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tools2teach
10-04-2014, 11:00 AM
Can someone give me a logical explanation as to what might have happened with a reload?

I had a casing stuck in the extractor and had to shear off the casing from the bolt head using pliers. I also sheared off some metal from the bolt head in the process. I had to use pretty good force to turn the bolt handle upwards to remove the casing from the action.

Possible over pressure from a hot load, weakened brass? :confused:

Reload info
Rifle Remington 700 5R
308
Winchester brass - realoaded 4x
178 amax projectiles
42.5gr of H4895
Winchester LRP
OAL 2.810`

The damage
http://i730.photobucket.com/albums/ww304/tools2teach/Mobile%20Uploads/2014-10/902F5841-E4F8-4F32-9BD3-AF2B7127DE08.jpg (http://s730.photobucket.com/user/tools2teach/media/Mobile%20Uploads/2014-10/902F5841-E4F8-4F32-9BD3-AF2B7127DE08.jpg.html)
http://i730.photobucket.com/albums/ww304/tools2teach/Mobile%20Uploads/2014-10/B84F69FA-DE2D-4209-A2CF-16DCA2653DD3.jpg (http://s730.photobucket.com/user/tools2teach/media/Mobile%20Uploads/2014-10/B84F69FA-DE2D-4209-A2CF-16DCA2653DD3.jpg.html)
http://i730.photobucket.com/albums/ww304/tools2teach/Mobile%20Uploads/2014-10/0D1693A7-358A-4A03-987A-897DD97494D7.jpg (http://s730.photobucket.com/user/tools2teach/media/Mobile%20Uploads/2014-10/0D1693A7-358A-4A03-987A-897DD97494D7.jpg.html)

bsumoba
10-04-2014, 11:31 AM
the primer pocket ANd the primer pocket hole looks super blown out and super huge...looks like you might have had a loose pocket primer or primer hole (or lump this all into case head failure???) and just simply blew out all the propellant gases to the back, causing your failure.

your load seems to be fine. not hot by any means. The 4x firings is what hints to me what I indicated above.

if you are progressive reloading your ammo, i would recommend to stop using the primer seating function on the progressive and go manual. this will help you "feel" the primer as it seats into the brass and to make sure you have good primer tension/press fit.

you could also do more careful inspection of your brass during the cleaning process. when my brass starts to get into the 5+ firings, im meticulous about sorting brass and looking for defects.

hope this helps.

Spaceghost
10-04-2014, 11:31 AM
Do you recall a primer being easier to seat than others, when you reloaded this batch?

opos
10-04-2014, 12:03 PM
Looks like you could drive a car through that primer pocket..also maybe an over load if you use a powder drop and don't check loads...I'm a fussy old man and use a single stage press (for many years) and hand weigh on a 505 beam scale only...I prime with a Lee hand primer (the old kind with the round tray) for just the reason that it looks like here...I want to feel the primer being seated...Also ++++1 on really looking at brass when it gets over 3 loads ( in my case)...I seldom load past 3 loadings...I shoot 30-06, 8mm Mauser and 7.62x54r that I reload..and I don't load hot...but I also don't trust brass past 3 loadings. your mileage may vary.

toby
10-04-2014, 12:14 PM
I am going to say over loaded by accident, you got lucky!, this is one reason I load one at a time every time. I have never had this happen so it's only my thought but on the brass use of 5x I use brass up to 8-10 times.

Wrangler John
10-04-2014, 12:28 PM
First off, Winchester brass was tested against other brands and outperformed all others, including Lapua and Norma for longevity relative to numbers of reloads. This depends on whether or not the full length die was properly set to produce SAMMI specified cartridge headspace. Too much shoulder setback can reduce case life. Your case appears to be more than a head separation, more likely an overload.

Check your powder measure. Is it clean of any obstruction, grease or oil? There have been incidents where some form of contamination or an obstruction held back a quantity of powder (this is possible with both extruded and spherical powders) and then dumped it into one or more cases as they were loaded.

I had a small piece of the plastic canister seal that dropped into the powder unnoticed make its way into the measure to work as a flue dampener, holding a quantity of ball powder back then dropping both the new charge and the excess into a case. Took awhile to figure that out, fortunately I was using a single stage press and weigh every charge,

One other thing involves a progressive press. If a case doesn't pick up a primer and is loaded with powder and bullet, as the bullet is being seated air pressure from seating can drive a quantity of powder out of the flash hole, and subsequent handling can cause more to drop out. If the point is reached where the charge is REDUCED sufficiently, especially with medium to slow burning spherical powders, a pressure excursion can occur. Never, ever, hand prime a case that has been loaded without a primer present, you don't know how much powder was lost. Set the cartridge aside, pull the bullet, reclaim remaining powder and start over. A inadvertently reduced charge can cause enough pressure to destroy a case or blow up a rifle, and its completely random when it happens, sometimes nothing happens until the one time it does. In other words either too little or too much powder can raise havoc.

Also, using moderate charges of some medium to slow burning powders and the incorrect primer can cause pressure problems. I experienced this when I accidentally grabbed a tray of standard primers instead of magnum primers. Always read the recipe several times and check each component, as the mind can see what it expects not what you have in hand.

One last thing. I recommend that all Remington 700 bolts be modified by bushing the firing pin hole and reducing the firing pin diameter to 0.062". This will greatly improve the pressure handling ability of the rifle and eliminate cratered and pierced primers. I have all mine done by Greg Tannel: http://www.gretanrifles.com/services/viewEntry.jsf Video here: http://www.gretanrifles.com/services/viewEntry.jsf There are other smiths that do the same work.

Pauliedad
10-04-2014, 12:37 PM
Wrangler John,
Can you explain more about this firing pin bushing thing?

Car83
10-04-2014, 8:11 PM
Reload info
Rifle Remington 700 5R
308

Based upon your photo it looks as if you already had some work done to your rifle, 5 r's don't come with spiral fluted bolts.

Need more information.

What type of primer are you using?

Seating into the lands or off the lands? And how much?

How do you measure your OAL?
From projectile tip to primer? or bullet comparator?

Do you bump the shoulders or neck size only?

Do you uniform the primer pockets?

Deburring the flash hole?

bigbossman
10-04-2014, 8:16 PM
42.grs of H4895 in a 308 would be near case capacity, no? Can you get enough 4895 into a 308 case to cause that kind of over-pressure?

I don't know - just thinking out loud. I'm wondering if it might be something else, like maybe mixed/wrong powder, or bullet jammed into the lands.....

Car83
10-04-2014, 8:28 PM
Wrangler John,
Can you explain more about this firing pin bushing thing?

The hole in the bolt for the firing pin is much larger than the pin, allowing the primer to flow back into the recess.

The solution is to have a bushing put in the bolt face and drilled and reamed to exactly match the firing pin.

Car83
10-04-2014, 9:14 PM
You could just replace the bolt face.

bigedp51
10-04-2014, 10:09 PM
Very simple answer "OVER PRESSURE" and you exceeded the yield strength of the brass, meaning the chamber pressure was over proof pressure testing standards. "AND" you were very lucky you were unhurt.

The thumb rule is if the base just above the extractor groove expands .001 after firing you have reached the max load for that type/brand of cartridge case.
http://i122.photobucket.com/albums/o254/bigedp51/flow_zps2b838d87.gif

NOTE: Your case was loaded much, much "HOTTER" than the illustration above and the rear of your case looks like it tried to turn into a mushroom. :eek:

rm1911
10-04-2014, 10:15 PM
Pic 2 is the key. That case bulge. Way over pressure. The problem for you now is to trace down the cause.

Take all rounds from that load session and pull the bullets (you do have a bullet puller, no??) and weigh each charge.

Could be a one off thing. Or a bad piece of brass. Happens. Make sure each charge for the others is what you wanted it to be. And it's not off by any more than .1-.2 gr.

Then inspect all the brass. A good start is case length. You do trim the brass, right. Well, how many trimmings have they had?? Brass stretches. A couple of trims and it's usually near the end for it.

Either way te culprit is over pressure. The case bulge gives it away.

bigedp51
10-04-2014, 10:18 PM
First off, Winchester brass was tested against other brands and outperformed all others, including Lapua and Norma for longevity relative to numbers of reloads. This depends on whether or not the full length die was properly set to produce SAMMI specified cartridge headspace. Too much shoulder setback can reduce case life. Your case appears to be more than a head separation, more likely an overload.


I guess that depends on which test you read. ;) This test puts Winchester in fifth place "BEHIND" Lapua, Remington and Norma. And the best brass is Lake City 7.62 brass, because it is thicker and harder in the base than any commercial case made. And this is because it is designed to be fired in military chambers that are larger in diameter and have longer headspace settings.

Never say never.

The cases below were fired in a new Savage .308 rifle and full length resized with the press reaching cam over. (from Reloader Magazine)

http://i122.photobucket.com/albums/o254/bigedp51/308fail-1_zps30d387ab.jpg

http://i122.photobucket.com/albums/o254/bigedp51/308fail2-1_zps3ca31f6b.jpg

Whiterabbit
10-05-2014, 12:17 AM
Just a guess here, but based on the primer pocket hole, I'm wondering if this was a reloaded blank? I know 4x, but still, possible for a floater to get in the batch? What about annealing? did OP anneal his brass and let this one get too hot by accident, heated the base?

Just thinking out loud. I don't know his loading practices, and it's none of our business if he never admits all. But I'm hesitant to put it to bullet, primer, recipe or powder (unless he put the wrong powder in there).

Just brainstorming.

uniformed the primer hole with the wrong pin vise bit. Someone else uniformed the primer pocket hole and this piece of brass got in with his 4x pile (bad range pickup). Someone else was making 308 shotshells or un-folded blanks at the range and again unlucky range pickup. If we assume 65ksi and good loading practices, how else can the casehead fail like that? Gotta be either soft or the flash hole was already expanded.

FLIGHT762
10-05-2014, 7:53 AM
Somehow, too much powder or other contaminant, was loaded into the case. I would check your powder charging routine and try to find out how the case could have gotten over charged.

bruce381
10-05-2014, 8:00 PM
Lets see blown out WAY expanded primer pocket.
Has a belt like a belted mag but is not.
stuck bolt

yeah WAY WAY over pressure. wrong powder or way off headspace.
something is way wrong double cehck everything.

look how big the primer hole is and the pocket that over presure due to something maybe even bore ubstruction

bruce381
10-05-2014, 8:03 PM
my vote is wrong powder.

krwada
10-05-2014, 8:51 PM
Oh man!!! Your bolt looks ruined. You better have a qualified smith look at your receiver. It looks like overpressure. However; I have never seen overpressure do something like this before.

What I have seen however; is the wrong projectile do something like this.

Like a .311 seated instead of a .308

That just looks really bad. I am glad all you got out of this was a ruined bolt, and maybe a receiver.... this kind of failure could have really got you bad out at the range.

bruce381
10-06-2014, 5:35 PM
Just me but should you not figure out what went wrong first?
was the powder charge correct?
was the right powder used?
was the brass sized to much etc.