I gotta know

[Bowanna]

Has anyone ever had the issue of after a day in the field you get back to your car, camp, home.... and you unload your rifle and the round comes apart ejecting the casing but leaving the bullet in the chamber. I've had it happen twice this month and never in my 50+ years of firearms experience have I had or heard of this happening.
I emailed the manufacturer and a tech responded with " ammunition is not to be rechambered according to SAAMI." I thought, Im supposed to treat my centerfires like my muzzleloaders and just discard them or shoot them out, at the price of ammo these days, I don't think so. And if it is the case why are there not warnings on the boxes, they got warnings for everything else imaginable.
I've sworn by this manufacturer for years but I think just to see what happens ill try another brand because I think someone's bulls#%$×* me!
If this has happened to anyone else then I wont be quite so upset about spending 2½ hours getting sunburnt powder out of every crack and crevice in my rifle.

 

[LOLBELL]

Just a wild guess but it sounds like the bullet is jamming in the lands and sticking when ejected.

 

[FatDog]

I have never heard of that happening. Sounds like the bullets do not meet SAAMI specs for that round and the OAL is incorrect. Look up the SAAMI specs and then check the remaining rounds from that manufacturer. Let us know what you find.

 

[Pappy John]

I've been rechambering ammo my entire life and never ran into that. I think the FatDog will prove to be correct.

 

[FatDog]

I have a question for you,, Bowanna. Did it take unusual force to chamber the round? I ask because as someone who reloads I've often had to disassemble a round. Properly seated and crimped bullets do not want to be disassembled. So if the brass is pulled away from the bullet then the bullet is seriously jammed into the lands, which means it took unusual force to chamber the round.

 

[Bowanna]

I have never heard of that happening. Sounds like the bullets do not meet SAAMI specs for that round and the OAL is incorrect. Look up the SAAMI specs and then check the remaining rounds from that manufacturer. Let us know what you find.

I have a question for you,, Bowanna. Did it take unusual force to chamber the round? I ask because as someone who reloads I've often had to disassemble a round. Properly seated and crimped bullets do not want to be disassembled. So if the brass is pulled away from the bullet then the bullet is seriously jammed into the lands, which means it took unusual force to chamber the round.

No sir, there was no force involved I simply released the carrier and it went into battery as it should and always does.
Now , since i started this thread it happened again with a different box of ammo but after checking i found they were of different lot numbers so I took calipers in hand and did as FatDog suggested. I measured 3 rounds from each box, 2 of th4 boxes had the rounds in question in them and the third box they sent me after my contacting them about the first incident. SAAMI specs for .450 Bushmaster are: case length- 1.70
OAL- 2.125-2.260
Bullet dia.- .452
My calipers are calibrated to +/- .001.
I had three of 9 rounds with case length slightly above specs, 1.704, 1.709, 1.710 for case length, all were below specs with 2.229 being the longest for OAL and all 9 were money at .452 for bullet diameter.
I checked the head space in my rifle which checked out ok the retrieved bullets had no visible lands marks as all were below OAL specs and were relat8vely easy to push out of the breech.( the second one for lack of a cleaning rod i used a coat hanger and very gently pushed the bullet out) So now this leaves me at wits end, anymore suggestions. Im looking for another manufacturer but a couple of other well knowns are outrageously priced, i can get ammo for my 50 Beowulf cheaper.
The round has a cannelure and if the case mouth is crimped properly this shouldn't occur, hell if it is the crimp snd the round gets pushed in farther due to recoil or striking the feed ramp that could cause a spike in pressure and......

 

[FatDog]

I'm stumped, Bowanna. I can't understand what part of the rifle's chamber/barrel was gripping the bullet firmly enough that the case could be pulled away from the bullet, Please let us know if you ever find out the answer.

 

[Bowanna]

I dont know either FatDog but the tech from Hornady said it was a widely know issue especially with straight wall cartridges but also with others enough so as to have SAAMI publish it. Now i believe SAAMI is nothing more than a group of, as the name implies, Arms and Ammo manufactures institute fellas just keeping their story straight. And if this is normal then something is wrong at the engineeting end of things. How does a round just pull apart bevause you rechambered it? Now i wonder if the free box of ammo was to shut me up.
Anyway, on to the next great adventure!

 

[FatDog]

I find the whole thing more than a little frightening. Like you said, it would be too easy for the bullet to move down in the case and create undo pressure. On the other hand, if the crimp was so weak the bullet could be easily unseated, then you'd get a ton of blow by, which should be evident in heat scorched hulls with tons burnt powder on them. I would definitely switch to another brand of ammo. Better yet, load your own.