Don't say it can't happen to you

[rtracy2001]

I will preface this with a disclaimer. I was loading jacketed bullets. Sorry, I like to shoot and I refuse to limit myself to just cast. Besides I am still not set up for 30 cal.

I was loading for my Mauser 98 in 308 win pictured below:
http://i156.photobucket.com/albums/t23/tracraym/finished308.jpg

I just finished building this rifle and prior to this morning I had shot only 20 rounds through it.

I was loading old Remington 150 gr spitzers using some mixed milsurp brass that I picked up at a local pawn. The brass had been resized and primed with CCI LR primers according to the tag.

I decided not to use the brass for load development because it had not been fired in my gun, so I picked a middle of the road load from my manual (Speer #11), 45 gr IMR4064. After loading two cases, I was not happy with how full they were (it was nearly a compressed load and it just didn't feel right. So I pulled the two cases i had already loaded aside, wrote 45 on the case with a sharpy and reset the scale to 43 gr. I figured I would try the 43 gr and if everything looked right, I would shoot 45 gr later.

Fast forward to the range. I set up to shoot and sight in my new-used scope that my brother gave me. Using the 43 gr loads I got the scope sighted in with no difficulties. Recoil was not abnormal, and the cases all looked good. In the course of sighing in the scope and plinking, I shot 20 of the 25 reloads without incident. Number 21 was not so lucky. Recoil was still in the normal range, but the report sounded funny and I got hit in the face with some hot gas. (no injuries, I wear glasses while shooting). (The shot never hit the paper BTW). I did a quick inspection of the rifle and could find nothing amiss. upon attempting to open the bolt I knew I had problems. The bolt finally opened after some persuasion with the plastic handle of my screwdriver. the case however stayed in the chamber, and the primer fell onto the bench. Except for the primer being on the bench it looked fairly normal.

A quick trip to the smith got the case out (it wouldn't come out with my rod, so I decided to let the expert do it). He also looked over the rifle and determined that it did not appear damaged. When I got back home I put the primer back into the case:
http://i156.photobucket.com/albums/t23/tracraym/050711113807.jpg

Not pretty.

I am by no means an expert, nor am I a complete novice as I have been reloading for about 20 years (started at 15). I consider myself fairly capable and cautions. Every rifle charge is weighed, I only have one powder on the bench at a time, and I double check scale zero before I start loading and after I am done. I have never had anything like this happen to me before and I am more than a bit embarrassed.

When I got home I pulled down the last 4 rounds. All remaining powder charges were as expected. This of course does not mean that the actual powder charge in the case abocve wasn't something else due to scale malfuntion (RCBS 502) or operator error (it is possible, but I don't think so). I also checked my load against the Hornady 7th ed. Hornady starts at 38.4 gr and goes up to 44.9 gr. So the 43 gr is not a starting load according to Hornady. Guess I need to order a new Speer manual.

[jblee10]

I usually try to stay with one brand of brass per cartridge. It's even better if I can stay with one lot of brass. At any rate I never mix brass, lot or brand. It's possible if you bought pre primed brass that the primers were mixed also. You could have had a weak primer shove the bullet into the rifling before the main charge ignited, boosting pressures.
Anyway, glad you were wearing glasses. Long ago I had a 22 lr round pierce a rim and put a tiny piece of metal in my right eye. The optometrist said it was best to leave it there and let it scar over and I still have it today. I learned my lesson of wearing glass with all firearms.

[felix]

Standard military custom target load years ago was 39 grains 4064, Winchester commercial cases, 168 BR Sierra, forgot the primer flavor. The person doing the contract loading for Fort Benning wrote it up for Handloader Magazine. ... felix

[R.M.]

When I first got my my 30-06 Rem pump, it came with enough reloading gear to get started. The manual was a Speer from the 70s. I chose a middle of the road load. First shot ejected the case, and when I picked it up, it burned my hand.
This taught me to cross-reference more than one manual.
I don't remember the specifics, but the gun wasn't harmed, and I shoot a different load now.

[Guesser]

That looks like a TW53 head stamp. Is the case a resized and shortened '06 case? If so then the neck thickness may be too much and could have contributed to excessive pressures. I have never seen military 308 cases as old as '53. Just speculating here!!!

[MtGun44]

I think guesser has the story. You were dealing with cut down Korean war vintage .30-06
brass, probably if you measure the water grains internal volume you will find it 10% or even
more lower volume than a normal .308 or 7.62 NATO case. I do not think any 7.62 NATO ammo
was made in that time frame at all - although possibly some experimental ammo for the
T44 (IIRC) prototype for the M14. It is very unlikely to be originally made as 7.62 NATO
cartridge.

Normal military cases are typically smaller in internal volume than commercial to start with,
and then throw in the reforming and you are likely much smaller volume. Your noticing
the extremely full nature of the charges was good.

Personally, my target load with the .308, using Fed match brass is 43.3 gr 4064 and 168
MKing. This is not a hot load but makes right at 2600 fps.

Good gun handled the gas properly, glad to hear no personal or equipment damage.

Take care.

Bill

[44man]

That is the elusive S.E.E. event. Both my friend and I had that with the 6.5 Swede's using 46 gr of 4831 and bullets too short.
It is not the brass or the load exactly. Look and see how much freebore the chamber has before the rifling. Chances are the bullet has a long way to move since most military rifles were made around very long bullets.
I would guess a bullet came out from a lack of tension or a primer with too much pressure before ignition, stopped and was slammed with full ignition. A bullet that stops out of the brass is a bore obstruction.
See if you can seat bullets within .020" of the rifling.
It is true that freebore reduces pressures like in the Weatherby rifles, however, the bullet MUST NOT MOVE before ignition.
Many will tell you it has not been proven or duplicated but you experienced it as we have. Is more proof needed? I know for a fact you will never load the same.

[felix]

Most definitely a SEE, 44man. But why did it occur? The other posts are shedding some light on that matter. I would rather think the SEE would be more emphasized with the H335s/BLCs, not with 4064!!! But, as usual, a SEE can happen at any time, any place, and for any reason unknown at the time of occurrence. ... felix

[Duckiller]

+1 for Guesser. While sorting through mixed brass I found a DEN 42 for .308. It went on the shelf with other oddities. Many people have modified military brass for different calibers. Unfortunately a military headstamp doesn't trigger an automatic 10% reduction in loads.
I would recommend that everyone acquire SEVERAL reloading manuals. One of the earlier bound Speer Manuals gave me a very hot load for .357. Now whenever working up a new load I cross check with several manuals. If one manual gives a higher load than the rest then it should be approached slowly and carefully.

[rtracy2001]

That looks like a TW53 head stamp. Is the case a resized and shortened '06 case? If so then the neck thickness may be too much and could have contributed to excessive pressures. I have never seen military 308 cases as old as '53. Just speculating here!!!

Sure enough a quck search revealed that the 308 Win or 7.62 NATO wasn't adopted until 1954 (As the T-65 round). Of course even then, there wern't guns to shoot it until 1957 when the M-14 was chambered for it, so a 53 headstamp would have started life as an '06. I see no reason not to use the remaining brass, but I think I will knock out the (now) questionable primers and start fresh. Will double check the neck thickness too.

I do have several manuals, but except for the Hornady they are all rather dated and seem to think that max loads with 4064 shold be somewhere around 47 to 50 grains. I am ordering a brand new Speer this weekend, and will probably retire the rest of my manuals once I have all the notes copied out of them.

Oh BTW, all 25 of the brass I loaded were the same TW53 headstamp.

[MtGun44]

If the necks are super thick from reforming without neck reaming, maybe it couldn't let
go of the bullet.

Bill

[frankenfab]

I think it was the brass, too.

Very nice looking rifle, by the way. I'm glad you and it were not injured.

[captaint]

If I had to make a WAG, it would be thick necks. My .02. Mike

[Bad Water Bill]

Sure enough a quck search revealed that the 308 Win or 7.62 NATO wasn't adopted until 1954 (As the T-65 round). Of course even then, there wern't guns to shoot it until 1957 when the M-14 was chambered for it, so a 53 headstamp would have started life as an '06. I see no reason not to use the remaining brass, but I think I will knock out the (now) questionable primers and start fresh. Will double check the neck thickness too.

I do have several manuals, but except for the Hornady they are all rather dated and seem to think that max loads with 4064 shold be somewhere around 47 to 50 grains. I am ordering a brand new Speer this weekend, and will probably retire the rest of my manuals once I have all the notes copied out of them.

Oh BTW, all 25 of the brass I loaded were the same TW53 headstamp.

Just found this

Miscellaneous Questions
Factory ammunition is made to give performance within the stated SAAMI specifications ... All 7.62 x 51 mm ammunition is non-corrosive with the exception of a single lot ... TW (Twin Cities Arsenal), M1911 Ball Lot 180000 (8/53), TW 54 ..... responsible for their own actions and who will sue anybody to make a buck. ...

Looks like there COULD be some 54 brass around in 7.62 X 51. I just checked my stash of 30=06 and found some T W 54 so If you really need to know the capacity of a conversion I can snail male you a couple and you can size them down etc and find out OR just throw out the questionable brass and be SAFE.

[leftiye]

Pinched case necks (brass too thick to fit in chamber)will blow primers on cue - every time, maybe even worse than that. Thick case with reduced capacity will do it too - but with that powder, and not being a compressed load? SEE would do AT LEAST that much damage, more likely probably destroy the rifle!

[rtracy2001]

OK, so rereading the posts I find SEE and S.E.E. Presumably the same thing, but what exactly is it?

I don't have a ball/neck micrometer, but a little work with the dial caliper showed measurements ranging between .015" and .018" thickness at the neck. All 20 rounds that performed properly and the one that blew out the primer. I also checked some PMC brass that I picked up at the range, some RP and FC cases that I had on hand. I also checked the remaining 25 TW52 cases that I have not loaded yet. All seemed to fall into the same range.

Another piece of info to consider, the barrel on the rifle started life as a Remington 700 in 30-06. It was shortened, retreaded to small ring mauser (Turk action, LR with SR threads). My smith did the final chambering.

I did not crimp these reloads. there was no cannelure so I relied on neck tension alone to hold them in place. Yes, I loaded 3-5 in the rifle at a time and shot groups of 3. This was the last one in the magazine.

I hope no one thinks I am dissmissing their suggestions. i want to try to figure out exactly what happened so I can take steps to prevent it from ever happening again.

[Jim]

SEE is "Secondary Explosion Effect". Felix would be the man to best explain it. Shoot him a PM, he's good about responding.

[1Shirt]

Looks to me like the brass is necked down 06 so agree with those of that opinion. I have and will probably continue to shoot mixed commercial brass if that is all I have, but will weigh and seperate by weight at least. Also agree with the review of more than one manual. Two or three are good, and more is even better.
It pays to compare. I have only resized a few cases in many years of shooting. Made a number of 243 our of 308 sucessfully, but that is a real pain in reaming the thick neck. Made a number of 270 from 06 Win brass, that did not require reaming and worked fine. Recently, made about 40 8x57 that are fine, but a pain to cut off and trim to right length, but opening up the neck rather than sizing it down not a problem, and they fire form well. Am very carefull about 8x57 made from 06 because of the possibility sticking one in an 06, however had few 8x57, and a lot of 06, so----.
1Shirt!:coffee:

[ole 5 hole group]

Thirty years ago I had a case that looked very similar to yours and a face full of powder and primer residue (stung like hell) – huge primer pocket. I suspect that load developed a lot of pressure in order to open up the primer pocket as much as you did. In my case, I damn near broke off the bolt using a 24” pipe to get enough leverage.

My case was a tight necked 6BR made from a small primer 308 case. I was loading max loads for a tight neck and I think my powder measure failed to throw all the powder on one charge (powder probably jammed up just above drop tube) and upon the next throw I got a charge and a half or more.

The Model 700 spoke with authority but incurred no ill effects except for the extractor. I’m sure it was an over max powder charge, as just before that round I experienced a much lighter load then normal, which opened my group up and then the boomer. I normally inspected my loads for powder column uniformity but must have been a little careless on that load sequence – haven’t been lax since.

[Bad Water Bill]

If you are concerned about the headstamp order this set.

http://www.riogrande.com/MemberArea/ProductPage.aspx?assetname=111344&category|category_root|120=Tools+and+Equipment&category|cat_120|344=Stamping+and+Chasing

When I made my 20 V T brass I used an I stamp to cover original mfgr headstamp then every 90 degrees put in the new headstamp.

Now when I am gone someone will definitely know this brass is NOT 223 even if they are a newbe. Yes I sleep better now.

[geargnasher]

My M70 has a .336" chamber neck diameter. Brass necks thicker than .0138" will bind upon firing with .308" J-words. If I use military brass with cast boolits, I have to turn the necks down.

Military .30-'06 sized to .308 will be even worse since the thick, large diameter part of the case is drawn down to form the new neck. If this wasn't reamed or turned down to correct dimensions by the person who formed it, then you'll have problems. Throw it out and get some commercial brass or military of the correct caliber and reduce the load appropriately for the case volume.

Gear