SubSonic Loads for .223
While I have never loaded subsonic loads for the AR...I have loaded some reduced loads for a .223 Bolt Gun that I used for a long range squirrel rig.
I used both .22 Hornet and .221 Remington Fireball data from P.O. Ackleys Handbook for Shooters and Reloaders as a starting point and obtained good results as a result.
Using a Lake City Casing, a Rem 7 1/2 SRBR Primer 11.0 Gr of Hogdon H110 behind a Sierra 50 Grain Softpoint I obtained very good accuracy in my 700BDL Varminter and even found this load to shoot to the same Point of Impact out to 100 yards as my full power Varmint load.
Ackleys book list .221 Rem Fireball Data for bullets up to 70 grains...He recommends 14.5 Grains of IMR 4227 behind a 70 grain soft point to obtain 2340 FPS.
I personally shot the H110 load alot and even tried it with and without the old Cornmeal filler trick with identical results.
Good Luck and I hope this helps out.
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