The interlock is excellent. I used them for 10 years, 180grn 300wm.
I also used them for a few years in my 257R, 117grn.
I did try the 165grn SST, and it was the only bullet I've ever recovered from my 300wm, from both shoulders of a 10pt buck at 45yrds or so.
The Hornady custom factory loads with the interlock have been very accurate in everythhing I've shot them out of also. Great product.