What caused this round to explode?

[Marinos]

I was shooting my homebuilt Ak when I heard something that sounded off. I stopped firing and inspected the gun. The gun was fine but this is what I found on the ground. The gun has close to 1,000 rounds through it but I checked the head spacing just in case. Everything was spot on. What do you think caused it?

[CAL.BAR]

IF everything else were the same about the gun, and you had no problems with other rounds, I'd say perhaps over pressure caused by an overloaded round. If it only happens once, I wouldn't worry too much about it. If it keeps happening, it's likely the rifle.

[LeadFarmer74]

7.62x39 is known to split around the neck sometimes.

[pacrat]

Crappy Ammo.

[JustEd]

Was this a reload, it looks like neck fatigue?

[LeadFarmer74]

Was this a reload, it looks like neck fatigue?

It's steel cased so that would be a no.

[Beelzy]

With steel cased ammo, that is a percentage of the norm.

[AKSOG]

likely the firing pin hitting the primer

[uxo2]

Normal with Steel cases.

It doesn't contract as well as brass.

[prod39]

It's a split case ! Happens,,,sometimes too many reloads, sometimes crappy case,,,no harm,,no foul,,,get back in the game !

[mosinnagantm9130]

With steel cased ammo, that is a percentage of the norm.

This^^

Happens every now and then with steel. Now, if it was happening every other round or something, it's probably a problem with the lot of ammo.

[JustEd]

It's steel cased so that would be a no.

I have more faith in the stupidity of some. Have seen several 45acp cases on the range just blown to shreds, albeit aluminum ones.

[Marinos]

Was this a reload, it looks like neck fatigue?

No. I'd never go through the effort to reload steel.

[ar15barrels]

It's steel cased so that would be a no.

How does the case being steel mean it's not a reload?

[LeadFarmer74]

How does the case being steel mean it's not a reload?

I assumed it was not a reload.