What happened?

[Jaxondog]

Could someone help with some ideas of what went wrong with this round.

once fired PMC brass [223 rem ]

primer pocket's swaged to remove crimp

55 gr. FMJ Rainier bullet

25grs AA2230

these rounds have a .006 jump to lands

This has happened 2 other times in different rifles. None where known to have a headspace problem but all were on the same brass [PMC]. I am now separating all PMC brass and loaded rounds as I have not a clue what has happened. Yes, it messed the bolt up pretty bad.

 

[jwrowland77]

Is this a different lot of powder from when you did the workup?

Did you happen to see any pressure signs when you did the original workup?

Did you change any components from the original workup?

That's all I can think of.

 

[FROGO207]

As stated if EVERYTHING remained constant and it was only the PMC brass you had problems with then you might have a bad batch of brass. Are you SURE that the propellant level was the same in ALL the rounds. Using a progressive and getting odd drops might be possible. Also did you measure the brass before reloading. Pinched necks will raise pressure dramatically also. You need to find out what happened and correct it now.

 

[edfardos]

Doe the flash hole seem large to you?

Hard brass cracked during swaging?

The brass/webbing seems fine, and the primer pocket failed?

Edfardos

 

[Walkalong]

You have to assume the brass is OK, and look for a problem that could cause high pressures.

.006 off the lands is simply not repeatable with 55 Gr FMJ bullets. The ogives are just not that consistent. Some may end up being into the lands. Into the lands is OK if the load is worked up that way. Trying to be close to the lands with a 55 gr FMJ is a waste of time anyway. They don't shoot well enough to worry with this.

It isn't a head space problem.

Doe the flash hole seem large to you?

Expanded from the same pressure that blew the case.

 

[James2]

Does the rifle completely support the brass when in firing position? Or is there a bit of the base not supported?

If the base is not completely supported it just blew out. A combo of rifle design, high pressure and weak brass.

 

[rcmodel]

Nobody's rifle design fully supports the case head 360 degrees all the way around if it has an extractor cut in the bolt.

And this looks like it came out of an AR-15 or something which does have an extractor cut in the bolt.

That ain't the problem.

rc

 

[hovercat]

The solution in this case is to sell the reloading equipment and use the proceeds to purchase factory ammo.
The third rifle? And you did not pull all the loaded rounds and begin back at the starting load after the first?

 

[gamestalker]

It's hard to say what the culprit was, but I would feel confident excessive pressures are what ultimately caused the case to let go.

Some things to check.

Measure the brass. Bottle necks that are in need of trimming and exceed maximum can pinch in the throat.

Check the powder charge weights in the remaining cartridges.

Check your scale, was it zeroed properly?

Did you charge with the wrong powder, more than one on the bench is often the cause of this mistake.

And .006" off the lands isn't wise with an AL rifle. Nothing much to be gained by this, but certainly much to be lost.

Are you certain that you used the correct weight bullets. A heavier bullet will absolutely create an excessive pressure situation.

GS

 

[243winxb]

25grs AA2230 is for a 5.56 chamber. There are AA2230-S and AA2230-C powders. Are you loading the correct one? What is the weight of the empty, deprimed PMC brass? There is bad brass out there in factory ammo & once fired. http://www.photobucket.com/kabooom

 

[M1key]

QUOTE: "25grs AA2230 is for a 5.56 chamber"

My data shows it is max load for a 223 chamber



Happened in 2 other rifles?

Brass is once-fired....ummm...in what? Machine gun?

Scrap the brass and start over with new brass or at least of known origin. I use Winchester, IMI, PPU, Lake City, and Federal (don't care for R-P). I have reloaded with some PMC, but only because I shot it new.

Good luck

M

 

[243winxb]

QUOTE: "25grs AA2230 is for a 5.56 chamber"

My data shows it is max load for a 223 chamber

http://www.accuratepowder.com/wp-content/uploads/2010/09/WP_LoadSpec_7-2-13.pdf The 223 rem maximum data is lower than 25gr, except for one bullet, if i look at it correctly.

This has happened 2 other times in different rifles.

If i had a few KABOOM before, i sure would change something. :banghead: 5.56mm Nato factory ammo is not to be shot in 223 Rem. Chamber. I would guess this applies to reloads, loaded to higher 5.56 pressures.

 

[Jaxondog]

First, I forgot to mention the rifle; Savage Axis Bolt action without accutrigger

I'm sure it is a different lot of powder as for the other two kabooms has been about 9 or 10 years ago. One was in a Howa, the other in a Rem 700. Both incidents were with PMC cases.

I have never loaded rifle cartridges in a progressive. All were loaded on a single stage, powder weighed on one of two digitals scales; Tact, and RCBS. After weighing set in loading block.

I have not checked the flash hole but I will.

Walkalong, you are correct. I'm just telling what I had at the time. This little rifle really liked 50-52 gr. bullets a lot.

Hovercat, I probably should not waste my time with your silly remark but I will. It has been years apart and thousands of rounds shot between the accidents.

Never more than one powder on the bench. Always use an orange sticker, [round] write what powder is being used on it and attach it to the lid on the powder scale.

243winxb, I'm sure after 9 years and thousands of round later there has been change. I'm well aware of the difference between the Nato and the 223 Rem. loads, as I am of all the different max loads for all the different manufacture of powder's and bullets of the same weight. You would think they would all agree.

Thanks for the replys, even the sarcastic one's.

 

[M1key]

Thank you

M

 

[joed]

You're loading to hot, plain and simple. Not all brass will hold the same amount of powder. Just because a load worked in one brand of case does not mean it will work in another brand of case.

 

[smokey262]

I agree with walkalong that 0.006 in. jump is way too long of a cartridge with that bullet. I bet the one that blew was jammed hard.

Another thing to check is to measure the diameter of the bullet with a 1 in. mic. Sometimes those plated bullets are a little generous in diameter.
Are they all 0.2240 in ?

Slightly larger diameter+cartridge with very little jump+near max charge=occasional kaboom

You could try re-seating them to about 0.020 in. jump, or if you are really itchy to use that length try starting out low again with a jammed bullet and see where the charge winds up.

 

[Walkalong]

Another thing to check, and it has been mentioned, is case weight. My plinking load is safe in any normal .223 case weight since I am using mixed brass. The occasional case where the powder comes up a lot higher in the neck get pulled out of the press and scrapped. There are some very heavy cases out there. Keep an eye out for them. This is for general shooting with mixed brass.

With a bolt gun where one is shooting a max load (Especially), and or shooting for accuracy, I would highly recommend using matching brass.

I have some 2230-S, and it is has its own personality.

Something happened, and since we were not there with it in a lab when it was shot, we have to give it our best guess to try to answer your question.

Looks like high pressure, and not bad brass, but it could be a soft head. Really no way to check that without testing the case.

 

[243winxb]

Testing Web Thickness

Testing the web thickness may tell us something. Over on AR15.com they test Federal brass. Some handloaders will not load the brass if under a set thickness. I made the tool, it works. http://www.ar15.com/mobile/topic.html?b=6&f=42&t=276154 See photos at link. Not mine.

 

[steve4102]

First, your bullet sounds suspect. I did not know Rainier manufactured any FMJ bullets. In fact I did not not they manufactured any .224 bullets.

If they are indeed Rainier bullets they may be plated. Pushing a plated rifle that fast is bad JuJu.

Next your load is over Max according to Accurate, couple that with the "plated" bullet pig jammed into the lands and you will get just what you got, an over pressure KB. Yes, your bullet is to close to the lands for an Over Max charge of any powder.

 

[Walkalong]

Very interesting thread 243winxb.

I am not familiar with that bullet, but yes, if that is a plated bullet, all bets are off for sure. If it is I would think they would give a warning.

Berrys sells a 55 Gr FMJ, but it is a jacketed bullet. It had to be loaded with a little lighter powder charge than the Winchesters I had been using, but shot better.

Anyone have a link to this Rainer bullet? I would think it was jacketed, or there would be bigger problems at that velocity. Maybe not, just seems reasonable.

 

[M1key]

Yes very interesting link about FC brass. Mine is all left over match brass and have never had a problem with it.

I didn't realize Rainer rifle bullets were plated? I have always avoided any plated bullets in pistol or rifle as I have read they can cause problems if driven too fast. But I have no personal experience with them.

All my 556 ARs and the 223 chambers I have (Tikka, Rem700T) shoot my favorite loads: 75 Hornady or 77 SMK, with a full charge of 24.5 gr of Varget and CCI400 or Fed Match primers, OAL of 2.26. I do not seat off the lands.

I use Winchester brass exclusively for the 223 chambers. This load occasionally will "lightly" flatten a primer in the bolt guns.

I have since moved on to 55 Vmax in 223 as they are a bit cheaper to shoot and I am getting good results.

M

 

[Jaxondog]

steve4102 you may be right about the Rainier bullet. I had Rainier pistol bullets on my mind while talking to a friend about his 10 mm and trying to type at same time. These three rounds I loaded the other day were Speer and as good as I can remember the other two incidents I was using Hornady bullets. Thanks for correcting that as I am not perfect.

Smokey262 and Walkalong; I thought about it last night and I'm leaning toward the .006 jump may be the culprit, or the case. I know that they were .006, .006, .007 cause I checked them as I do all my rounds when shooting for the same hole. I generally give .015 to .025 on the jump but this day I was reaching out maybe a little too far.lol. But then again, Why would all three times be on a PMC case. No I don't remember what loads I was using the two times before, other than they were 55 gr. bullets and the cases that blew were PMC.

 

[steve4102]

I didn't realize Rainer rifle bullets were plated?

Maybe they are not? I have never seen a Rainier Rifle bullet in .224, not in person and not on-line.

Someone show me a link to a Rainier .224 rifle bullet, please.

 

[jeeptim]

I have loaded lots of 223/5.56. Went through my pmc phase and I found the case heads to be soft this is commercial pmc the extractor tears it up upon thr second load signs of case head seperation I always load mid range and am very anal about case inspection I have found two out of maybe 10k with damaged heads maybe we shoot at the same range. This is what I think bad over charged mag primers out the box.

 

[Jaxondog]

I am inclined to agree with you also. I have decided to get rid of the PMC brass that I have wether it is the problem or not. I do feel it is partly the problem