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Posted: 9/1/2021 5:36:21 PM EDT
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repost with the broken picture links repaired Speer LE 75 Grain Gold Dot  Following in the footsteps of their successful 62/64 grain Gold Dot LE 223 Remington ammunition, Speer has introduced a 75 grain version of their blind-to-barriers “bonded” soft-point load (#24475).  This ammunition is loaded in nickel-plated brass with crimped and sealed primers, however, there is no sealant at the case mouth. The load is charged with “ball” powder. The head-stamp reads: “SPEER 15 223 REM”.    The form of the 75 grain Gold Dot is just what you would expect it to be, a longer and heavier version of the 62/64 grain Gold Dots.  Left to right: 1) 62 grain Fusion, 2) 62 grain Gold Dot, 3) 64 grain Gold Dot, 4) 75 grain Gold Dot. Accuracy I conducted an accuracy (technically, precision) evaluation of the Speer LE 75 grain Gold Dot ammunition following my usual protocol. This accuracy evaluation used statistically significant shot-group sizes and every single shot in a fired group was included in the measurements. There was absolutely no use of any group-reduction techniques (e.g. fliers, target movement, butterfly shots). The shooting set-up will be described in detail below. As many of the significant variables as was practicable were controlled for. Also, a control group was fired from the test-rifle used in the evaluation using match-grade, hand-loaded ammunition; in order to demonstrate the capability of the barrel. Pictures of shot-groups are posted for documentation. All shooting was conducted from a concrete bench-rest from a distance of 100 yards (confirmed with a laser rangefinder.) The barrel used in the evaluation was free-floated. The free-float handguards of the rifle rested in a Sinclair Windage Benchrest, while the stock of the rifle rested in a Protektor bunny-ear rear bag. Sighting was accomplished via a Leupold Competition Series 45x45mm scope adjusted to be parallax-free at 100 yards. A mirage shield was used. Wind conditions on the shooting range were continuously monitored using a Wind Probe. The set-up was very similar to that pictured below.  The Wind Probe.  The test vehicle for this accuracy evaluation was one of my semi-automatic precision AR-15s with a 24” Krieger barrel. The barrel has a 5.56mm Match chamber with a 1:7.7” twist. Prior to firing the 75 grain Gold Dot ammunition, I fired a 10-shot control group using match-grade hand-loads topped with the Sierra 55 grain BlitzKing. That group had an extreme spread of 0.62”.  Three 10-shot groups of the Speer LE 75 grain Gold Dot ammunition were fired in a row with the resulting extreme spreads: 1.12” 1.03” 1.05” for a 10-shot group average extreme spread of 1.07”. The three 10-shot groups were over-layed on each other using RSI Shooting Lab to form a 30-shot composite group. The mean radius for the 30-shot composite group was 0.32”. The smallest 10-shot group . . .  The 30-shot composite group . . .  Velocity I chronographed the Speer LE 75 grain Gold Dot ammunition from a semi-automatic AR-15 with a chrome-lined, NATO chambered, 20” Colt M16A2 barrel.  Chronographing was conducted using an Oehler 35-P chronograph with “proof screen” technology. The Oehler 35P chronograph is actually two chronographs in one package that takes two separate chronograph readings for each shot and then has its onboard computer analyze the data to determine if there is any statistically significant difference between the two readings. If there is a difference, the chronograph “flags” the shot to let you know that the data is invalid. There was no invalid data flagged during this testing. The velocity stated below is the muzzle velocity as calculated from the instrumental velocity using Oehler’s Ballistic Explorer software program. The string of fire consisted of 10 rounds over the chronograph.   Each round was single-loaded and cycled into the chamber from a magazine fitted with a single-load follower. The bolt locked-back after each shot allowing the chamber to cool in between each shot. This technique was used to mitigate the possible influence of “chamber-soak” on velocity data. Each new shot was fired in a consistent manner after hitting the bolt release. Atmospheric conditions were monitored and recorded using a Kestrel 4000 Pocket Weather Tracker.  Atmospheric conditions Temperature: 75 degrees F Humidity: 33% Barometric pressure: 30.05 inches of Hg Elevation: 950 feet above sea level The muzzle velocity for the 10-shot string of the Speer LE 75 grain Gold Dot ammunition fired from the 20” Colt barrel was 2652 FPS with a standard deviation of 11 FPS and a coefficient of variation of 0.42%. For comparison, here's some additional chronograph data; this time from a Noveske 14.5" N4 barrel.   .... |
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Quoted: @molon Thank you for all your contributions. Will these stabilize in a 1:9 twist from a 16” or 20” barrel? The 75 grain Gold Dot is one of the shortest of the "heavy" .224 caliber bullets. As such, it does not require as fast of a twist as the longer projectiles do. According to Ballistic Performance Of Rifle Bullets, "the recommended twist for optimal performance is 1:9.4" or faster."  ... |
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I doubt that there are any significant changes, but does anybody know if the the older box/product number stuff (24475) differs any from the newer box/product number (24469)? Other than just the packaging? BTW, most of my 'older' [look] box stuff is immaculate, and new purchases even include a blue primer sealant, which I'm not sure was on the bullets I've shot or stacked over the past 8 years or so.. |
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Quoted: The 75 grain Gold Dot is one of the shortest of the "heavy" .224 caliber bullets. As such, it does not require as fast of a twist as the longer projectiles do. According to Ballistic Performance Of Rifle Bullets, "the recommended twist for optimal performance is 1:9.4" or faster." https://www.ar15.com/media/mediaFiles/28568/224_heavy_bullet_comparisons__01b-2081946.jpg ... Great data as always. |
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Quoted: False. ... Quoted: Quoted: My reading leads me to believe they are more of an SBR round. False. ... There was some testing done awhile back (from eagle19 or something or other?) that showed, IIRC, that this round gained most of its velocity in the SBR lengths, and tapered off quickly towards the teens. More so than other rounds I mean. But that’s offhand and it’s been a minute. I do feel the round shines as an SBR round, but obviously it still works from and benefits from a longer barrel. |
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Quoted: There was some testing done awhile back (from eagle19 or something or other?) that showed, IIRC, that this round gained most of its velocity in the SBR lengths, and tapered off quickly towards the teens. More so than other rounds I mean. But that’s offhand and it’s been a minute. I do feel the round shines as an SBR round, but obviously it still works from and benefits from a longer barrel. This load shoots superbly from 20" barrels and it's terminal ballistics are text-book perfect from 20" barrels. ... |
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Quoted: This load shoots superbly from 20" barrels and it's terminal ballistics are text-book perfect from 20" barrels. ... Quoted: Quoted: There was some testing done awhile back (from eagle19 or something or other?) that showed, IIRC, that this round gained most of its velocity in the SBR lengths, and tapered off quickly towards the teens. More so than other rounds I mean. But that’s offhand and it’s been a minute. I do feel the round shines as an SBR round, but obviously it still works from and benefits from a longer barrel. This load shoots superbly from 20" barrels and it's terminal ballistics are text-book perfect from 20" barrels. ... I don’t doubt that, it’s a great round all around. The last time we did this it had something to do with conjecture that they used faster burning propellant to get most of the velocity gain out early on in the barrel length. Obviously it still benefits from added length, it’s just already gotten most (more than usual) of its velocity early on, such that you lose less performance with this round vs competitors when shot from an SBR. I sort of standardized on the 55 GD, but I’ve got plenty of 75’s and they’re a very nice loading. I’ve used both on game and they perform as advertised. |
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Quoted: The last time we did this it had something to do with conjecture that they used faster burning propellant to get most of the velocity gain out early on in the barrel length. I deal in facts, not conjecture and the fact of the matter is that the 75 grain Gold Dot has better terminal ballistics when fired from a 20” barrel than when fired from SBRs. Thus, the statement “they are more of an SBR round” is categorically false. ... |
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Quoted: I deal in facts, not conjecture and the fact of the matter is that the 75 grain Gold Dot has better terminal ballistics when fired from a 20” barrel than when fired from SBRs. Thus, the statement “they are more of an SBR round” is categorically false. … Quoted: Quoted: The last time we did this it had something to do with conjecture that they used faster burning propellant to get most of the velocity gain out early on in the barrel length. I deal in facts, not conjecture and the fact of the matter is that the 75 grain Gold Dot has better terminal ballistics when fired from a 20” barrel than when fired from SBRs. Thus, the statement “they are more of an SBR round” is categorically false. … The conjecture was from how the results came out how they did, not what the results were. I think we are talking past each other. Of course the round performs better from a longer barrel. Most every round does unless comparing extremes in both ammunition and barrel lengths. We don’t disagree. What was being said was that the loading shines as an SBR round because it gains more velocity early on than other comparable loadings. To put this another way, someone selecting ammunition for an SBR would do well to choose this ammunition over similar competitive offerings due to that higher initial velocity gain. Not that someone should shoot this from an SBR as opposed to a 20” because it’ll work better. I can’t speak for the other poster, but I don’t think he meant that, and I definitely didn’t mean that. If you think that, you’re tilting at windmills because that’s a strawman I won’t defend. You’re an intelligent poster so I’m not sure if you’re intentionally being obtuse about this. If this is something you just have to be right about because of semantics then have at it, but I’ve clarified my point more than enough that all but the most extreme autists can understand. Because we are in tech, I’m leaving it at that. Edit: and I don’t want to be a jerk. There’s an equally good chance I just didn’t articulate my point well enough. I’ve done it before. I’ll do it again. If that’s the case I apologize. |
| Well thanks gents. Didn’t meant to start an argument I was honestly curious because even Speer states that this round is for barrel lengths under 16” and most post regarding it all always mentioning it as an SBR round so I was thinking it was loaded for shorter tubes so I wasn’t sure if a longer tube would decrease it’s terminal performance kinda like how the TMK out of a 20 inch was lacking penetration. Apologies for wording my question incorrectly. Good to know 75gr gold dot preforms regardless of barrel length. |
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Quoted: Well thanks gents. Didn’t meant to start an argument I was honestly curious because even Speer states that this round is for barrel lengths under 16” and most post regarding it all always mentioning it as an SBR round so I was thinking it was loaded for shorter tubes so I wasn’t sure if a longer tube would decrease it’s terminal performance kinda like how the TMK out of a 20 inch was lacking penetration. Apologies for wording my question incorrectly. Good to know 75gr gold dot preforms regardless of barrel length. Ah then yes definitely it’s fine from longer barrel lengths. Sorry if I misunderstood your intent. Rounds that rely more on fragmentation can be prone to having a “sweet spot” of velocity for optimal performance. Too slow and it doesn’t frag but too fast and it frags too destructively and penetrates shallow. The TMK or VMAX are examples. With the GD and Fusion this is a whole lot less of a thing. I’d want it going as fast as possible (within reason), all you’re doing is ensuring optimal expansion and increasing your effective range. I wouldn’t be concerned about using longer barrel lengths and, all things else equal, I’d prefer it. Anecdotally I can only speak to 55 GD from 10.3-18” and 75 GD from 14”. They’ve always performed consistently well terminally on whitetails from 25-150m, and I’d trust it in an HD capacity based on what I saw from some pretty thrashed chest cavities. |
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Quoted: Good to know 75gr gold dot preforms regardless of barrel length. Be aware that the claims about the 75 grain Dold Dot load having a significantly higher velocity than other 75 grain loads when fired from SBRs is mostly BS also. When fired from 14.5” SBRs the 75 grain Gold Dot load is only 3 FPS faster than 75 grain 5.56 TAP SBR, 13 FPS faster than 75 grain 223 TAP and it’s 164 - 186 FPS slower than 75 grain 5.56 TAP T2.   …. |
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Quoted: @Molon have you done 75gr TAP SBR? I can't remember/find it. https://www.ar15.com/forums/topic.html?b=3&f=16&t=695432&tl=-ARCHIVED-THREAD-Range-Report-Hornady-5-56mm-75-Grain-TAP-SBR ... |
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The 75gr GDSP was designed to “work” through a very wide barrel length operating range, meaning that it can perform to FBI BRF protocol standards out of a much wider range of barrel lengths than many other rounds. This is because it can expand and still sufficiently penetrate through barriers at a wider velocity envelope. Vista Outdoor (parent company of Federal/Speer) specifically designed this round to function (expand and penetrate) at 100yds or longer out of barrels down to 7” in length. The powder they use allows it to gain sufficient velocity out of SBRs to perform to needed protocol standards. This 75gr is not specifically designed as an SBR round, but was designed to be the ideal round for SBRs as opposed to anything else being offered. It gives ideal performance at the most common LE SBR length, 11.5”, as well as the most typical non-SBR length of 16”. The 75gr was designed to alleviate the issue of other rounds having a much more narrow velocity operating window. Glad to see some good numbers. Early testing of the 75gr accuracy was not as promising but Vista has since resolved that issue. That accuracy issue was what initially delayed my agency adopting the 75gr over the 62gr Federal TBBC until Vista resolved it. We were slated to be one of the first agencies to adopt it but had to delay out of concerns for the accuracy. We have since adopted it now and seen very satisfactory performance. |
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My Dept has used Fed Tactical 55gr (TBBC) for years but just prior to Covid we re-evaluated our ammo. This was done during some testing to switch from 147gr HST to 124gr +P HST I participated in the FBI protocol testing for handgun, rifle and shotgun ammo. We found the Gold Dot 75gr performed the best especially out of guns under 16” You can’t go wrong with Fed Tac or Gold Dot across the board. Another advantage was that Gold Dot was cheaper which plays a role when purchasing a million rounds a year of various calibers. |
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Quoted: My Dept has used Fed Tactical 55gr (TBBC) for years but just prior to Covid we re-evaluated our ammo. This was done during some testing to switch from 147gr HST to 124gr +P HST I participated in the FBI protocol testing for handgun, rifle and shotgun ammo. We found the Gold Dot 75gr performed the best especially out of guns under 16” You can’t go wrong with Fed Tac or Gold Dot across the board. Another advantage was that Gold Dot was cheaper which plays a role when purchasing a million rounds a year of various calibers. Very good info. Thanks. Do you remember what the 75GD was better at? Retained weight? Specific barrier penetration? Or just better at everything? |
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It was better at meeting desired depth and expansion for 10.5 to 16” barrels It performed better after passing through intermediate barriers (windshield, car door, clothing) I still think the Fed Tac 55 & 62gr ammo are excellent performers but the 75gr Gold Dot shines in SBRs |
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Quoted: My Dept has used Fed Tactical 55gr (TBBC) for years but just prior to Covid we re-evaluated our ammo. This was done during some testing to switch from 147gr HST to 124gr +P HST I participated in the FBI protocol testing for handgun, rifle and shotgun ammo. We found the Gold Dot 75gr performed the best especially out of guns under 16” You can’t go wrong with Fed Tac or Gold Dot across the board. Another advantage was that Gold Dot was cheaper which plays a role when purchasing a million rounds a year of various calibers. How did the 124 +p HST compare to 147gr HST? I carry the 124 +p version. |
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Quoted: How did the 124 +p HST compare to 147gr HST? I carry the 124 +p version. Performance from 3 inch barrel HST 124gr +P  Ammo Quest 9mm: Federal HST 124+P ammo test P9HST3 in ballistic gel Performance from 3 inch barrel HST 147gr  Ammo Quest 9mm: Federal HST 147gr standard pressure test in ballistic gel How these tests differ from a duty size gun (4+ inch barrel) in direct comparison is not really well known. Most tests I have seen from duty size pistols show that both these rounds are excellent performers. |
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Quoted: How these tests differ from a duty size gun (4+ inch barrel) in direct comparison is not really well known. Yes, it is. Federal 9mm Luger 147 Grain HST  Federal’s Premium Law Enforcement Ammunition line-up currently includes four different 9mm Luger loads that utilize 0.355” versions of their hollow-point HST bullet. As the title of this article states, the standard pressure 147grain load (P9HST2) will be the focus of this article. All versions of the 9mm Luger HST ammunition are loaded in nickel-plated, brass cases. The case-head for the P9HST2 is stamped “F C 9MM LUGER”. This version is loaded to a cartridge nominal OAL of 1.125”. The primers are sealed, but are not crimped in place. The case mouths are also sealed. The round is charged with a “flake” powder.   The individual squares in the red grid below measure one-tenth of an inch.  The 147 grain HST projectile has a nominal length of 0.680”. The bullet has a deep cannelure and six skives in the copper jakcet. The skives on the 9mm HST projectiles are the longest of any of the 9mm Luger law enforcement loads that I’ve evaluated to date.  The 9mm HST projectiles have a very unique construction, in that the lead-core directly beneath the skives has a crown-shaped cut-out.  Federal’s literature claims that the 9mm Luger 147 grain HST load has a muzzle velocity of 1000 FPS. When chronographed from my Gen 2 Glock 19 (with the factory original barrel) over an Oehler 35P chronograph, the P9HST2 load had a muzzle velocity of 1018 FPS with a standard deviation of 11 FPS! Dr. GK Roberts has stated that the 9mm 147 grain HST rounds “are among the finest 9 mm duty loads currently available.” Terminal ballistic testing in 10% ordnance gelatin conducted by the good doctor produced the following results . . .   I evaluated the accuracy of the P9HST2 load from a distance of 25 yards using two different platforms; my Gen 2 Glock 19 and a Colt 6450 with a free-floated Noveske barrel.  When using hand-loads topped with the Hornady 125 grain HAP bullet, my Noveske barreled Colt 6450 has turned in 10-shot groups at 25 yards that have extreme spreads of less than a half-inch.  A 10-shot group of the P9HST2 ammunition fired from the Noveske barreled 6450 at 25 yards had an extreme spread of 0.83”.  Firing from the bench at a distance of 25 yards, my Gen 2 Glock 19 (with the factory original barrel) produced a 10-shot group with an extreme spread of 2.05”.  …. Federal 9mm Luger (+P) 124 grain HST  Federal’s Premium Law Enforcement Ammunition line-up currently includes four different 9mm Luger loads that utilize 0.355” versions of their hollow-point HST bullet. As the title states, the plus-P, 124 grain load (P9HST3) will be the focus of this article. All versions of the 9mm Luger HST ammunition are loaded in nickel-plated, brass cases. The case-head for the P9HST3 is stamped “F C 9MM + P”. This version is loaded to a cartridge nominal OAL of 1.100”. The primers are sealed, but are not crimped in place. The case mouths are also sealed. The round is charged with a “flake” powder.   (The individual squares in the red grid below measure one-tenth of an inch.)  The 124 grain HST projectile has a nominal length of 0.595”. The bullet has a deep cannelure and six skives in the copper jakcet. The skives on the 9mm HST projectiles are the longest of any of the 9mm Luger law enforcement loads that I’ve evaluated to date.  The 9mm HST projectiles have a very unique construction, in that the lead-core directly beneath the skives has a crown-shaped cut-out. Federal’s literature claims that the 9mm Luger (+P) 124 grain HST load has a muzzle velocity of 1200 FPS. When chronographed from my Gen 2 Glock 19 (with the factory original barrel) over an Oehler 35P chronograph, the P9HST3 load had a muzzle velocity of 1215 FPS with a standard deviation of 11 FPS! Dr. GK Roberts has stated that the 9mm (+P) 124 grain HST rounds “are among the finest 9 mm duty loads currently available.” Terminal ballistic testing in 10% ordnance gelatin conducted by the good doctor produced the following results . . .   I evaluated the accuracy of the P9HST3 load from a distance of 25 yards using two different platforms; my Gen 2 Glock 19 and a Colt 6450 with a free-floated Noveske barrel. When using hand-loads topped with the Hornady 125 grain HAP bullet, my Noveske barreled Colt 6450 has turned in 10-shot groups at 25 yards that have extreme spreads of less than a half-inch. A 10-shot group of the P9HST3 ammunition fired from the Noveske barreled 6450 at 25 yards had an extreme spread of 0.98”.  Firing from the bench at a distance of 25 yards, my Gen 2 Glock 19 (with the factory original barrel) produced a 10-shot group with an extreme spread of 2.29”.  ….. |
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