Odds of a round not going off but a good dent on a primer
 

Ok i was arguing god existing or not with a guy. Not my goal here lol

I told him about sonething that happen to me when i was 19
My dad and i was at a range. My ruger p89dc jammed bad. The slide was part back with a spent round stuck. I pulled pushed banged it for five minutes and while not paying attention i made what to the day was the biggest mistake with a firearm of my life. I had put the grip on the bench to gain leverage while pushing the slide back. The mistake was the barrel was pointed right at my face. I know dumb deadly and i was young dumb and been around firearms for not a year.
In the split second that i broke the slide free it ejected the spent jack the slide slipped my hand went forward racking the following round and my finger slipped pressing the trigger and click. Realizing what just happen i sat the gun down when i quit shaking i removed the mag figuring the chamber was empty i racked the slide and out pops a full metal jacketed unfired round. I started shaking again lol. When i picked up the round the primer was indented as it should but it did not go off

I told my dad who was in the booth next to me and the shop owner. Both agreed i was the luckest man alive in that moment

Well the guy i told this to swear primers fail all the time and fail to fire a round. Iv fired prob 25000-30000 rounds in my life this is the only time iv had it happen to me. I chuck it up to god really likes me.

So what are the odds of a primer being indented but not firing the round. Givin good quality ammo

Slim and none, with ol' Slim riding his hiorse out of town.

I have fired a gazzilion rounds .... rifle, shotgun, ML, pistol .... and can recall only 2 hang fires. One a 7 mm Rem. Mag. factory round and the other a ML inline primer that probably had gotten wet. You are one lucky dude!

I personally have never had a primer not go when the strike from the pin was a good one. More importantly though, when a firearm jams 1) point in a safe direction 2) put on safety if possible 3) drop the mag. Never ever point a weapon, loaded or unloaded, at yourself or someone else. Darwin's theory nearly came true.

Primer failure is not uncommon...I've been shooting for about 40 years now near weekly and wouldn't want to even try to guess how many rounds I've put down a barrel, but an average weekend I may have 1-2k pieces of spent brass to deal with. I can't count the # of failed primers I have had but it's been a fair number...most the time on a second attempt the primer fires...had two such incidents last week alone. 1 was a factory loaded round and 1 was a reload (Fed 210M)...and one was in a handgun and 1 in a rifle. It does happen...not often but not uncommon.

In 40 some years of shooting , hunting, handloading for almost everything I shoot, I've had exactly one primer failure. It was a CCI 250 primer in a 270 Win load.
It was a warm day and I'd taken good care in loading these rounds.
I lined up on a whitetail doe and squeezed off. Nothing but a click.
I was able to chamber a fresh round and kill the doe.
Why did that primer fail? No good reason except once in a while a bad primer just happens.

It's extremely rare but it happens.

Years ago during a handgun competition the front runner lost the match when one of the supplied rounds didn't go off. When they checked the round out they found the primer didn't have any priming compound at all in it. Basically is was just an empty metal disk. This was a factory shell by the way. I was about 10 or 12 when I read about it so that would have been about 1973.

I experienced nearly the same thing with a percussion cap on my muzzleloader once. I lined up on a decent mulie buck and all it did was go click when the hammer fell. I cocked it again and it went click again and the deer said bye-bye. When I took the cap off and looked at it, I noticed no priming compound in it either. I checked the rest of my caps and they were all fine. Murphy's Law dictated that particular cap was on the rifle while hunting and not of the range.

Primers are manufactured by the millions. Like anything coming off an assembly line there are going to be some defects and no quality control system will catch them all. It happens.

Never has a well struck primer ever failed. Ever. It was clearly Divine Intervention, you were spared because you have a greater purpose that you have not yet completed. Jump in front of a bus next week to prove it, you're untouchable until you complete your Divine Assignment. But after that, you better watch your back, Jack.

Seriously though, it happens. Luckily for you, it coincidentally happened right at a moment that turned out to be incredibly fortuitous for you.

But how do i not know between then and now i haven't completed it and thus the bus makes me a pancake lol

only 3 reasons a round won't go off
bad primer
no powder (this one is dangerous)
and a die set incorrectly
RR

4. Excessive case lube got inside the brass during sizing and contaminated the powder.

5. The primer got crushed too much during the priming operation.