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

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

Post by Drcarren » Tue Dec 05, 2017 12:00 pm

I'm still having problems with chambering and or extracting. I've measured every single round at the neck and even with a dimension of .332" I still get failures to feed and or eject. Is it possible the barrel is not right. This is the most frustrating experience I've had with reloading.

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

Post by smustian » Tue Dec 05, 2017 12:20 pm

Drcarren wrote:I'm still having problems with chambering and or extracting. I've measured every single round at the neck and even with a dimension of .332" I still get failures to feed and or eject. Is it possible the barrel is not right. This is the most frustrating experience I've had with reloading.
Need more info. Gun specs ie: gas system, feed ramp cuts in receiver?, bullet, coal, what does it do when trying to extract and/or chamber a new round, etc

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

Post by dellet » Tue Dec 05, 2017 12:39 pm

What is the length of the loaded cartridge?

Make up a round without powder or primer.

Insert that round by hand into the chamber and see if it sticks.

Shorten the round .030" and repeat until it no longer sticks.

Also try an empty piece of brass the same way, you might not be getting the base sized correctly.
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Drcarren
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Re: STICKY - Good/Bad brass list converting 5.56->300blk

Post by Drcarren » Sat Dec 09, 2017 2:24 pm

My loads are 2.100" +- .003" , I'm using 147grn bullets. I've made dummy rounds and tried getting them to chamber. It's about a 50/50. Some times the round won't chamber all the way, other times they chamber but I have to hold the charging handle and slam the butt stock to pull the cartridge out. The gun is a 16" with a pistol length gas system M4 feed ramps. I bought the complete upper from Diamondback Firearms a few months ago. Factory ammo works fine, so I know there is something wrong with my loading or the barrel has very tight tolerances. If the barrel is a little under then using cut 223 556 brass might be a real thorn in my side. I've been trying to get the loaded rounds so that the neck measures .332" no more than .333". I make the case length 1.360" +- .003".

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

Post by dellet » Sat Dec 09, 2017 3:08 pm

It's back to what I said before.

It's either the bullet or the base. Pull the bullet from one that is hanging up and chamber just the brass.

If that does not hang up, then seat your bullet deeper or straight. I'm guessing it will still hang up.

Most likely your die is not sizing the base all the way down, or there is a remote chance you are not getting the shoulder set correct, but that is not likely.

If you want to know the diameter of the neck portion of your chamber measure a fired case from a super and add .002"
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smustian
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Re: STICKY - Good/Bad brass list converting 5.56->300blk

Post by smustian » Sat Dec 09, 2017 3:18 pm

Get a slotted Sheridan gauge for Christmas and it will show you exactly where the problem is with your reloads.

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

Post by Drcarren » Mon Dec 11, 2017 7:19 pm

I have figured out what the problem is, the bullets. My brass was fine but some of the bullets were out of round. What a friggin nightmare. No more pulled bullets for me unless I can inspect them first.
Thanks for everybody's input, I learned quite a bit from the forum so far. I look forward to more conversations.

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

Post by bradspon » Sun Jan 14, 2018 2:59 pm

Hi All,
I'm new to this forum but I have been using this forum as a resource for a few years now. I just wanted to add some info to this Good/Bad list. The GFL 223 brass that is listed as "good" on this list turned out NOT so good for me. When I load these with a bullet the neck measures out to .335". The SAAMI chamber specs lists the chamber's neck diameter as .335". when the chamber gets slightly dirty the GFL necks will get jammed and I would have to mortar the rifle in order to eject. As a rule of thumb that I use, any loaded brass that measures under .333" is workable.

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

Post by BallisticTools » Tue Mar 13, 2018 3:53 pm

bradspon wrote:Hi All,
I'm new to this forum but I have been using this forum as a resource for a few years now. I just wanted to add some info to this Good/Bad list. The GFL 223 brass that is listed as "good" on this list turned out NOT so good for me. When I load these with a bullet the neck measures out to .335". The SAAMI chamber specs lists the chamber's neck diameter as .335". when the chamber gets slightly dirty the GFL necks will get jammed and I would have to mortar the rifle in order to eject. As a rule of thumb that I use, any loaded brass that measures under .333" is workable.
GFL is one of those where they seem to be good most of the time, but there's some that aren't good. I added a note to the list that some GFL can be thicker.
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Re: STICKY - Good/Bad brass list converting 5.56->300blk

Post by Jesse Heywood » Mon Nov 26, 2018 10:42 pm

In my last batch I found one case marked AP 16 - 5.56. Arms Corporation of the Philippines
Neck thickness .012

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