Age old 223 vs 556 question

R

Rock Knocker

Active member
The only 223 ammo I've shot for years has only been handloads, and I usually load them pretty warm even my cheap plinking stuff.

Few weeks ago I gave my buddy a few of my handloads to see how they would do in his gun and he gave my some of his cheap 556 stuff, green tips and one other type I forget now.

Those cheap 556 rounds seemed to really pack a wallop compared to my handloads, granted, we're comparing my 50gr SP to the 65gr or whatever greentips.

I was just curious about the pressures of each round, I load my 50gr SP with CCI400 primers and H335 and they are loaded just to where the primers are starting to flatten out. When I checked out the 556 cases after firing the primers were still as round as they day they were made. And both 556 and my handloads were LC brass.

So this is as much a primer question as it is a 223 vs 556 question... If I switch primers can I turn up the heat of my handloads without flattening primers as quick? Or is the persieved increase in power purely because of the slightly heavier bullets?
 
If I switch primers can I turn up the heat of my handloads without flattening primers as quick? Or is the persieved increase in power purely because of the slightly heavier bullets?
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Probably yes by switching to a harder primer and also a yes to the perceived power increase of the heavier and type of bullet used in the green tips.
 
CCI 400 primers have a thin cup and are designed for 22 Hornet, 218 Bee, pressures. You need to switch to CCI 450, Rem 7 1/2, Fed 205 primers.
 
Originally Posted By: ninehorsesCCI 400 primers have a thin cup and are designed for 22 Hornet, 218 Bee, pressures. You need to switch to CCI 450, Rem 7 1/2, Fed 205 primers.

aside from my first hand expierence with them, cci says NOTHING about not using them in the 223 or the ar platform in general. If there was a problem they'd have a note to go with them saying "no no you naughty reloader"

http://www.cci-ammunition.com/products/primers/primer_chart.htm
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you dont *need* to switch to a hard cup primer. cci 400's are perfectly safe in a 223/5.56 - even in an AR. you'll get light dimpling on chambering due to the floating pin - and if you chamber a round enough times you risk a slam fire occurring (but almost any primer is at risk of that, chambered enough times under a floating firing pin) - but there's lots of folks out there who run them with nary an issue.

i run them right up to max charges with h335 and cfe223 and dont see any issues from them.

my 16" carbine gas bushmaster barrel tends to show pressure signs with them earlier than my WOA rifle gas barrel does, but not by much - and that probably has more to do with the quality of the chamber cuts as much as it has to do with the primer itself.

sure the 0.005" thicker cup on the 450's and 7½'s will withstand a bit more than the 400's will, but that cup thickness is more about preventing slam fires or primer piercings if you happen to get a pressure spike.


i've run thousands of cci 400's in multiple calibers, with loads ranging from mild to max or even a bit above published max's. the only real flaw i can find is that they dont ignite ball powder as consistently in cold weather as their hotter cousins do. I still use them as my go-to ar-platform plinking primer, but i've switched over to the 7½ for my hunting loads to help minimize velocity loss in the cold months of deer season on my ball powder loads.



i have personally shot factory ammo that flattened primers and craters like crazy, along with both extractor and ejector swipes on the case heads. when i sent pics of the fired brass to hornady they requested i send all of what i had in for testing - every bit of it specd right on the factory loaded PSI numbers. Come to find out in that instance - my gun was SEVERELY overgassed. as such the lock time on the bolt was way out of spec and trying to move well before the cases had shrunk off the case well and the pressure had dropped. As the bolt started moving, the primers were flowing into the bolt face, cratering around the firing pin hole and flattening out the primers because they had room to grow then. Once i corrected the overgassing, similar (different lot #, but otherwise identical) factory loads showed significantly reduced signs of pressure.
 
Originally Posted By: ninehorsesCCI 400 primers have a thin cup and are designed for 22 Hornet, 218 Bee, pressures. You need to switch to CCI 450, Rem 7 1/2, Fed 205 primers.

lol.gif

where did you come up with that?
 
Originally Posted By: SlickerThanSnotOriginally Posted By: ninehorsesCCI 400 primers have a thin cup and are designed for 22 Hornet, 218 Bee, pressures. You need to switch to CCI 450, Rem 7 1/2, Fed 205 primers.

lol.gif

where did you come up with that?



I was wondering the same thing. I have been using the CCI 400's in all my SR guns for over 40 years and this was the first time I ever heard someone make that claim.
 
Thanks for the help. I've gone through plenty of the 400's, bought 1000 primed LC brass with 400's and have gone through another brick of them also. I never had a problem with them except in extreme cold hunting conditions (-10 and below) I figured it was the temp sensative H335 powder that was causing the extra light shots.

Any one care to give a WAG on what my chamber pressures would be if my 400s are just flattening compared to the chamber pressures of the 556 stuff?

I've got a hog hunting trip this winter and I'm just trying to figure out if I can get a little more juice out of my AR by playing with powders and primers.
 
Don't worry about the 556 loads. Pick a load and work up to however "safe/warm" you care to be. Keep your shooting glasses on and don't be passing out "warm ammo " for you buddies.
 
That's what I'm asking about, my first "safe/warm" indicator are my primers... So what are they doing different in the 556 stuff that gives it around a 50% increase in recoil but maintain sound primers and intact firearms?

Just don't get hurt trying to understand the question
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Originally Posted By: RustydustOriginally Posted By: SlickerThanSnotOriginally Posted By: ninehorsesCCI 400 primers have a thin cup and are designed for 22 Hornet, 218 Bee, pressures. You need to switch to CCI 450, Rem 7 1/2, Fed 205 primers.

lol.gif

where did you come up with that?





I was wondering the same thing. I have been using the CCI 400's in all my SR guns for over 40 years and this was the first time I ever heard someone make that claim.

there's an old article from James Calhoun out there dating back to '95 discussing the subject of primers, pressure, cup thickness, etc over on accurate shooter & his site that gives that information.

http://www.accurateshooter.com/technical-articles/primers-and-pressure-analysis/
http://www.jamescalhoon.com/primers_and_pressure.php




as i noted above - if there was a problem using them at full pressure loads in a 223/556, the lawyers over at cci would have a *, ^, + or something telling us using them in said application is naughty.



i couldn't tell you how many i've used to date, but i'm north of the 7 year mark as a reloader and i've shot enough handloads thru my first 223 upper with cci 400's to necessitate needing new gas rings on its bolt and my blackout has consumed several thousand of them too. i may not have crossed the 10k mark yet, but if i havent, im not far off. it was the first primer i ever used and i've yet to pierce one, or even blow one out of a primer pocket. but then again i dont color outside the lines very often
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Part of my original post...
Originally Posted By: Rock Knocker Or is the persieved increase in power purely because of the slightly heavier bullets?

Originally Posted By: Tim Neitzke A quick note... More bullet weight = more bearing surface = more recoil.

Maybe you should start from the top of this thread. Better yet, leave. You've responded with a useless condescending comment to most questions I've ever asked.
 
Let's see, OP states he loads warm loads with ball powder.
Someone puts up a chart where CCI recomends 450's with ball powder.
The James Calhoon links are posted that prove my post.

I think I'll just stop here.
 
Originally Posted By: Rock KnockerPart of my original post...
Originally Posted By: Rock Knocker Or is the persieved increase in power purely because of the slightly heavier bullets?

Originally Posted By: Tim Neitzke A quick note... More bullet weight = more bearing surface = more recoil.

Maybe you should start from the top of this thread. Better yet, leave. You've responded with a useless condescending comment to most questions I've ever asked.

That's too bad, you don't even know when your being helped.
Don't break to many dishes...
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Originally Posted By: ninehorsesLet's see, OP states he loads warm loads with ball powder.
Someone puts up a chart where CCI recomends 450's with ball powder.
The James Calhoon links are posted that prove my post.

I think I'll just stop here.

I checked the local shop and they didn't have any magnum small rifle primers. I'm going to try them out soon as I get my hands on some, I just gave my buddy my last 60-70 Rem 7 1/2 for his 454. All I've got around now are 400's and BR4's.

Heck, maybe the BR4's are the reason I was getting honest one foot groups at 100 yards testing 53 vmaxs with CFE223.
 
as i understand it.... the BR4 are just a small rifle primer with the same cup thickness as the cci 450 - they're just QC'ed to a different (higher) standard to ensure lot to lot and primer to primer consistency that the benchrest crowd would demand.


[edit] i've never used them so i have no real world experience with them. as i stated earlier, for the most part i use cci 400's for almost everything that needs a small rifle primer.





 
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Originally Posted By: lyotehunternot a good idea to shoot your custom ammo in some one else's gun they are all to different.

Yeah, I gave him a full disclaimer, he loaded it up and shot it himself. He's an ex Marine that's seen much worse than warm 223 rounds. And even in my gun the primers were just barely flattening, no head swipes or ejector marks, I really wasn't worried. I checked the brass on the first one he fired and it looked just like it came out of my gun. My little 50gr SP load is so nice to shoot and accurate that he wanted to trade ammo with me.
 
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