300WSM, Barnes 180TTSX, Reloader 17

[Ronster]

I would like a good starting point for grains of powder (reloader 17) for a 300wsm shooting a 180TTSX Barnes bullet. Alliant shows thier recommendations of 66 gr for a 180SPBT speer, that is the closest info I can find to the Barnes TTSX.

On a side note, the OAL for my browning is 2.900 (with a .030 reduction recommended by barnes), however, my magazine will not hold over 2.855, what are your recommendations?

Thanks
Ron

 

[Ronster]

Bump for any info. Thanks in advance for your help.

 

[MontanaRifleman]

I think you're charting new waters.

I would start with 61 grains, work one grain at a time to 64, then a half grain up to max.

Am very interested to hear your results.

Cheers,

Mark

 

[Ronster]

Great, at -20 outside it might be a bit before I dedicate some time at the range. I will let you know how it turns out once it warms up.

 

[Ronster]

Today I loaded up some 300wsm rounds. I used Reloader 17 for the Barnes 180gr TTSX and Reloader 15 for the 168gr TTSX. For the reloader 17 loads I started at 62 gr and worked up to 67, for the reloader 15 rounds I started at 53 and ended at 59.

I bought a new chrony today so as soon as I get some warmer weather I will be trying this out. Chrony batteries and my fingers dont last long at the -20 range.

Ron

 

[7mm Eclipse]

My gunsmith recommended that I seat the Barnes TTSX bullets .050 off the lands in my 7mm WSM. This modification did more to tighten my groups that anything else I tried. Groups with the all copper bullet were in the > 1" category at settings of .020" and below. Setting the TTSX jump to .050" resulted in < 0.40 MOA. Maybe more jump may help with your 300 WSM.

This modification to your reloading could get you a bit lower than your 2.855" length clip restriction.

Mike