Bumping shoulder on loaded ammo

Billl223

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I've been reloading .233 competition ammo for decades but for some reason my last batch was slightly long on head space. Most run but a few are difficult to get chambered and when fired seem slow to eject. I re-lubed some rounds and bumped the shoulder getting them back in spec. I loaded a mag and ran the loads through the gun (no firing) with no issue. Is there any downside to bumping the shoulder on loaded rounds?
 

918v

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I've been reloading .233 competition ammo for decades but for some reason my last batch was slightly long on head space. Most run but a few are difficult to get chambered and when fired seem slow to eject. I re-lubed some rounds and bumped the shoulder getting them back in spec. I loaded a mag and ran the loads through the gun (no firing) with no issue. Is there any downside to bumping the shoulder on loaded rounds?
What die did you use for this???
 

1moaoff

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Depending on how many rounds you have that way...
Collet puller, pull bullets, bump, load bullet
 

Threadcutter308

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Personally, I would NEVER put a loaded round into any kind of die, particular one that could be used to bump shoulders. It is very unlikely that the top of the die has a larger ID than whatever the bullet diameter is. Provided that is true, there is nowhere for the bullet to go if ignition should occur. I think calling that a "dangerous situation" is a gross understatement.
 
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straightshooter1

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I've been reloading .233 competition ammo for decades but for some reason my last batch was slightly long on head space. Most run but a few are difficult to get chambered and when fired seem slow to eject. I re-lubed some rounds and bumped the shoulder getting them back in spec. I loaded a mag and ran the loads through the gun (no firing) with no issue. Is there any downside to bumping the shoulder on loaded rounds?
I've had a couple occasions where I've bumped the shoulder's of some of my loaded .308 cartridges and had NO problem doing it with Forster's Bump Neck Sizing Die and with its spindle assembly removed. Bumped the shoulder .002 with no other effects on the case.
 
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spife7980

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Personally, I would NEVER put a loaded round into any kind of die, particular one that could be used to bump shoulders. It is very unlikely that the top of the die has a larger ID than whatever the bullet diameter is. Provided that is true, there is nowhere for the bullet to go if ignition should occur. I think calling that a "dangerous situation" is a gross understatement.
If it’s a body die or a stripped bushing die it’s open trough the top.
 
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Mad_Charlie

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Some time back I had a case of PPU Match in 308 that was too long to chamber without really cranking on my bolt. Not wanting to use my rifle as a sizing die, I used my Redding type S with the guts out to bump the shoulders back about 4 thou. Worked like a champ, but I was pretty apprehensive when I started on them, even though I couldn't see how they could fire. YMMV. I don't have a nail in my press.
 

squib

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Thanks all for the advice, I bumped the shoulder on 50 rounds and took them to the range to test. My headspace issue seems to be resolved. Bumped another 300 rounds today with no issues.
I love a happy ending you got a bump without a boom(y)
 

SNOW JW

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I would be curious what would happen if a round went off.
 

Downtown

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Well, if the top of the die was open, hopefully just a hole in the roof. Otherwise, it would not be very pretty at all.
 

pmclaine

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I would be curious what would happen if a round went off.

probably SAME THING THAT HAPPENED WHEN I HAD A STACK OF PRIMERS GO IN MY Dillon,

Loud noise, dent in the ceiling, operator in dumbfounded shock, change underwear, carry on.


(sorry about the caps, must have ND'd the cap lock key)
 

pmclaine

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Why would the round go off?
Its like a diesel engine.....compression causes heat/detonation.


Once upon a time when I was a yut, we would go to a farm in western MA and all would party.

The place had to be winterized, no running water and we got heat from a giant fireplace.

Being fun loving I would take a 30-06 in my hand while cupping a small Chinese lady finger firecracker and pretend to throw the round into the fire but only let the little lady finger go.

The fire cracker would make a small bang.

Well one of the chicks decided to throw a 30-06 in the fire.

We were sitting there playing cards and a much louder bang occurred throwing sparks all over the hearth followed by the sound of something hitting the ceiling and the "tinkle" of brass skidding across the floor.

No real damage. The brass made a slight impression in the ceilingand the bullet probably just stayed in place in the fire.

You just cant have any fun around some people.
 
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Tokay444

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Personally, I would NEVER put a loaded round into any kind of die, particular one that could be used to bump shoulders. It is very unlikely that the top of the die has a larger ID than whatever the bullet diameter is. Provided that is true, there is nowhere for the bullet to go if ignition should occur. I think calling that a "dangerous situation" is a gross understatement.
How would the top of the die not have a larger diameter than a bullet for that caliber, when it’s designed for the neck of the case to pass through? Is the case neck on your brass not bigger than the bullets you load into them?
 

918v

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Compression in a sizing die does not cause heat. You can take a primer and crush it with a pair of pliers and it won’t go off. Primers need a hard strike in order to fire.
 
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Tokay444

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Its like a diesel engine.....compression causes heat/detonation.


Once upon a time when I was a yut, we would go to a farm in western MA and all would party.

The place had to be winterized, no running water and we got heat from a giant fireplace.

Being fun loving I would take a 30-06 in my hand while cupping a small Chinese lady finger firecracker and pretend to throw the round into the fire but only let the little lady finger go.

The fire cracker would make a small bang.

Well one of the chicks decided to throw a 30-06 in the fire.

We were sitting there playing cards and a much louder bang occurred throwing sparks all over the hearth followed by the sound of something hitting the ceiling and the "tinkle" of brass skidding across the floor.

No real damage. The brass made a slight impression in the ceilingand the bullet probably just stayed in place in the fire.

You just cant have any fun around some people.
Bullets don’t work like that.
have you not seen all the videos of people taking propane torches to the side of loaded cases? The propellant doesn’t ignite until the case melts through. This is why we use primers as catalyst. It’s also why we don’t used fucking diesel.
 

pmclaine

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Compression in a sizing die does not cause heat. You can take a primer and crush it with a pair of pliers and it won’t go off. Primers need a hard strike in order to fire.
When Im bored I take chunks of carbon and run them through my Dillon to make diamonds.

Its not for everybody, you need to have the Bis to make it work.......Pussys!
 
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pmclaine

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Bullets don’t work like that.
have you not seen all the videos of people taking propane torches to the side of loaded cases? The propellant doesn’t ignite until the case melts through. This is why we use primers as catalyst. It’s also why we don’t used fucking diesel.

I guarantee you a cartridge in a fire will cook off.

Its not a high pressure event like actually firing a round in a chamber. Firing a hot MG can cause rounds to cook off from just being in the hot chamber, very dangerous and you better have your immediate action to twist the belt and get shit in control fast.

I think the danger is on the scale of lighting bottle rockets without a stabilizer....never know where things will go......you could take your eye out!

On the serious side though have a small house fire and if the department hears one round cook off they will retreat and watch your house become a foundation.

Co worker had a fire in a car on the highway and some small amount of ammo cooked off. he turned it into the battle of Gettysburg in his radio calls - a total nothing burger but some people like to make a big deal out of shit.
 

918v

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I don’t know where you get that. You’re spreading bs. I called you out on it. And now you’re trying to insult me. Says a lot about you.
 

pmclaine

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I don’t know where you get that. You’re spreading bs. I called you out on it. And now you’re trying to insult me. Says a lot about you.
Your Aspergers is showing........
 

Tokay444

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I guarantee you a cartridge in a fire will cook off.

Its not a high pressure event like actually firing a round in a chamber. Firing a hot MG can cause rounds to cook off from just being in the hot chamber, very dangerous and you better have your immediate action to twist the belt and get shit in control fast.

I think the danger is on the scale of lighting bottle rockets without a stabilizer....never know where things will go......you could take your eye out!

On the serious side though have a small house fire and if the department hears one round cook off they will retreat and watch your house become a foundation.

Co worker had a fire in a car on the highway and some small amount of ammo cooked off. he turned it into the battle of Gettysburg in his radio calls - a total nothing burger but some people like to make a big deal out of shit.
I’m failing to see the correlation you’re trying to make between bumping the shoulder of a loaded cartridge, and throwing it in a fire, unless you’re trying to tell us that the pressure from bumping the shoulder generates enough heat to melt the brass and ignite the propellant. In which case I’m just going to laugh.
 

pmclaine

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Okay people....

I do not believe that sizing a loaded round will cause a round to cook off from "compression". There are no glow plugs silly!

Nor do I make diamonds in my press with lumps of carbon.

There is no Santa Claus either.

Sorry to be the one to break that to some of you but its true. Truth be told I was happy to tell you the last one.

OP Im glad your resize worked. I would have done exactly the same. Ive read of its success previously.
 

Snuby642

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Are you not ruining neck tension by doing that?

I run 0.0035 neck tension and a light to medium crimp on 223 ar rounds.

So the neck and bullet would be crushed back down .0035 ?
 

Snuby642

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Never mind, I forget about bushing dies since I dont use them.


DUH
 

Snuby642

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Thanks.

I only use fls dies on 223 since we have many 223 guns and also load range brass.

So I forget about other dies.

I have 308 neck die but never learned how to get any improved results over the 0.0015 bump on fls die so it sits it out for now.

In fact I want to get a 223 bolt gun chambered like our gassers so the brass can stay the same.