primed mystery brass. what to do?

[tomtomz]

Dear Abby,

I bought some nice  300 WIN MAG brass on the forum,
and I'm pleased and have kudos for the seller.

Big surprise is that about 100 of them are primed with
a mystery primer, and the seller knows little about
The brass' history.

Short of chucking them in my rifle and checking them for
length and fit, I don't know if they are sized,
or if the primers have been contaminated.

80 grains of H1000 powder is rare and expensive.
Luckily I stocked up. This ammo is for my long-range
Shooter.

My buddy has a stainless Browning x-bolt and offered
to fire the rounds if I use the mystery primed
cases and charge them conservatively.
He's a good kind of crazy, and I don't
want to injure him or our long friendship.

What should I do?

[Graybeard]

Personally I would NOT assume anything of the primers. I would either fire them as is with no powder/bullet or just size/deprime them and start over. I wouldn't use powder and bullet cuz for all you know they might be large pistol primers not up to the task.

BTW I'm moving this to the correct forum.

[41 mag]

Like was mentioned, I would also simply deprime and start fresh.

A dozen or so years back I found a great buy on some "factory primed" cases for my 7mm RM. I figured they would at least work out for busting hogs or what not. About 1/3 of the first 50 I loaded went who knows where of the target, and had a totally different report than the others. I wasn't loading anything major, simply a 139gr Hornady over a mid range medium powder load. After that I just went about them as if they were once fired and ran them through the universal deprime and haven't looked back.

Even now when things are tough to find, it really isn't worth it to play guessing games with 60K of pressure 2" in front of your face.

[kynardsj]

I agree, pull the bullets and start all over. Be sure. I shoot my reloads and I have a good friend, I'll shoot his but if I end up with some in a trade from a stranger I will pull them and pack my own loads in them.

[Land_Owner]

GB has posted the most sensible recommendation, one that costs you about $4.00 for 100 new primers of known origin.  Here is another option.

Correct me if I am wrong, but the primers are one of three possibilities.  Large Pistol; Standard Rifle; or Magnum Rifle.  All are manufacturer unknown.

Load 3 cases with an accurate load for that rifle in a mid-range to reduced-charge of powder and a cheaper bullet.  Take a standard cleaning rod to the range.  If they are Large Pistol, you may need to push the first round out of the barrel, but you will know.  If the first fires OK, fire the 2nd for group.  If OK, fire the 3rd for group.  Check your group.  If the results are as expected, I would be comfortable with the entire lot.

GB make the sensible recommendation that for only $4.00, "why bother" with a stuck bullet in the barrel and the possibility of barrel damage trying to get it out.  My thinking stems from the premise that primers are primers are primers and there are none out that that explode and blow up guns on their own.  The possibility of a stuck bullet in the barrel is the nagging issue as well as their unknown origin and intended function (standard rifle or magnum).

[geezerbiker]

If they were large pistol primers they would be seated obviously too deep since large pistol primers are not as deep as large rifle primers.

The are sill unknown primers and unless they're the only ones you have, I wouldn't shoot them or only for plinking loads where a misfire isn't a big deal.  I was given a brick of 1968 large rifle primers back in the late 1980s and they hadn't been stored well.  I used them for target shooting but not for hunting.  I had about 2 or 3 % misfires with them but fortunately no hang-fires.  Remember to give a misfire 1 full minute not to go off.  I've not seen but I've hear some wicked stories about hang fires...

Tony

[ole 5 hole group]

If the primers are seated just below being flush, I would think they would be rifle primers and not pistol primers.  Being rifle primers, they would be either standard or magnum and I wouldn't think either one would cause you any concern with less than a max plus load. 
 
If you have any federal 215's on hand, I'd ease one of the primers out and compare the color mixture to your 215 - might be the same.
 
As for sizing - either try them in your rifle or remove the decapping rod from you sizing die, lube a case and see if they were only neck sized or if they are good to go.  My bet is everything is fine and they are good to go.     

[rmagill]

Not knowing how or if they were sized and having unknown primers I would just deprime/resize. Used brass from a different rifle needs to be full length resized and primers just don't cost that much.

[OldSchoolRanger]

Correct me if I am wrong, but the primers are one of three possibilities.  Large Pistol; Standard Rifle; or Magnum Rifle.  All are manufacturer unknown. ...

GB make the sensible recommendation that for only $4.00, "why bother" with a stuck bullet in the barrel and the possibility of barrel damage trying to get it out.  My thinking stems from the premise that primers are primers are primers and there are none out that that explode and blow up guns on their own.  The possibility of a stuck bullet in the barrel is the nagging issue as well as their unknown origin and intended function (standard rifle or magnum).

If they were large pistol primers they would be seated obviously too deep since large pistol primers are not as deep as large rifle primers.

The are sill unknown primers and unless they're the only ones you have, I wouldn't shoot them or only for plinking loads where a misfire isn't a big deal.  I was given a brick of 1968 large rifle primers back in the late 1980s and they hadn't been stored well.  I used them for target shooting but not for hunting.  I had about 2 or 3 % misfires with them but fortunately no hang-fires.  Remember to give a misfire 1 full minute not to go off.  I've not seen but I've hear some wicked stories about hang fires...

Tony

If the primers are seated just below being flush, I would think they would be rifle primers and not pistol primers.  Being rifle primers, they would be either standard or magnum and I wouldn't think either one would cause you any concern with less than a max plus load.  ...
 
As for sizing - either try them in your rifle or remove the decapping rod from you sizing die, lube a case and see if they were only neck sized or if they are good to go.  My bet is everything is fine and they are good to go.     

L_O, geezer, ole 5, all have good recommendations. 

I would first try chambering one or two cases (without powder or bullet), and fire them to see if they chamber properly and if the primers fire. 

Then I would decap all the cases with a universal decapping die.  Like geezer and ole 5 said, you can usually figure out if they're rifle or pistol primers, by looking at the height of the primers.    If your not sure of what a rifle primer should look like take a known pistol primer, and lay it along side one of the mystery primers, and make a comparison.  Once you know if it's a rifle or pistol primer, you can then probably figure out what make it is by the color of the primer, and priming compound side. 

Resize the cases, then reload them like you normally would.

[tomtomz]

We're on the same page. I have plenty of Magnum primers to do
The job.

To waste in a time of need counters how I was raised.

I'll deprime and work the cases as usual. I may need those primers
In the future, so I'll store them after decapping.

[squirrelslayer]

Huh!? why keep em if you don't know what they are? toss em man! Cheap insurance. What does one box of primers cost? 3,4,5 bucks?

[cudatruck]

you could load the cases with wax bullets and just shoot them. or load a few with light loads and cheap bullets test for fit and if all checks ok when done wouldn't they be fireformed to your gun?

[cjensen]

I would have had them sized and decapped before I could have typed out the question.
I don't save rusty bent nails either.

[SHOOTALL]

Most primers have a color under the anvil. Why not find a color code chart for primers and see what you have ? If the cup is brass or copper colored od silver colored and the primer compound is a certain color you can match it up in many cases though some may be difficult . I have punched many live primers out with my de capping die with no harm. But would not tell others what to do. If you are leary of doing so spray a little WD-40 in the case and let it sit over night.  You can find some charts in reloading manuals and maybe online . But like other if I could not ID I would hesitate to use them. Another mark would be a "B" on the primer then it would be a CCI bench rest primer.

[squirrelslayer]

I personally wouldn't want any wd-40 in any of my cases but to each their own I guess. I'd de-cap them pronto and be done with it. If you're worried about de-capping a live primer (I've pushed plenty out and never personally had one pop) set them off in you're gun before hand. Full length size is in order anyhow because You have no clue what has or hasn't been done to the cases.

[theratdog]

decap re-size reload primer's are cheap.

[gr8ful]

Personally I would NOT assume anything of the primers. I would either fire them as is with no powder/bullet or just size/deprime them and start over. I wouldn't use powder and bullet cuz for all you know they might be large pistol primers not up to the task.

BTW I'm moving this to the correct forum.

totally agree, why take the chance.

[SHOOTALL]

I personally wouldn't want any wd-40 in any of my cases but to each their own I guess SAC. one case if he was afraid to remove it hot. not a bad trade . . I'd de-cap them pronto and be done with it. If you're worried about de-capping a live primer (I've pushed plenty out and never personally had one pop) set them off in you're gun before hand. Full length size is in order anyhow because You have no clue what has or hasn't been done to the cases.

 
Even less expensive to ID what you have. But if you are not confident in your ability to ID the primers then for sure it is best to waste them and go on.

[Flynmoose]

I have removed a number of live primers with my universal decapping die. I never had one pop but put a heavy rag oner the top, just the same. I read somewhere that someone did a study about deactivating primers with different liquids....didn't work. Most of them went off as intended when manufactured.
FM