Range Report - 90gr TNT and Benchmark chrono info

[CAM_PIN]

Been a long time lurker, and would like to share the following range results since I haven't found much info on this combo. Hope it can help someone. As usual, consider this info as dangerous. You need to do a proper reloading workup to find out what is safe in your rifle.

This was mostly an exercise in getting a firing on some new brass, but I thought that the data could be helpful. I've never shot this combo before, and was mostly concerned with getting some velocities and finding a max load. All 50 rounds were shot at the same POA at 200 yards. FWIW, all charge weights combined went about 3 MOA. This rifle shoots sub MOA all day long with 120gr Gold Dots for comparison.

18" Odin Works 1:8 barrel and BCG (intermediate gas length)
Sandman-S suppressor
Primary Arms SLx 5x36mm scope
Magnetospeed V3 chrono

Temp: 75
Wind 10mph gusty from 9:00
DA: 2100'

Benchmark powder
Speer 90gr TNT bullets
CCI #41 primers
Hornady brass - unfired
COAL: 2.20'

Using Speer's data, 5 rounds each from 28.5-31.2 grains of Benchmark, in 0.3gr increments.

Code:

[B]28.5gr[/B] - 36.9 SD - 2597 fps avg [B]28.8gr[/B] - 39.2 SD - 2610 fps avg [B]29.1gr[/B] - 22.8 SD - 2674 fps avg [B]29.4gr[/B] - 34.0 SD - 2664 fps avg [B]29.7gr[/B] - 8.4 SD - 2707 fps avg [B]30.0gr[/B] - 11.5 SD - 2756 fps avg [B]30.3gr[/B] - 15.0 SD - 2774 fps avg [B]30.6gr[/B] - 14.5 SD - 2786 fps avg [B]30.9gr[/B] - 11.0 SD - 2815 fps avg (max in this rifle) [B]31.2gr[/B] - 14.5 SD - 2865 fps avg (shows primer flattening)

The 31.2 grain charge weight started to show some primer flattening. Since the Grendel max pressure is only 52000 psi, I am gonna back off and call 30.9 grains as max in this rifle.

In the charge weight vs. velocity plot, 29.4 grains and 30.3 grains showed a flat spot in the curve - probably gonna do some investigation around the 30.3 charge weight.

[BluntForceTrauma]

Thanks for the data!

[northdude]

Try some 748. Ive had good success with that using 85gr sierra hp. Getting 3000fps and under 1/2" at 100m

[sundowner]

Try H335 have sub moa using 31.5gr , with 2980fps .

[Smtimelevi]

Thanks for posting, I have the same barrel and was thinking of trying these projectiles

[Javman]

Been a long time lurker, and would like to share the following range results since I haven't found much info on this combo. Hope it can help someone. As usual, consider this info as dangerous. You need to do a proper reloading workup to find out what is safe in your rifle.

This was mostly an exercise in getting a firing on some new brass, but I thought that the data could be helpful. I've never shot this combo before, and was mostly concerned with getting some velocities and finding a max load. All 50 rounds were shot at the same POA at 200 yards. FWIW, all charge weights combined went about 3 MOA. This rifle shoots sub MOA all day long with 120gr Gold Dots for comparison.

18" Odin Works 1:8 barrel and BCG (intermediate gas length)
Sandman-S suppressor
Primary Arms SLx 5x36mm scope
Magnetospeed V3 chrono

Temp: 75
Wind 10mph gusty from 9:00
DA: 2100'

Benchmark powder
Speer 90gr TNT bullets
CCI #41 primers
Hornady brass - unfired
COAL: 2.20'

Using Speer's data, 5 rounds each from 28.5-31.2 grains of Benchmark, in 0.3gr increments.

Code:

[B]28.5gr[/B] - 36.9 SD - 2597 fps avg [B]28.8gr[/B] - 39.2 SD - 2610 fps avg [B]29.1gr[/B] - 22.8 SD - 2674 fps avg [B]29.4gr[/B] - 34.0 SD - 2664 fps avg [B]29.7gr[/B] - 8.4 SD - 2707 fps avg [B]30.0gr[/B] - 11.5 SD - 2756 fps avg [B]30.3gr[/B] - 15.0 SD - 2774 fps avg [B]30.6gr[/B] - 14.5 SD - 2786 fps avg [B]30.9gr[/B] - 11.0 SD - 2815 fps avg (max in this rifle) [B]31.2gr[/B] - 14.5 SD - 2865 fps avg (shows primer flattening)

The 31.2 grain charge weight started to show some primer flattening. Since the Grendel max pressure is only 52000 psi, I am gonna back off and call 30.9 grains as max in this rifle.

In the charge weight vs. velocity plot, 29.4 grains and 30.3 grains showed a flat spot in the curve - probably gonna do some investigation around the 30.3 charge weight.

With the factory Federal stuff I got 2955fps but used a 22" WC SS.

[LRRPF52]

+1 for H335 being great under the 90gr TNT

With factory Federal loaded 90gr TNT ammo, I’m getting about 2700fps from 12” suppressed with .30 cal TBAC Ultra 5.

[Happy2Shoot]

18" Odin Works 1:8 barrel and BCG (intermediate gas length)
Sandman-S suppressor

@CAM_PIN

Please take a moment and tell me about your Sandman-S.

I have one in jail, and the wait is killing me.

All I have are other peoples stories to keep me occupied.

I have an 18" and a 12.5" Grendel.