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Sundo
12-25-2011, 02:23 AM
I'm just getting started in reloading. I seated primers for the first time using the Lee Challenger press.

I measured my primer seating depth and compared it to the depth on factory loaded ammo. It turns out my reloaded primers are seated at double the depth of the factory seated primers.

What is the maximum seating depth for primers? Will my double depth seated primers work as is? Can I remove the primers and seat new primers, or should I just throw out the cases altogether?

Background info: Cases are once-fired Federal American Eagle .30-06 M1 (150 gr FMJ with reduced velocity). Rifle is 116 FCSS .30-06. Cases have been neck resized with Lee collet dies.

helotaxi
12-25-2011, 05:57 AM
Take 5 of the cases, charge them with powder and seat a bullet. Use a starting powder charge because you're only checking for function. Fire them. If they go bang, use up the ones you have seated and don't be so forceful the next time around.

There is no "max" depth per se, but you don't want to completely crush the primer. Ideally, the primer should end up right around 0.005" below flush with the case head. If you're seating them much deeper than that, you're likely ruining them or have the wrong primer (large pistol instead of large rifle).

Whatever you decide to do, don't scrap the brass. You can decap live primers without issue. Wear eye protection just in case, and simply run them through the size die (lube the case) or better yet a universal decapping die. Be gentle. You don't want the decapping pin to make a sharp connection with the primer anvil, but steady pressure wil push the primer out without much risk at all of setting one off.

Dennis
12-25-2011, 08:57 AM
A couple of drops of water or better, transmission oil dropped inside the case on the primer "kills" the primer!

Personally, I just take a few drops of water, drop on the live primer, decap the live primer, and never had a problem!

bigedp51
12-25-2011, 09:00 AM
I do not use the press to seat my primers I use a hand tool and go by feel, as soon as the primer anvil touches the bottom of the cartridge primer pocket you can "feel" it "stop" and you just give it a slight bit more pressure for a firm seating "WITHOUT" crushing the primer and doing damage.

SAAMI Large Rifle primer pocket depth is .128" to .132" and primer hight varies so keep this in mind when checking and inspecting primer seating depth in your cases unless you uniform the primer pockets and measure your primer hight before seating.



Primers - Large Rifle Primer Study
A Match Primer Study in the 30-06 Cartridge
By German A. Salazar
http://riflemansjournal.blogspot.com/2009/06/primers-large-rifle-primer-study.htm

earl39
12-25-2011, 11:51 AM
If it worries you that much take the one with the primer seated deepest and try it. Unloaded of course. makes a little pop not quite as loud as a small firecracker. If it goes off you should be good to go. Many of us loaded for years with nothing but the press to put in primers. unless you are really trying to crush them i doubt they are hurt and if they are too deep for the firing pin to hit them them i would think something is wrong with the brass. Take a used primer and set it on a hard surface then lay something hard and big enough to stand on on top of it and stand on it. Odds are the primer will not deform and if you weigh 200 pounds you are putting way more than 200psi on the primer. All i am saying is primers are a lot tougher than most people want to belive.

barrel-nut
12-26-2011, 12:16 AM
If it worries you that much take the one with the primer seated deepest and try it. Unloaded of course. makes a little pop not quite as loud as a small firecracker. If it goes off you should be good to go.



+1

fyimo
12-29-2011, 12:22 AM
I've been reloading rifle and pistol ammo since the early 80's and I've never had a primer seating problem seating them in my RCBS Rockchucker press and I'm sure my primer feeding does very some as my only check is to make sure they are not sticking up above the base of the case. They all go bang and so I guess I don't see the problem here.

Sundo
12-30-2011, 12:16 AM
I figured out what happened.

It looks like the Federal American Eagle .30-06 M1 cartridge cases have crimped primer pockets. I didn't realize this and seated away with the primers. With most of the primer seatings, a normal force on the press only partially inserted the primer. Using a lot of force, I heard an unexpected crunch and found the primers seated too deep. I suspect the primers are crushed.

First, I think I'll just toss out these cases. I don't think they're worth saving. What's the simplest way to ensure the primers are deactivated? I heard oil works. Can I just spray the inside of the case with Remoil, using the tube to get it into the primer?

Second, I wonder if the Federal American Each .30-06 M1 cases are worth de-crimping. I do have a primer pocket swager, but not sure if it's worth the effort.

Should I be concerned at all the the extra force I used to crush the primers with my reloading press might have caused any damage to the reloading press? Later loads (with uncrimped primer pockets) shot fine, as far as I can tell. I did damage the primer seater, but that's a cheap part that is easily replaced.

fyimo
12-30-2011, 12:29 AM
Your reloading press should not be damaged from crushed primers. I'm not sure how to deactivate primers but I'm sure oil or solvent wouldn't do them much good. On my press I have decapped primers from cases but thats probably not a recommended method. I gently push down with the decappered and they fall out and then I discard them.

barrel-nut
12-30-2011, 02:43 AM
I agree, your press is fine. I have actually crushed entire cases before, due to using the wrong die. This is surprisingly easy to do- driving the neck down into the case body. Presses have incredible leverage, and are built to take advantage of it without damage.

As to the primers, if you live in an area where you can do this without scaring the neighbors, just chamber them and fire them, with no powder or bullet, of course. Or just use the oil method.