Scared myself tonight.... primer story

[VanMan]

I have accidentally fired off a round in my CZ SP01 Shadow while practicing lowering the hammer to decock it and that slide hit my thumb hard enough to break skin. That was a 9mm 124gr bullet with a muzzle speed of ~1150fps. The gun was pointed safely downrange, so the only thing hurt other than my thumb was my pride.

uhhh, it's like what, 180 grain pill and an unrestricted muzzle? We're talking about 10 or 12 lbs of recoil, not 10 tonnes. Has no one here ever tried thumbing the slide shut on their semi auto slide? Trust me when I say its anticlimactic, and quite predictable as to where the projectile goes (where ever it's aimed).

 

[j_06]

I suppose not, I've never fired a round on an open breach, I don't even think its possible unless something (lugs) are gone. I also don't think your 10 tonne press is anywhere near accurate. (pretty sure 10 tonnes would sheer those lugs clean off without even tickling the gauge.) It's not rocket science, but it is physics.

You guys say its a bad idea to try to seat the primer with the bolt, ok. Why?...and your 10 tonne analogy doesn't satisfy my valid question. I can't learn if you don't explain.

...and what is YKFS?

Here is a video of an Incorrectly assembled Ross rifle with no lug engagement being fired. Skip to 13:30. Yeah not a good idea to try and hold that closed

 

[william1]

Seemed like a Good Idea.

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[plinker 777]

Here is a video of an Incorrectly assembled Ross rifle with no lug engagement being fired. Skip to 13:30. Yeah not a good idea to try and hold that closed

Actually, thank you for posting this as I believe it half way proves what I was suspecting. There was no 10 or 12 tonnes of force imparted on the bolt, the only damage was the hardened (brittle) bolt lug breaking when it sped unimpeded back toward the bolt stop. Focus your eye on the butt stock to gain an understanding as to the recoil imparted on the rifle...it's actually minimal. I realize it's minimal because much of the energy is escaping to atmosphere as the bolt travels rearward, but I'm suggesting that if you were to hold that bolt closed you would not experience anything MORE than normal felt recoil focused on the area of the bolt handle directly to the palm of your hand. Would it bruise your hand? Probably. (I have shoulder bruises when I shoot many hi powered rounds or shotgun rounds). Would there be a 10's of thousands of pounds pipe bomb type death blast? Nope. The video all but proved it with a .303 British round which in my mind is comparable (I know someone will argue it but...) to the 30-06.

 

[william1]

So Bolt thrust from a 308 or a 30-06 is over 45000 Newtons.
Converted to pounds is over 10,000 pounds.
Or over 5 tons.
This is what I assume to be correct.
Info found at this link.

https://en.wikipedia.org/wiki/Bolt_thrust

I am no Physics expert, but what do you guy's think.

 

[TedNugent]

So Bolt thrust from a 308 or a 30-06 is over 45000 Newtons.
Converted to pounds is over 10,000 pounds.
Or over 5 tons.
This is what I assume to be correct.
Info found at this link.

https://en.wikipedia.org/wiki/Bolt_thrust

I am no Physics expert, but what do you guy's think.

Yup, if you scroll right on the chart under the "Estimating bolt thrust" link they provide, it is something like 10200 lb ft.
I think some people here are grossly underestimating the forces that the lugs undergo in preventing bolt movement.
I sure wouldn't want to be around anyone who thinks they are going to stop a bolt with any part of their body while I'm at the range.
Looky wasn't too far off, but really 5 tons, 10 tons, would a factor of 2 or even 10 really matter?

 

[Ar180shooter]

And I'm still using my old RCBS primer seater I bought in 1974, seat each primer and then flip the case and rub your finger over each seated primer.

This. I always check each primer with my finger to ensure it is fully seated, and I find I'll have to put one back in the press and squish it down a little more occasionally.