What makes a bullet 'blow up' in flight?

[Dunraven]

Saw this at a match, where bullets were seemingly exploding into a puff, downrange maybe 100 yards.

 

[hafejd30]

Pushing a bullet to fast. Bullet becomes unstable due to twist in the barrel/speed.

One of the guys I shoot with in fclass has this issue if he pushes his 7mm Berger’s up around 3500+

Essentially the jacket comes apart

 

[Gunfighter14e2]

Simple,....Very high Rotational spin, that exceeds the ability of the jacket to contain the lead core.

 

[Dunraven]

Simple,....Very high Rotational spin, that exceeds the ability of the jacket to contain the lead core.

nothing to do with defective bullets, then? simply speed? twist rate too great?

 

[MarinePMI]

Usually it's just speed, but defective jackets, a bad crown, or horrible TIR can cause it as well....

 

[Gunfighter14e2]

More Muzzle speed increases spin rate, an with fast twist barrels the end product can over come the jackets ability to contain the lead core. some Target copper/lead bullets, are more prone than others. Most call it turning them into pie,... much like pumpkin chucking events.

 

[Dunraven]

makes sense. thx

 

[Steel head]

Pushing a bullet to fast. Bullet becomes unstable due to twist in the barrel/speed.

One of the guys I shoot with in fclass has this issue if he pushes his 7mm Berger’s up around 3500+

Essentially the jacket comes apart

I can tell you 7mm 180 eldm’s don’t like 2900+ with my 1-8 twist barrel.

 

[Steel head]

I might have some video from yesterday of the sound difference when 180’s blow.

I’ll look tonight.