Muchas gracias. https://app.box.com/shared/static/rdic4ks22d.gif
....
Printable View
Muchas gracias. https://app.box.com/shared/static/rdic4ks22d.gif
....
Just my 2 cents, but with the compression differance between the 2 cal. I have found that they even eject differantly. The pile if brass from the 223 is laying in a differant spot then the 556.
FYI to those using my reamer, beware the nitrided / Melonited barrel, they ream the reamer :-(
Thank you for this thread! It's amazing how much misinformation is on the web. Since this is stickied here, I assume that it's the general consensus and the most trustworthy. Also it has more evidence than many resources I've read.
I still have 1 question that wasn't explicitly proved out here; case thickness. I've read on wikipedia (yes it's not a 100% accurate resource, but it IS reviewed by many many people so I feel it carry's SOME potential for accuracy), that the wall thickness is the same and the brass is identical:
One of those sources on that statement is this and in that article it says:Quote:
there is no such thing as "5.56 brass" or ".223 brass", the differences in the cartridges lie in pressure ratings and in chamber lead length, not in the shape or thickness of the brass.
Which contradicts the statement he just made...so my question is:Quote:
Military 5.56x45 brass often, but not always, has thicker internal construction, and slightly less capacity than commercial .223 Rem brass.
1. Does the 5.56x45mm case have a thicker wall, inwards, than the .223 REM. It's clear that they have the same exterior dimensions.
2. If it does, what points of interest are there relating to reloading 5.56 cartridges with .223 dies, for a 5.56 chambered gun?
3. Is there a free online resource that describes reloading information for the 5.56x45 cartridge and preferably, alongside the .223 REM cartridge? I already have a Lyman reloading bible about 3" thick, so I'd rather not buy another. But it only has info for .223 REM
4. Would I be better off just loading my 5.56x45 cartridges at the specs of a .223 REM Cartridge? I'm just plinking with it. My logic is the overall length would be shorter than 5.56 but would be okay since my gun is a 5.56 chamber. And the pressure would be lower than both a factory 5.56 and .223 round, since I'm putting a 223 powder quantity in a 5.56 case. Which again, would be fine since I'm just plinking, or could this potentially cause issues with cycling?
5. From what I can tell, I can use all of the .223 reloading dies to reload 5.56, correct? both cartridges use the same diam bullet (0.224"). This leads to my next question:
6. if I have my station setup to load 5.56, can I use that same setup (same overall length: crimp location, and neck flaring depth) to load a .223 cartridge? SO LONG as it's fired from my 5.56 chambered AR? Or will that higher pressure in the .223 case (with the thinner walls, unless you tell me that they are indeed the same as 5.56 in that regard) cause too much stress on that case and cause it to rupture or split?
I've reloaded 308 rem, 8mm Mauser, 30-30 win, 45acp, 357 mag, 44 mag, but these AR rounds are such high pressures and are used in a more complex weapon (compared to a 308 or 8mm which are also higher pressure, but bolt action), that I want to be sure that I know as much as possible before attempting to reload for my AR.
Sorry for the long post.
You can eliminate all your concerns by following two rules.
Reload following published 223 Rem data.
Don't shoot 5.56 pressure ammo in a 223 Rem chamber.
I figured as much, but I'd still like to know whether the 556 case is thicker, just for the sake of knowing.
And if I load 5.56 cases following 223 load data, then will that pose a problem? Particularly because if it's thicker on the interior only, then that would mean there is slightly less volume inside it. For examole: If it calls for x amount of powder per 223 case, and I put it that x amount in a 556 case, which potentially had a smaller volume, then that 5.56 cartridge is going to have a higher pressure than indicated for that load in a 223 case. Whether or not that poses a problem idk. But it would be good to have all of the facts going into this.
One way to negate some of the problems is to choose a case brand to load and stick with that case.
Such as Lake City: https://www.grafs.com/catalog/product/productId/77610
Do you have an electronic scale? If so, choose a random case, weight it, set that weight as the tare weight, and then start weighing - I draw a circle around the base with a sharpie to ensure I put them in exactly the same place. You will see that there are slight variances in case weights, even within the same head stamp.
I took 10 Hornady .223 cases, the first case weight was 92.8gn. Of the remaining 9, two cases weighed the same, the remaining cases were between .3gr and 1.2gn of the first case.
I took 10 Lake City NATO stamped 5.56 cases, the first case weight was 96.1gn. Of the remaining 9, three cases weighed the same as the first case, the remaining cases were between .6 and 1.0gn of the first case.
So, apparently the LC 5.56 cases are around 3gn heavier than the Hornady cases.
Measure the volume of the cases if you feel the need. I don't know of anyone loading plinker ammo separating mil brass from commercial.
Just wasn't sure if it would create a large enough difference that it would cause the grouping to be off by a few inches at 100yds. If I shoot a mag of 556 loaded at x grains and a mag of 223 also loaded at x grains, I don't want to be noticeably off target. But, I suspect it wouldn't be that significant.