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Posted: 1/25/2022 9:40:38 PM EDT
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reposted by request Black Hills 223 Remington 75 Grain Match HP Ammunition Blue Box versus Red Box  The difference between Black Hills’ red box and blue box ammunition lies primarily with the brass case. Red box ammunition is newly manufactured using virgin brass. Blue box ammunition is referred to as “remanufactured” because is uses once fired brass that has been resized. This enables Black Hills to sell the blue box ammunition at a reduced price compared to their red box ammunition. Black Hills’ 75 grain Match HP (hollow point) ammunition is loaded with Hornady’s 75 grain BTHP Match bullet with a cannelure (commonly referred to as the “T1C”) and both the red box and blue box loads have a crimp at the case mouth. Both loads are charged with “ball powder.” The nominal OAL for the red box cartridges ran approximately 2.245” and for the blue box cartridges it was closer to 2.250”.  The brass cases used in the red box ammo have sealed primers and the headstamp of most lots of this load read “BHA 223 MATCH.” These virgin cases have a nominal length of 1.755”. The brass cases used in the blue box load tend to be a mix of once fired Lake City and Winchester brass. The military primer crimps has been removed by the reaming method. The blue box loads do not have sealed primers. Black Hills does not perform a “trim to length” operation on the resized cases used in the blue box ammunition. As a result, many of the cases are longer than the SAAMI recommended maximum length of 1.760”. Several of the cases that I measured had a length of 1.775”. This could potentially cause problems in a barrel with a minimum length chamber, though no malfunctions of any kind were experienced during the testing of this ammunition. (Using a Sinclair chamber length gauge, I determined the chambers of my Colt barrels have a length of 1.780”.) Both loads were chronographed using four different length barrels. All of the Colt barrels used in testing have a NATO chamber and a 1:7” twist. The 24” Krieger barrel has a 5.56 Match chamber and has a twist rate of 1:7.7”. On their web-site, Black Hills advertises a muzzle velocity of 2,750 fps for these loads, but they do not state the barrel length associated with this velocity, though the industry standard calls for a 24” 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 statistically significant difference in the readings, 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 Average temperature- 80 degrees F Humidity - 48% Barometric pressure – 29.04 Elevation- 960 feet above sea level  While chronographing the Black Hills loads through the 24” Krieger barrel, I also chronographed three of Hornady’s SAAMI pressure, 75 grain loads that use the T1C bullet for comparison.  For additional comparison, I also fired the Black Hills loads side-by-side with some of the Hornady 75 grain SAAMI pressure loads from the 20” Colt A2 barrel.  100 yard Accuracy Evaluation of Black Hills 75 grain MHP Red Box versus Blue Box As previously discussed in this thread, the primary difference between Black Hills' red box and blue box ammunition lies with the brass case. Red box ammunition uses virgin brass, while blue box ammunition uses once fired brass that has been resized. The test-vehicle for this accuracy evaluation was a semi-automatic AR-15 with a 24” stainless-steel Kreiger VarMatch barrel, with a 1:7.7” twist, installed on a LaRue Tactical Stealth upper receiver. I conducted an accuracy (technically, precision) evaluation of the Black Hills 75 grain Match HP 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. 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 Scope which was 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. Control Groups Prior to testing the Black Hills ammunition, I obtained three 10-shot groups of a control load consisting of hand-loaded Sierra 55 grain BlitzKings (at a distance of 100 yards of course.) Those three groups had extreme spreads of: 0.547” 0.57” 0.69” for an average extreme spread of 0.602”. The three 10-shot groups were overlayed on each using RSI Shooting Lab to obtain a 30-shot composite group that had a mean radius of 0.19”. Red Box Following the same procedures used with the control load, three 10-shot groups of the Black Hills red box 75 grain MHP fired from 100 yards were obtained. Their extreme spreads measured: 0.96” 1.00” 1.04” for an average extreme spread of 1.00”. As with the control load, the three 10-shot groups from the red box ammunition were over-layed on each other to obtain a 30-shot composite group with a mean radius of 0.32”. Blue Box In the same manner as above, three 10-shot groups of the blue box 75 grain MHP were obtained from 100 yards with extreme spreads of: 1.11” 1.16” 1.16” for an average extreme spread of 1.14”. Those three 10-shot groups overlayed on each other had a mean radius of 0.37”. Here are the 30-shot composite groups side-by-side for comparison.  Lastly, for any Internet Commandos in our viewing audience, I fired a 3-shot group of the red box 75 grain MHP from 100 yards. That group measured 0.276”.    ..... |
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When I first started highpower rifle competition through my first Camp Perry summer I began with a 500-round case of Black Hills Blue Box 75s. Every round went exactly where I pointed it, and was good for another loading of Hornady 75s I bought on Commercial Row at the National Matches for the next year. Decent ammo at a fair price, though I don't know what China flu has done to pricing. |
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About 10 years ago I weighed the ball powder from Black Hills blue box 77 SMK. Pretty sure Black Hills no longer sells any Blue Box remanufactured ammo. But anyhow, the powder weighed 23.9 grains, and appearance was identical to TAC. I assembled a copycat load from my own components of TAC and 77 SMKS. Fired my handloads and the Blue Box stuff over the chronograph. Velocity of both were low 2700’s from 20” barrel. Curious what powder Black Hills is using these days. |
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Quoted: About 10 years ago I weighed the ball powder from Black Hills blue box 77 SMK. Pretty sure Black Hills no longer sells any Blue Box remanufactured ammo. But anyhow, the powder weighed 23.9 grains, and appearance was identical to TAC. I assembled a copycat load from my own components of TAC and 77 SMKS. Fired my handloads and the Blue Box stuff over the chronograph. Velocity of both were low 2700’s from 20” barrel. Curious what powder Black Hills is using these days. Of all the loads I've done from 73 ELD's, 75 OTM Type 1's, Berger 77 OTM, and 77 SMK or TMK's, the magic number has always been the exact same with 23 grains of Tac, FGMM 205MAR, and using various lots of LC seated at what either Hornady or Sierra suggests. I should chronograph some from my 16" Criterion Hybrid one day. |
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Groups were excellent. I used that ammunition to train and compete in National Match highpower rifle events. Any shot that didn’t land in the ten-ring at 200/300/600 yards was completely my fault in poor execution. I earned my final leg for the Distinguished Rifleman award shooting those Blue Box 77’s on the Viale range at Camp Perry in 2014. 2014 was an unusual year, in that the Awards Ceremony was on the same day as the National Trophy Individual Match. I finished at the 600-yard-line with a score good enough for Silver Medal (top 5% of non-distinguished shooters) in the mid-afternoon. Awards ceremony, and pinned Distinguished a couple hours later. Hey, it only took me 20 years to get there! So yeah, you could say I have a little nostalgia for Black Hills Blue Box. The others in the pic are the 2014 "graduating class" of those who earned the Distinguished Rifleman award in 2014. Attached File Attached File Attached File |
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Y'all motivated me to dig up some of my notes on the Blue Box. I ran some numbers through Quickload to see what would be the necessary powder charge to duplicate the 77SMK Blue Box ammo. I ran these Quickload numbers, and created the chart all those many years ago, using 28.5 grains H20 case-capacity (which is the default number for the Quickload program). Quickload's 28.5 number is wrong. Actual case capacity of most 223/5.56 cases is 30.2 grains H20. So, to the extent you may wish to use this chart as a reference, be advised that those same numbers run with 30.2 grains H20 capacity, will REDUCE ACTUAL VELOCITY by about 100 fps for each load. Attached File |
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And for some reason I saved this target pic. Rifle was a Colt 6940 with a Leupold 3-9 slapped on it. Laid over an ammo can and fired at 200 yards. Not exactly "Molon" level testing. But I'd say the ammo performed for the conditions. Attached File |
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And here are some chronograph numbers I got when I was testing with TAC and 77SMK's to try to duplicate the Black Hills numbers Attached File |
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And some more chronograph numbers from 2010 This was Black Hills Blue Box 77SMK. Same stuff I took with me to Camp Perry in 2014 to finish the Distinguished Rifleman thing. This is the Black Hills blue box ammo that had 23.9 grains of "ball powder" (which I am confident was TAC). chronograph numbers. Ten shots. 2692 2720 2701 2709 2710 2697 2728 2687 2698 2680 14.7 standard deviation 2702.2 Average FPS 20” barrel Note that 14 fps deviation in velocity will give you about two inches variation in elevation impact at 600 yards. 100 fps difference at 600 yards will be about TEN INCHES variation up-and-down. Attached File |
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