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« Last post by zonie on Yesterday at 04:54:57 PM »
A little trivia Barnes was not the only company to have relief cuts or relief grooves in their bullets. Barnes came out with the all copper X bullets no relief cuts it was noted not all rifles like them, then came the Barnes XLC bullets a coated bullet no relief cuts, Then the Barnes TSX followed by the TTSX both have relief cuts, my understanding machine made bullets with machine cuts, reasons to to reduce pressures by reduce bearing surface and reducing copper fouling. I know Barnes gives recommendations as to seating depths and these should probably be followed they have enough time in the seat with them to understand what's going on. My original TSX bullets when they first came out would place an amended load data statement inside each box of bullets, They haven't done that for quite a few years. The relief cuts on current 180 grain TTSX and my seating depth of 3.560 means not all relief cuts are inside the case the top relief cut on the 300 WBY and the TTSX -BT-180 grain is right at the top edge of the case totally outside the case when seated. It's not a problem it's where the cuts were positioned. As long as the COAL fits in the magazine freely and cycles correctly and the bullet is not jammed in the rifling you should be OK. There are 2 ways you can increase pressures from seating bullets at different coals , by seating bullets too long OR too short i.e. compressing the powder column or jamming the rifling.
buffby makes very good points. I don't know for sure how the Trophy Bonded Tip bullets are actually made since they are 2 different metals I have a good idea but that's about it. The bullet has a rear copper shank, front section lead under copper with a skived front with a polymer tip, followed by nickel plating, with relief cut/grooves and cannelure. Just my opinion I really don't think seating depth is a big deal so long as we follow a few rules, you don't jam the rifling when seating the bullet for length, (yes I know some bench shooters do it), I wouldn't seat the bullets too deep either, both ways you go can increase pressures, go with what the bullet makers recommends for seating depths to start with and work seating depths in and out as accuracy improves or degrades. Use a chronograph and watch for any velocity spikes and pressure signs.
Start with a lite powder charge (reloading 101) and work up. The original TBBC's (Trophy bonded bear claw) are very good bullets I don't know if the Trophy bonded tip bullets is a big improvement or not ? maybe ? Just don't go too overboard on excessive seating depths to start with.