STICKY - Good/Bad brass list converting 5.56->300blk

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STICKY - Good/Bad brass list converting 5.56->300blk

Post by BallisticTools » Fri Apr 04, 2014 8:37 am

Originally compiled by tlee_20, updated with user reports. In general, the wall thickness around 1.360 inches from the base will determine success or failure. As a rule of thumb, if the wall thickness is greater than 0.014, there may be problems with the loaded diameter of the neck being too large to chamber easily.

Neck thickness data:

Factory Blackout brass

Gemtech (factory 300 BLK) - 0.011"
PNW Arms - 0.011"
RP - 0.010"

Converted brass

ADI - 0.012"
Aguila - 0.012"
A USA - 0.012"
FC - 0.013/0.014" [Note 1]
GFL - 0.012" (Fiocchi) Some GFL may have different thickness
HB - 0.013"
Hornady (223 headstamp) - 0.011"
Hornady (nickel 223) - 0.012"
IK03 - 0.012" [Note 4]
IMI - 0.012" [Note 4] Listed on both lists, but seems like more often good than bad.
IVI - 0.013"
IVI ('85) - 0.012" (runs great)
LC - 0.011"
LC (converted blank) - 0.012"
M193 - 0.011/0.012"
Norinco 223 - 0.010"
NOSLER - 0.012”
PERFECTA 223 rem. - 0.012"
PMC - modern "bronze" and "X-tac" are good, older PMC with small letters may have problems
PS - 0.011/0.012"
PSD - 0.011"
RA - 0.013"
RA ('69) - 0.012"
RP .223 - 0.011"
SSA - 0.012"
TAA - 0.013-0.014" [Note 4]
Tula - 0.0115"
TW 67 - 0.012”
TZZ - 0.012"
WCC - 0.010/0.011" (Some less common WCC headstamps run thicker, but the majority are good to go)
Winchester - 0.011"
WIN NT - 0.011"
WMA - 0.011" (Winchester Military, equivalent to WCC)

Thick neck wall, bad without neck turning:

AB 556 - .015" to .016"
ATI - 0.015" [Note 3]
CBC - 0.014/0.015"
CJ6 - 0.015"
CJ 8 - .014"
DNL - 0.016"
FNM - 0.016" [Note 3]
FRONTIER - 0.015"
GECO - 0.015/0.016"
Hot Shot - 0.014" [Note 3]
HRTRS ( Herters?) - 0.017"
ICC - Reported as bad
IK03 - 0.015" [Note 4]
IMI - 0.015" [Note 4]
IVI - 0.015"
KFA .223 REM - 0.015"-0.019"
L2A2 - Reported as bad
MKE13 - Anecdotally reported as troublesome
MPA - 0.015"
Norma - 0.015"
NPA - [Note 3]
PMC (old headstamp) - 0.015"
PMP - 0.015"
PPU - 0.014/0.015" [Note 3]
RAM 223 - .014"
RORG - 0.015"
RWS - 0.014-0.015"
S&B - 0.015/0.017"
SADU - 0.014/0.015”
TAA - 0.013-0.014" [Note 4]
T - 0.015
SADU 5.56 - 0.014-0.015"
Wolf Brass .223 - 0.014"

General notes:

There's no consistent difference between "5.56" and "223" when it comes to brass.

Many manufacturers may use different sources for casings at different times. This means that even within the same headstamp, it is possible that a particular batch was from a different source and may be different. Treat this list as a rule of thumb, and double check before processing a large quantity.

Note 1:
"FC" brass includes several types of brass that don't seem to come from the same factory. Most of them are good to go, but the "thin web" FC that turned up a few years back tends to have thicker walls and will cause neck thickness problems. Some FC that runs thicker is the newer stuff. Has beautiful annealing marks on it. Has FC @ 12:00, numbers @ 3:00 and/or 9:00 (May have both, could just have one), and the year @ 6:00

Note 2:
NPA is very low quality brass, with a super small flash hole, and is likely to cause broken or stuck decapping pins, or other problems.

Note 3:
The brass marked with this note may require extra sizing force, and machine flex may cause them to headspace too large if the machine is not set up specifically to do this "harder sizing" brass. This is due to thicker brass, alloy variations, or variations in factory anneal. This isn't always universal within a headstamp, for example, some older PPU had the problem and others did not.

Note 4:
This brass is included in both the good and the bad list based on differing user reports. It is important to keep in mind that sometimes a single headstamp can be made at multiple factories on multiple differing manufacturing processes. Other times a manufacturer that has their own brass factory might bring in brass from another manufacturer during times of high demand or to fulfill a large contract.
Last edited by BallisticTools on Mon Mar 02, 2020 5:55 pm, edited 25 times in total.
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Re: Good/Bad brass quick reference list - sticky please?

Post by AnotherMadHatter » Fri Apr 04, 2014 1:13 pm

KFA .223 REM - 0.015"-0.019" Sampled 10 or so of 40.

I acquired ~40 or so of this brass from a range where the guy shooting didn't reload so gave it to me. I converted it with the pile of mixed headstamp brass because for me it is all just plinking anyway. Went to shoot it, and all of the KFA .223 REM headstamped brass would not chamber. (This is before I received my headspace gage)I disassembled the ones that would not chamber and found that the neck wall thickness were 0.015 - 0.019". The LC, FC, and PMC brass I measured averaged 0.008" +0.002"

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Re: Good/Bad brass quick reference list - sticky please?

Post by RDA » Fri Apr 04, 2014 1:36 pm

Why do we now have two threads on the same topic?

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Re: Good/Bad brass quick reference list - sticky please?

Post by certifiable » Fri Apr 04, 2014 1:56 pm

RDA wrote:Why do we now have two threads on the same topic?
:lol: that's quite prevalent around here! :shock:
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If we falter and lose our freedoms, it will be because we destroyed ourselves."

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Re: Good/Bad brass quick reference list - sticky please?

Post by gabe1519 » Sun Apr 06, 2014 2:06 am

RDA wrote:Why do we now have two threads on the same topic?
As described in the OP, he is expanding on the list of good/bad cases that were discussed and buried in the original thread.

I'm interested in knowing which PMC cases are considered "old" vs. the new ones. I recently bought a batch of mostly PMC cases some with the large, medium, and small headstamps. From now on I will be purchasing only LC to cut out all the headache and worry of dealing with random cases. It seems the best place to purchase brass would be from sellers that buy directly from military auctions. If I had the time and money I would definitely apply for an end use certificate (EUC) and participate in one of those auctions.

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Re: Good/Bad brass quick reference list - sticky please?

Post by vertical ascent » Mon Apr 07, 2014 11:57 am

Anyone tried converting the Wolf brass .223 cases, did it work?
Thank you all

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Re: Good/Bad brass quick reference list - sticky please?

Post by hoser » Sat Apr 12, 2014 1:27 pm

Long story short, stick with US headstamp brass and you will be fine.

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Re: Good/Bad brass quick reference list - sticky please?

Post by farm use » Sat Apr 12, 2014 2:39 pm

IMI 5.56 brass is bad. Measures about .015" will not chamber. Just saying

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Re: Good/Bad brass quick reference list - sticky please?

Post by anotherkelley » Mon Apr 14, 2014 2:47 am

Here's another good thread.....the "good, bad, and ugly" regarding brass.


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Re: Good/Bad brass quick reference list - sticky please?

Post by randyrucker » Mon Apr 14, 2014 8:43 am

PPU gives me problems all the time. I started to just throw them away when I run across them mixed in with LC.

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