Where do I seat the Barnes TSX, Tipped TSX and LRX bullets?
When loading a Barnes TSX, Tipped TSX or LRX bullet, your rifle may prefer a bullet jump of anywhere between .050” up to .250” or more. This distance off the lands (rifling), aka “jump” may be limited to the rifles throat length, magazine length and bullet length.
When selecting the cartridge overall length (COAL) Barnes recommend starting with a minimum “jump” of .050” off the lands. You can test different seating depths and find a “sweet spot” that your firearm prefers. Barnes suggest working in at least .025” increments as follows seating the bullet deeper to allow a further jump. Your test plan could look something like this:
1st group- .050” jump
2nd group- .075” jump
3rd group- .100” jump
4th group- .125” jump
5th group- .150“ jump
6th group- * see below
This length can be determined by using a "Hornady OAL Gauge" (formerly Stoney Point Gauge) or other methods. You do not have to seat the bullet at, or on one of the drive bands (cannelure) rings. Remember there are many factors that may control or limit the seating depth for your application. You may find that you need to start at around 0.150” off the lands and are not able to get any closer due to limiting factors including proper neck tension and magazine length.
*In rifles that have long throats you may be limited on how close you can get the bullet to the lands whilst maintaining a safe bullet length in the case neck. In these instances, it is not uncommon to find the best accuracy with a jump of .200” or more. In the case of a limited magazine length it is probably best to seat the bullet to the maximum cartridge overall length that it will safely hold and if necessary seat the bullet deeper into the case in small increments whilst checking for group size improvement.
This jump may possibly stay the same regardless of powder or charge weight within a given rifle. If preferred accuracy is not obtained, Barnes certainly recommend trying another powder, since the powder type and charge greatly affects the overall accuracy of each individual firearm.
FYI- An accurate load requires a bullet with the proper consistent case neck tension which leads to more constant pressures and velocities.