigger pull is on various firearms! [emoji6][emoji1]

    Sent from my SM-J337V using Tapatalk
  3. what type of rifling on the KKM barrel???...hasn't GLOCK always claimed their polygonal rifling gets them better velocity than other barrel makes rifling???

  4. so, we are talking about 1-1450/1500 = .03 or 3% difference?

    air temperature, barometric pressure, humidity, cartridge temperature all affect chronograph results. If you look at the TNoutdoors videos it was in the 90's and humid. What were your conditions? Also, humid air is less dense than dry air (O2 has a MW of 32, N2 has a MW of 28 and H2O has a MW of 18).

    And all this completely ignores difference in chronographs.
  5. KKM uses button rifling. I have never seen any difference in velocity between Glock OEM barrels and aftermarket.
  6. It's a 6.7% difference, 100fps, 1400/1500. It was 45F out, low humidity, not enough to drop 100fps. But like I said, I tested other handloads at the same time and they easily were over 1500. My weakest loads ran about 1400, same as Underwood. I have chrono'd Underwood's 9mm +P+ 1300fps load and it was right around 1300 with the same chrono, different day but similar temps in the 40's. My chrono is correct.
  7. You probably meant ft/s, not ft/min. Proofreading and the EDIT button are your friends. :)
  8. Yes fps. To my defense, I'm an engineer currently on a machine start up in Massachusetts. The machine runs in FPM, Lol. I'm so used to talking in FPM.
  9. Might have what folks call a "Slow Barrel" I have one Glock 17, my Range Monkey that is always a good 50 to 60 fps faster than my backup G17.

    Was the 1,500 fps shots done in the hot summer sunshine?
    Chronos can screw up and I have never had mine throw the exact same numbers as my buddy's but mine came over on the Ark.
    Underwood could have started using a full size pistol?

    I wouldn't freak out unless it went from 1,405 down to 1,305 and back up to 1,501 all in the same box or lot number.

    Now I am not you so please don't take anything I said the wrong way, but maybe also try another order of ammo in a couple weeks and test them, unless it's over pressured or squiby I wouldn't worry to much. :cheers:
  10. Highly unlikely coming out of KKM. Chasing velocity is a fool's errand.
  11. All loads where tested at the same time, my handloads at 1500 and the Underwood ammo. Like I said, my less than max handloads hit 1500 in the same barrel on the same range trip. Underwood did respond that they use a 4.6" barrel for testing. So to me that implies that they did indeed lower their load, because others have been getting 1500 in a 4" and according to one person in 2018, he said Underwood responded that they use a 4" test barrel. I did get 4 boxes and only tested one of the boxes. I'll test another box next time, but they are most likely from the same batch.

  12. I don't see bumping up .60 in barrel length making that much difference but stranger things have happened.

    Sorta makes me want to Chrono the new Bach of 147gr +p+ 9mm Underwood ammo I just got in a couple weeks ago, all mine have been around 30 fps faster than the box quoted speed.

    I have heard that with the bigger manufacturers like Winchester, Federal, Remington & such they set there loading machines a little on the soft side because they will "Grow" a bit as more ammo gets thrown. Makes me wonder if that is the same with Underwood now???

    Honestly I don't know. :dunno:
  13. Adam, why must everything be so complicated?! Them boolits musta' slipped outta' their cases a few thousandths due to expansion and contraction from changes in temperature during shipping, so all he's gotta' do is hammer them back in a little bit and I'm sure he'll get the velocity he's looking for.

  14. Nope, I checked them 1.125" on the head, LOL.
  15. I need to hit mine with a sledge ;)
  16. I can only go by what I've read but it seems to me that posted velocities of GLOCK type (polygonal) barrels have had higher listed velocities than more traditionally rifled barrels...but if you've actually measured them you have actual experience whereas I only can go by what I've read...

    thanks for sharing that,

  17. For carry ammo, stick with well-vetted, professionally-tested (not YouTube tested, think government LE testers) ammunition from well known manufacturers with large LE contracts. They have QC and oversight in place that guarantees it will perform as outlined in their LE contracts. YouTube amateur testers use substitute gels like SIM-TEST and Clear Gel that has no scientifically proven correlation with how a projectile acts in a human body like true organic 10% FBI-spec ballistic ordnance gelatin, and the controls in place by YouTube testers are not within spec, leading to unreliable results. They simply do not have or use the resources needed to do testing properly.

    Boutique manufacturers' ammo are not to be trusted with your life.

    Underwood uses projectiles like Gold Dots that are not meant to be driven at 1500 FPS. This leads to over-expansion and under-penetration (more likely not to reach vital organs in an attacker, especially at bad angles and heavy clothing), or the petals will peel back flat against the core resulting in a smaller-than-desired overall diameter and overpenetration.

    Velocity isn't everything, and it's even undesirable past a certain point. Ft/lbs of energy has no direct bearing on a projectile's effectiveness or what it does in tissue, it only is a measure of an object's ability to do work.
  18. ^^^^ Good Info. ^^^^

    I do use Underwood ammo quite a bit, and never had one problem with it but that doesn't mean doodly squat. The reason I get Underwood ammo for 95% of the time is to pop a Hog with, at least with a screwed up shot on a porker I can climb a tree.:eek:
  19. HOW DARE YOU! You wouldn't last 10 seconds in Caliber Corner posting something so accurate and logical. Those energy guys will put you on ignore, call you a troll and 9mm cultist, and report you to a moderator to get you banned.
  20. Thanks for the info and you are right on. I'm well aware of this and have done a lot research on the subject of bullet design and velocity, and even wrote a short article on it (not published yet). It's particularily true for 9mm, but not as much for 357sig. The GD 357sig is designed for 1350-1400 and has a shallower hollow point. The extra 100fps does not effect it that much, expansion is about the same. Not the same for say the 124gr GD 9mm. That can over expand easily. The thing is with the 357sig, people don't buy one to get 1300-1350fps. You may as well just stick to 9mm +P. People who buy 357sig want velocity. That's what keeps this round alive. I bought mine (actually I won this one in GSSF) expecting to have a gun that could do close to 1500fps. So the Underwood did 1405. I don't know why it's 100fps lower than everyone else, but in retrospect, it's not a bad velocity for that bullet, still in it's designed range and less recoil than would be at 1500. I can live with it, LOL.
  21. Especially since "ft/lbs" (feet per pound) is a physically meaningless combination of units. Energy is measured in units of "ft•lbf" (feet times pounds-force), and "lbf" (pounds-force) is not physically the same thing as "lbm" (pounds-mass). Those unfamiliar with these important distinctions tend to use the vague and ambiguous terms of pound or lb or lbs. :)

    I have seen gun-press books where the author uses the nonsense term "ft/lb" everywhere instead of the correct "ft•lbf". Editors should catch such embarrassing errors before publication, but they sometimes fail.

    The several varieties of Underwood 125-gr JHP have for years carried a velocity rating of 1475 ft/s, with barrel length and type unspecified. A batch that I chronographed ten feet in front of muzzle on a 85 F day at 600 ft elevation produced 1565 ft/s from my G31 4.5-inch barrel and 1410 ft/s from my G33 3.4-inch barrel.

    Although it has been reported that Underwood uses a 4.6-inch long Glock barrel for their 357SIG results, that seems unlikely.

    1. Glock makes no 4.6-inch 357SIG barrels. That is the length of G20 and G21 barrels.
    2. My measured values of 1410 ft/s from a 3.4-inch barrel and 1565 ft/s from a 4.5-inch barrel seem to indicate Underwood's stated 1475 ft/s velocity is coming from a 4.0-inch barrel.

    I have no doubts about Underwood's production quality. Loads I've used have always had the best shot-to-shot velocity consistency of any commercial handgun ammo I've ever measured. However, I do doubt the source of their advertised velocity values. They always seem conservatively less than what is actually produced. That makes the OP's report of measured lower than advertised velocity very remarkable. I've never experienced or read of such from any Underwood product.
  22. I purchased a G-32 after a couple of years' reading of the caliber's effectiveness, not due to a search for velocity. I learned early on that Big Ammo's JHP self-defense ammos --- typically rated 1350-1400 fps --- is more accurate than any JHP shot through my two 9mm pistols. By staying close to the caliber's design for effectiveness I'm not beating up the pistol as one does with +P/+P+ pressure 9mm ammo. After viewing dozens of YouTube gel tests and reading Big Ammo companies' test results I'm not on a quest for hyper velocity rounds that may provide minuscule measure of performance.

    I have no reason to compare 9mm with .35sig; they're two different calibers and both effective. But in my individual case the better accuracy with .357sig is the determining factor, with the added power the icing on the cake. There really isn't a valid reason for hatin' on one caliber and worshiping the other. If I didn't recognize both calibers for what they do I would ditch one of them.
  23. Underwood might be toning there ammo down which is bs if they are why buy 20 round boxes when you can buy the Speer 50 round box and get same velocity now

    Sent from my iPhone using Glock Talk
  24. You want to talk about weird things, I bought some Doubletap 9mm ammo just cause, and it was on sale at one helluva deal and so far it has actually been within 17 fps of advertised Velocity!

    What is going on in this Country!?!?! :faint:
  25. What he said
  26. You guys are killing me with thinking the temperature made a difference. It hardly has any effect on a pistol round 10 feet from a chrono. It was 45F when I did my test. That's not going to drop 100fps. 45F is not even that cold. I will chrono the load in warm weather for a comparison later. But for now I do have chrono data for Underwood's +P+ 9mm rated at 1300fps at hot and cold temps:

    38F, 1306 average velocity
    85F, 1311 average velocity

    I don't see a 100fps drop there. I think I just got a bad batch or they did lower their load a bit.

  27. The 357 Sig like other relatively high velocity calibers require longer barrels to reach their full potential. The UA 357 Sig from a 4 inch barrel is going to get 1500 fps, dropping down to a 3.4 inch barrel it will lose about 60 fps in velocity getting something in the 1440 fps neighborhood. This means you have only a 40 fps gap which could be caused by any one or combination of factors. Underwood stating that they use a 4.6 inch barrel is "questionable".

    I have never seen an ammo test where the UA 125gr 357 Sig out of a 4 inch barrel didn't get at least 1500 fps velocity. Here is the velocity out of a 4.6 inch barrel.

    This young man using the UA 125gr 357 Sig FMJ round was able to get 1620 fps velocity out of a 5 inch barrel and this test was done only last year.

    But if it's velocity you want note that he gets a 2200 fps velocity with the 65gr XD round. I would guess a velocity of 2000 fps could be had from a G33!

    View: https://youtu.be/rFepaP_dFG4
  28. This is easy...take the Glock barrel and test it against the KKM barrel.

    You'll have your answer. In general traditional ballard rifling (lands and grooves--which is what KKM uses) is slower than poly rifling found in a Glock barrel.

    Lastly, anyone who discounts the value of more velocity (or bigger bullets for that matter) has no perspective on practical ballistics...it all twisted internet armchair commando bullcrap. There's not a hunter on the face of the earth that would argue that a .300 Remington Ultra Mag is a less effective round than a .300 Blackout. Yet they both can use a 200 grain bullet at vastly different velocities. You can argue the recoil is objectionable and hard to manage but that's an objective observation and there are most certainly people who manage it nicely.
  29. Yup, cant compare RIFLE ballistics or Big Bore Revolver round ballistics to PISTOL Ballistics. No armchair needed, it's facts, not magic or Voodoo like some folks believe.. Cool thing about the 300 Black Out is it can be compared to a 45 AC0 sometimes with the 220gr Sub Scenic Loads. A 300 RUM it will never be.
  30. LOL, temp, sea level also affect results. How long have you been reloading?

    Have you competed in matches and chroned your loads in 25 degree weather and 85 degree weather. Results will vary.
  31. Yup, yup, I have had the ammo that was carried on my person, IWB have a lot more POP so to speak than the exact same ammo left in the cold, freezing Truck overnight.

    Now my ear and feel are not my Chronograph but there would more than likely been a difference in FPS.

    This is worth a curiosity test for myself. :cheers:
  32. Those that have competed in weather extremes requiring a measured power factor will attest to the variances in results.

    Ps sea level also a consideration.
  33. I used to do a bit of hunting with a Single Shot Rifle, and had the round in the chamber impact the target a little differently than the rounds I had stuck in my inside coat pocket next to my body. I would always check a cold shot for accuracy and note it and try to remember to carry my ammo in the side Saddle on the stock.
  34. Manufacturers use ideal conditions And sample many tests runs.
    They pick the most favorable results.
  35. Hi Rocky. I've been reloading since I was 17 years old, so 35 years now. I also compete a lot. I took 1st in the IDPA World Championship this year in my class/div. Also won 4 Glocks in GSSF, but I know they don't require PF mins. I'm well aware of the temperature issue, but honestly I don't see much variation. I use the same load year round, which is 130PF around 70F.

    I mentioned in the original post that I tested my "less than max" handloads along side the Underwood. My handloads were right at 1500, Underwood averaged 1405. So all else being equal - barrel rifling, temp, humidity, elevation, etc; the Underwood was 100fps slower than my handloads. My weak "starting" handload was at 1375fps.
  36. Not really true for Underwood. They are usually underated. Like others stated, we've never seen the 357sig run less than around 1500 in any test. That's why I did this post, I'm far below that.
  37. I apologize for the snide remark. Personally I have seen 110 fps growth on a 86 degree day.

    Underwood as well as others are humans selling a product. I’m more concerned with bullet setback and what the manufacturer will do if a gun gets blown up.
  38. I ordered a box of factory Federal HST and Speer Gold Dot and will test these side by side with the Underwood for comparison. If they all run 100fps or so low, then maybe it's the barrel or ambient conditions. If the factory loads are close to rated velocity, then somethings up with the Underwood loads I received. I'll post the results once I run the test. I'll also test the Glock OEM barrel.
  39. There's a YT vid where a guy tests the accuracy and velocity of different barrels (OEM and some aftermarket) and the OEM Glock barrels gave the highest velocities with each ammo he used. Just looking at polygonal compared to button makes me think there'd be more drag in the polygonal, thus creating more FPS.
  40. Aren't the 125 grain Gold Dots specifically designed for the 357 Sig and the velocities it generates?

    Speer is one of the reputable manufacturers that sells a lot of ammo to law enforcement and has a good reputation both in tests and actual results.

    Luckygunner tested 9mm 124 grain Gold Dots out of a Ruger PC carbine and the extra velocity caused under-penetration just as you predicted. Speer knew their 124 grain bullets could not handle 357 Sig velocity and that is why they make the 125 grain projectile.
  41. What powder do you use in the .357 sig, is it a compressed load. ?

    Myself not a fan of the Boutique manufacturers although Federal HST does reside sometimes in the household.

    Ive gifted my .357 sigs to my sons as Ive lost interest in the .357 sig.
  42. the reason polygonal barrels are more efficient is because they create a better seal between barrel and projectile. the rounded edges of the rifling provides a better seal than getting the projectile to deform to match square cut grooves.
  43. Underwood XTP +P 380acp is in my Beretta 84F's magazine, but I haven't ordered from them since they changed to 20rd boxes. That really peeved me
  44. OK...you wanna play stupid games... Who would argue the .475 Linebaugh is less effective than a 9mm? Or a .44 Mag, or a 454 Casull…. C'mon. Energy (provided by velocity) and size matter regardless of whether you discuss pistol or rifle ammo. If it didn't the .38 Special would widely be regarded as good as the .357 magnum...but only an idiot would make such a claim.
  45. nope, try again. It has to do with friction.
  46. I agree with both....the OEM rifling does create a better seal but at that expense comes more friction. Higher friction will 'bout 99.9% of the time yield higher velocities. There's no doubt the polygonal is accurate as my avatar is with a Gen 4 OEM G34 and it wasn't done with a Ransom.
  47. Well I was gonna play your stupid game then I realized if you get into a argument with some idiot on the internet, they will drag you down to their level and beat you with experience.

    Have a good day.
  48. Either Ammo is overstated or test by a individual is fault.
    No mystery here.
  49. I'm using Longshot. Loads are not compressed. I'm loading a 125gr ACME Bullet RN. Loading long at 1.155" due to the RN and needing to hit the sidewall with a 0.379" crimp. Plenty of room for the powder. I've also used their 122gr FP with similar velocities.
  50. Thanks for sharing.