The Korean .30-06 has much in common with the little girl who had a little curl right in the middle of her forehead.
An easier way to remember is the stuff in 20-rd boxes is noncorrosive (PS) and the stuff in the Garand clips is corrosive (KA).
Wide variation and some problems in the stuff imported into the US stem from manufacturing variances and poor storage in some lot numbers. Over on Jouster.com they solicited feedback from all users of Korean .30-06 and compiled a list of lots and the problems they did or didn't experience. That list saved me from buying a rather bad lot of PS that regularly pierced primers. Latest version I have is posted below:
THE LIST...PS Korean ammo by lot number...
Posted By: Denver Dick (Wayne H.) <Send E-Mail>
Date: Friday, 4 March 2005, at 9:05 p.m.
It's time for the latest updated list. Remember, this is not based on scientific testing or data. It is solely based upon postings here and BattleRifles.com. Lately, however, I've been getting e-mails with info and that's been incorporated too. If there is nothing next to the lot number, that means multiple positive reports. The others speak for themselves.
ALWAYS examine your ammo carefully before you fire it. Remember, this stuff is surplus and may have been subjected to nasty conditions.
Okay, that said...drum-roll please...here is...THE LIST:
PS 2-027 (one positive report based on unknown number of rounds fired)
PS 2-033 (BAD? - one report - unspecified problem)
PS 2-035
PS 2-083 (one positive report based on less than 200 rounds fired)
PS 2-088
PS 2-089 (one positive report based on 200 rounds fired)
PS 2-090
PS 2-093
PS 2-094
PS 2-096 (some black corrosion, otherwise positive report on very few rounds fired)
PS 2-097
PS 2-098
PS 2-100
PS 2-101
PS 2-102 (one positive report based on 200 rounds fired)
PS 2-103
PS 2-104 (two positive reports based on a few hundred rounds)
PS 2-105 (one positive report based on a few hundred rounds)
PS 2-106
PS 2-108
PS 2-122
PS 2-123 (report of one dud round out of 400 rounds fired)
PS 2-124
PS 2-127
PS 2-128
PS 2-134
PS 2-135
PS 2-138
PS 2-142
PS 2-144
PS 2-145
PS 2-146
PS 2-147
PS 2-148
PS 2-149
PS 2-151 (maybe OK - based on VERY limited information)
PS 2-152 (VERY BAD - DANGER - numerous reports of ruptured heads!)
PS 2-154 (VERY BAD - DANGER - multiple negative reports splits and ruptured head)
PS 2-155 (BAD - one report of splits 3 out of 352 rds)
PS 2-156 (BAD - multiple report of serious splits)
PS 2-157
PS 2-158 (VERY BAD - DANGER - Nasty split cases...all the way to the head of the case)
PS 2-159 (one positive report based on 400 rounds fired)
PS 2-161
PS 2-162 (one positive report based on 300 rounds fired)
PS 2-165 (maybe OK - multiple positive reports - one report of infrequent and minor gas leakage around primers...NOT blown primers)
PS 2-169
PS 2-171 (one negative report of blown primers)
PS 2-173
PS 2-174 (one positive report based on 200 rounds fired)
PS 2-177
PS 2-179
PS 2-181
PS 2-183
PS 2-184
PS 2-185 (one report of blown primer and one unspecified negative report)
PS 2-186
PS 2-187
PS 2-189 - questionable? in one box out of 40 approximately 10 rounds with a strange blue color around the head of the cartridge extending down approximately 3/8"
PS 2-192
PS 2-193 (some of this lot badly corroded, otherwise positive reports)
PS 2-194
PS 2-195
PS 2-198
PS 2-202
PS 2-204
PS 2-205