Ruptured Primers HELP!

[Ruraloader]

My scale is an Ohaus triple beam. Pretty solid. As a quick check I weighed some Hornady 168gr A-max projectiles.

1 of them balanced at 168 gr
2 of them balanced at 336.1 gr (168.05 gr each)
3 of them balanced at 504.2 gr (168.07 gr each)

I know that's not terribly thorough, but I don't have another grain scale handy to check against. I suppose I could take mine to work and compare it against one of our laboratory scales.

[Ruraloader]

Here's an update, in case anybody is still listening:

I recreated the same load that resulted in a failed primer, with 1 difference: I switched from Winchester Large Primers over to some CCI No. 200 primers.

My Lyman manual listed the following load data:
-168gr Jacketed HPBT
-3.300" OAL
-IMR-4895. Starting at 43.0gr for 2,444fps. Max load 48.5gr for 2,762fps.

I loaded the following rounds using Remington brass, trimmed to 2.484" and primed 0.010" below flush using an RCBS hand priming tool. My OAL was 3.300"
-4 each @ 43.0gr. Velocity averaged ~2360fps
-4 each @ 44.0gr. Velocity averaged ~2370fps
-4 each @ 45.0gr. Velocity averaged ~2455fps
-4 each @ 46.0gr. Velocity averaged ~2520fps
-4 each @ 47.0gr. No velocity data. Battery died in chronograph.

All the rounds fired very well with the closest grouping (46.0gr) being a 3 shot group of about 1" spread at 100 yards. In fact, the first two shots nearly overlapped. Not one single primer backed out or looked excessively flat.

Bottom line - I think this experiment is relatively conclusive is showing that faulty Winchester primers caused this problem.

[flyguy958]

Primers backing out is not a symptom of defective primers. Ruptured primers could be defective primers. My 2 Cents.