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El Torote · October 10, 2012, 12:32 AM

For the .223, My book listed RL15 23.5 min.- 25.5 max at 3066 fps. Using a 24" 1:12 at 2.25 COAL

However online, the 5.56 load lists RL15 25.2 min. 27.2 max at 3019 fps using a 20" 1:7 at 2.24 COAL

http://www.barnesbullets.com/wp-cont.../5.56-Nato.pdf

I loaded RL15, and used a 5.56 nato 16" 1:7 at 2.26 COAL for the following results:

24.7 2775 fps
24.9 2800
25.1 2806
25.3 2825
25.5 2850
25.7 2886

I shot Silver Bear 62 HPBT to compare and chrono'd 2960 fps vs 3050 listed.

Since my first TTSX loads were about 180 fps off of the the book max vs the 90-100 fps I expected using the 16" barrel I will use the 5.56 data and finish laddering from 25.9 to 27.2 and chrono.

Only concern I have is that at 25.1 gr I was at 2806 vs. 2783 at 25.2 min in the book. Actually higher than the book's 20" bbl with my 16". Perhaps it was because I loaded 2.26 vs. 2.24 coal. Maybe more pressure. Oh well we shall see.

October 10, 2012, 12:32 AM	#14
El Torote Junior Member Join Date: February 22, 2010 Posts: 2	My results For the .223, My book listed RL15 23.5 min.- 25.5 max at 3066 fps. Using a 24" 1:12 at 2.25 COAL However online, the 5.56 load lists RL15 25.2 min. 27.2 max at 3019 fps using a 20" 1:7 at 2.24 COAL http://www.barnesbullets.com/wp-cont.../5.56-Nato.pdf I loaded RL15, and used a 5.56 nato 16" 1:7 at 2.26 COAL for the following results: 24.7 2775 fps 24.9 2800 25.1 2806 25.3 2825 25.5 2850 25.7 2886 I shot Silver Bear 62 HPBT to compare and chrono'd 2960 fps vs 3050 listed. Since my first TTSX loads were about 180 fps off of the the book max vs the 90-100 fps I expected using the 16" barrel I will use the 5.56 data and finish laddering from 25.9 to 27.2 and chrono. Only concern I have is that at 25.1 gr I was at 2806 vs. 2783 at 25.2 min in the book. Actually higher than the book's 20" bbl with my 16". Perhaps it was because I loaded 2.26 vs. 2.24 coal. Maybe more pressure. Oh well we shall see.