How fast is too fast for Barnes TSX bullets?

[Leatherneck556]

So I've seen several reports that pushing a TSX bullet too fast will cause the petals to shear off even if not going through windshield glass. The examples given were that SBRs pushing 55 and 53gr loads did just fine, but that 16" barrels pushing those rounds had problems with the petals shearing off. It is claimed that when you go to a 62gr round fired from a 16" barrel, that all the problems go away.

DocGKR and others, do you have any info on this? The spirit that I'm asking this in is that I'm wondering if there would be any benefit at all to a 5.56 pressure TSX load? If I had the option between 62gr TSX in 5.56 pressure or .223 pressure to act as my primary "defense" round for either an SBR or a 16" gun, would there be any reason to pick one over the other? More of a thought experiment than anything, I guess. Thanks.

[DRT]

I can tell you from personal experience that 5.56mm 70gr TSX at just over 2900fps MV out of my 20" AR15 lost 3 of 4 petals when fired into water at close range. BTW, my 20" 1:7 rifle shoots the SSA loads with reasonable combat accuracy, my 16" 1:7 carbine doesn't. Both shoot 5.56mm 75gr TAP very well.

[Pumpkinheaver]

Even if they come off they are going to travel a slight distance from the point of origin and continue to cause damage. I would rather have them stay with the main mass of the bullet but if they shed I wont loose any sleep over it.