Reports on the Barnes TSX in 300 win mag w/details???

[sunny]

Am considering Barnes new TSX bullets in my custom 300 win mag.  Would appreciate detailed pet load information, including recommended powders with starting and max loads for the 165 & 180 grain TSX's, in addition to primer & cases used, your group sizes & copper fouling.  I must say that I am a bit nervous about not being able to refer to a Barnes Manual for these TSX bullets.

[Coyote Hunter]

Am considering Barnes new TSX bullets in my custom 300 win mag.  Would appreciate detailed pet load information, including recommended powders with starting and max loads for the 165 & 180 grain TSX's, in addition to primer & cases used, your group sizes & copper fouling.  I must say that I am a bit nervous about not being able to refer to a Barnes Manual for these TSX bullets.

Sunny –

Barnes says you can use ‘X’ data and increase the max load by 2.0g powder.  However, I’m a big believer in people using chronographs whenever they approach maximum listed loads and would highly recommend using one for TSX development.

So far I have used the 115g TSX in my .257 Roberts and the 180g TSX in my .300 Win Mag.  Just paper and steel so far, but the results with both rifles has been outstanding in terms of velocity, accuracy and consistency.  At 200 yards the .257 has a propensity to shoot the flat center out of clay pigeons without breaking the rim.

For the .300 I have tried Retumbo, H1000, RL25, H4831SC and H4350.  RL25 and Retumbo were too slow and I ran out of powder space before I got the velocity I wanted.  H1000 and H4831SC were flattening primers before I got the velocity I wanted.  H4350, however, worked out great.

Here’s the formula I’ve been using:

WW brass trimmed to minimum length
CCI 250 primer
71.0g H4350
180g TSX, COL 3.316”, roll crimp
3063fps, 4-shot average
7.0fps Standard Deviation (STD)
15fps Extreme Spread (ES)

I actually got better groups at 70.0 and 70.5g H4350 but STD and ES were greater and I think the wind was the culprit on the group sizes.   A load of 71.5g H4350 (3074fps) gave me even lower STD and ES with no further increase in group size.  No sticky extraction or flattened primers with these loads.

[sunny]

Coyote -

Thank you for the very informative & detailed info... just what I was looking for.  I do have & use a chrony for the obvious reasons, however, as previously addressed, I've never developed loads without a manual before!  How was the copper fouling with the TSX bullets?