Blue Dot, 9mm 124 FMJ. Velocity question.

I am trying to develop a load for Blue Dot using Everglades Ammo 124 FMJ and CCI 500 primers.

The book load calls for a max of 7.9 grains using a Speer 124 GDHP, Hornady's "What if my bullet is not a match for the listed bullet" implies (in my reading) that a round nose FMJ can be substituted for a HP bullet.

I loaded several steps leading up to a maximum of 7.8 Grains, mixed p/u brass, 1.12 OAL as specified by Alliant. The velocity I got out of an 8" PSA PA-9 was very stout! All 6 of the loads averaged in the ballpark ([email protected] Grains to [email protected] Grains).

Let's take a look at the 7.5 grain load specifically since it's the only one I got a reference string using a shorter barreled Pistol (4.5" Springfield Armory XDm-9)

7.5 grains PA-9 8"
1488
1517
1509
1514
1517
Avg: 1509
Std: 12.19

Win NATO 124Gr, PA-9 8" (for reference)
1304
1319
1329
1341
1310
Avg: 1320.6
Std: 14.81


7.5 grains XDm 4.5"
1323
1321
1312
1364
1338
Avg: 1331.6
Std: 20.38

The brass was being flung pretty far as you can imagine. I've examined all the primers from the XDm and while a couple of the XDm primers are showing a little loss of edge roundness, the 2 dozen or so I have from the PSA (firing at an average of 1500 FPS!) look completely normal.

My essential question: This load has a listed velocity in a 4" barrel of 1238 using the 124 GDHP and 7.9 grains. I'm exceeding that by 100 fps in a pistol with a barrel 1/2" longer and almost 300 Fps in a pistol with a double length Barrel (8")

Does this constitute a situation that's "too good to be true" Are those velocities telling me that this load with this bullet is probably well into or beyond +p range for 9mm in your opinions? 600 Foot Pounds of muzzle energy from a 9mm, even with an 8" barrel, seems stout.

Accuracy was fine, rested off a pistol case with a towel over it. The groups below are from the PSA 8". I should add that I'm completely blown away by the quality of this weapon. It will put Win NATO 124 gr in basically 1 hole at about 40' and has been completely reliable while having a feel of quality and solidity that makes me think PSA has this thing dialed in!

Thanks so much for the replies. I’ll definitely bump up OAL to compensate for the diff, may back off some

derek45 said:

Here's what I got...

right at 1300 fps

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how close were you to your chrony ?
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Click to expand...

Great reference, thanks! I was about 7 or 8 feet from the Chrony, trying to keep it at the 5+ specified minimum distance.

I think with it's uniquely high volumes of powder Blue Dot really does outperform other choices for longer barrels, the FPS gain per inch of barrel length seems pretty atypical. I want to shoot for accuracy at 50 yards and get at least a few velocities from a 16" AR9 that these loads will also be used in. I'll add those velocities to this thread when I do.

I'm getting a sense that pressures are probably in or lower than 9MM +P but that this load will be significantly harder on guns than, say 4.5 grains of tite group, etc.

sparkyv said:

Ditto.

Click to expand...

I've only got 1 pound of it, sadly, but it's looking like my 1k of EA 124 FMJ's will be paired up with that and mostly take care of both quantities, or close.