[Roseaukaine]

Figured I’d start a new post with my initial test data using the above powders.
This is a work in progress. Just sharing my experience. Opinions and suggestions welcome.


Rifle- TC Venture .270
CBB 120 MKZ
Powder 1 - staBall 6.5
Brass - Peterson New; Mandrel sized neck to .275 ID
primer - Federal 210M
starting COAL 3.140; OTB 2.674 ( .050 off lands )
Lee factory crimp die - light crimp.

starting charge at 52.0g working up to 53.4g
Optical Chronograph was acting up so not certain if I trust the data. Sunny skies; in direct sunlight.
52g - 2992fps
52.5- 3620fps
52.8g - 3052fps
53.1g- 3774
53.4g-3380
53.4g- 3473
No pressure signs on brass or primers. Bolt lift fine.
Shots 1,2,and 4 clover leafed. Shot 3 off to left 1”. Shots 5,6,7 all within 1/2” of each other.

Will load up 3 of each at 52.8, 53.0, and 53.2 and check for grouping.

Powder 2- SW Precision (Varget Clone; used Varget data with Barnes 120g)
same brass and components as above.
COAL - 3.110; OTB - 2.650 ( .080 off lands)
Lee FCD light crimp

starting charge 44.5g working up to 46.9g

44.5- 2908
45.0-3068
45.5-3146
46.0-3026
46.3- 3366
46.6-err
46.9-err
46.9-err

No pressure signs. Bolt lift fine.
Shots 2,4, and 5 clover leafed 1” high.
Shots 1,6,7,and 8 all within 1” of each other 1.5 inches right of bullseye.

Will load up 3 each of 46.6g, 46.8g, and 47.0g and shoot for groups.

Since my optical chrono can’t be trusted, I will use a Magnetospeed to determine velocity once I find a CW and seating depth that achieves 1 MOA or better.

One thing to note; the powder charges definitely don’t take up space I’m used to. Can feel the powder when you shake the round.

trying to find a load with a MV of 3100 fps or slower. Would like this to stay intact on impact.

Suggestions welcome.

 

[Roseaukaine]

Update; shaded my chronograph with cardboard and things are back to normal….another sunny day (Thanks X Man).

Loaded 3 each of the following and results;
Staball 6.5
Peterson Case
Fed 210m primer
COAL 3.140; OTB 2.675
120 CBB MKZ
.270 Win; 24” Barrel 1:10 5R - TC Venture.
Temp 77* Sea Level; Light breeze
Distance 100yds.

52.8g
3034
2998
3000
1.3 MOA group (may have pulled one)


53.0g
3039
3038
3029
0.64 MOA group

53.2g
3107
3067
3093
0.87 MOA group.

No flat primers nor bolt lift.
Will load up 5 at 53.0 and try to Verify.

If I had more bullets I’d experiment more with seating depth.
If I can get her to group at 3/4 MOA I’ll be happy. Then I’ll move on to working with the .308 and the 125 and 168 MKZ.

 

[Yamaraja]

Update; shaded my chronograph with cardboard and things are back to normal….another sunny day (Thanks X Man).

Loaded 3 each of the following and results;
Staball 6.5
Peterson Case
Fed 210m primer
COAL 3.140; OTB 2.675
120 CBB MKZ
.270 Win; 24” Barrel 1:10 5R - TC Venture.
Temp 77* Sea Level; Light breeze
Distance 100yds.

52.8g
3034
2998
3000
1.3 MOA group (may have pulled one)


53.0g
3039
3038
3029
0.64 MOA group

53.2g
3107
3067
3093
0.87 MOA group.

No flat primers nor bolt lift.
Will load up 5 at 53.0 and try to Verify.

If I had more bullets I’d experiment more with seating depth.
If I can get her to group at 3/4 MOA I’ll be happy. Then I’ll move on to working with the .308 and the 125 and 168 MKZ.

53 grains looks pretty good!

 

[Roseaukaine]

Quick update;
Was windy enough to blow my chrono over during testing so velocity data is incomplete, but I did some accuracy verification loads based on the information above.

Staball 6.5 powder at 53.0g; COAL 3.140, Lee FDC - light crimp
3015
3088
2998
err
2998

total group size was 1.5” but the conditions were not the best for accuracy testing.

Same powder charge, seated .015” shorter at 3.122; 1.2” 3 shot group. Chronograph blew over Before this group was shot.

Observation. Staball 6.5 is filthy. No, really filthy.

Had to test accuracy on the SW precision loads I wanted to verify so I shot the following charges just to see what, if any differences would occur;
3 shot groups; SW Precision powder; COAL - 3.110, Light crimp - Lee FCD

46.3g - 1”
46.6g - 0.86”
46.9g - 1.07”

interesting to note that all 9 of these shots were inside 1.5” total group size.

I have since loaded up some Remington 1x brass with H4350 and will run a ladder test starting at 51g moving up to 54g. Temps are in the upper 90s here now, so it’s not ideal, but will report back when I get the chance.

 

[earlytom]

Re the Chrono blowing over, we use stacked iron barbell weights tied to a small diameter eyebolt on the bottom of the tripods vertical upright on the Caldwells.

 

[snaz567]

I've used Staball in 6CRD & 260 Remington. It likes to be at or near max pressures in my experience before it really starts to shine. Great velocities and single digit SDs once it gets there. It is dirty tho compared to 4350, RL16, etc.