Reloading the new Barnes TSX offers a few interesting challenges. The number one thing to get you is that they are very long for their weight, and can take up a lot of powder space in some calibers.

I have been reloading the 375 H&H for nearly 30 years, mostly with 300 gr Hornady’s and Trophy Bonded Bear Claws.

The 375 H&H has been a very forgiving cartridge to load, with adequate powder capacity as compared to the inadequate volume of the 458 Win.

As with many things in life, the minute I think I got things figured out, suddenly I find I don’t know it all, “yet”.

The 375 H&H has been very easy to reload, as it will take IMR 4064 or IMR 4895, IMR 4320, IMR 4350, Rel 19, AA 2520 or AA 2700 and pretty much just does what you want it to do.

This was with standard bullets with lead cores. Now with the new Barnes TSX bullets (and older X bullets) all the rules changed.

Suddenly case capacity is a factor. I started tinkering with the 300 Gr TSX, not giving the length too much thought, as I had previously been shooting the 270 gr X bullets and never had a problem.

This was because the 270 gr X bullet is about the same length as the 300 gr standard pointed bullet.

The 300 gr TSX is a very long bullet (1.492 to be exact). While a 300 gr Hornady SPBT is 1.333 long, and a 300 gr RN is only 1.260

I found that when I took my favorite load of 74 gr of AA 2700, the 300 gr TSX actually was compressing the powder little bit, and pushed the bullet back out of the case after seating it.

At first I thought I did not have enough neck tension, so I resized the cases with the expander button removed to get a tighter fit. This helped some, but did not solve it.

Then I took the cases with only powder in them, and gently touched them on my vibrating case cleaner so the vibration would maybe settle the powder a little bit. This seemed to be the answer, as now the bullets would stay put.

Just to be sure, I then crimped it with a Lee factory crimper.

Using volume as a measurement, I found that 74 gr of AA 2700 is equal to:

66 gr of AA 4350 which is way light, as 75 gr is Max.

71 gr of W 760 which is better, but 77 gr is Max.

68 gr of IMR 4895 too much powder, as 61 gr is MAX

69 gr of Rel 15 would also work well as 70 gr is MAX

67 gr of IMR 4831 no good at all as 80 gr is MAX.

So if we stick with using the AA 2700, Rel 15, or maybe the W 760 and then vibrate the cases after charging, and finally seating that long 300 gr TSX bullet. Things should work just fine.

Unless you absolutely need to shoot the 300 gr TSX, just stick with the shorter 270 gr TSX. It solves plenty of the powder capacity problems, goes slightly faster, and I doubt if any Buffalo or Eland will ever know the difference.

Another case that will give you problems is the 300 Win Mag with its really short neck. It will work just fine with 165 gr TSX and 180 TSX will work also. But the 200 gr TSX are again, very long, and protruds deep into the power space.

The 300 WBY Magnums, is just the ticket for those long TSX bullets. The 200 gr TSX fits perfectly as well as 180 gr TSX.

The 270 Winchester works well with the 140 gr TSX or lighter, but the 150 gr is again, too long.

The 308 Winchester is fine with 150 gr TSX and the 168 gr TSX is perfect, but the 180 gr TSX is too long.

All sorts of examples can be made, and I’ve just included a few. Feel free to write me anytime for further assistance at tblauwkamp@superior-sales.com