5.56 brass in a .223 chamber

[mowmer]

I've been using LC 5.56 brass for all my reloading of that caliber including in my Remington 700 (.223 chamber). I've chronographed my reloads and know they are around 2950 fps. I'm pretty sure this is safe and I can continue to use 5.56 brass (correct?). My question is, would I get better accuracy for some reason if I used .223 brass instead (out of my Remington 700). Thanks.

 

[Walkalong]

5.56 or .223 does not matter as long as the cases are consistent. A good batch of 5.56 will outshoot a bad batch of .223 and vice versa.

 

[Remo-99]

The brass is basically the same, except some may have a lower case capacity, so loads with 5.56mm brass should be worked up as seperate batches, than commercial 223rem cases.
If your only using 5.56mm brass, just work up loads as normal.
Once the primer crimp is taken care of, on the first reloading, just load them like you would if they were 223rem, after that.

 

[Walkalong]

Some military cases are heavier than some commercial, but some are not.

 

[243winxb]

they are around 2950 fps. I'm pretty sure this is safe

fps tells you nothing about pressure.

would I get better accuracy

Good quality brass of the same lot/brand will be the most accurate. Bullets are even more important.

 

[mowmer]

fps tells you nothing about pressure.

.
When used with reloading data from a reloading book and looking up the powder amount and FPS shouldn't that give you a idea of pressure? If not how would you know your at a safe pressure.

 

[Walkalong]

fps tells you nothing about pressure

Right, or at least not much.

When used with reloading data from a reloading book and looking up the powder amount and FPS shouldn't that give you a idea of pressure?

Not necessarily. A short high pressure spike may not give you as much velocity as a lower pressure but longer burn will.

Equal velocity doesn't always equal the same pressure. That is obvious when reading some data that gives pressures.

 

[243winxb]

When used with reloading data from a reloading book and looking up the powder amount and FPS shouldn't that give you a idea of pressure?

1 inch of barrel is about maybe 35 fps. A 20 inch bbl should be slower than a 26" bbl. using the same load. If the loading data is gotten with the same length barrel as your firearm , it will help some.

If not how would you know your at a safe pressure

Get to know high pressure signs like -loose primer pockets-expanded web-shiny mark on brass head from ejector-the look of the brass as its ejected from an auto.-bolt actions, hard bolt lift-extractor ripping up the rim on autos-primer flowing into bolt face around firing pin. Some photos here > http://www.photobucket.com/joe1944usa

 

[TonyAngel]

Yes, some 5.56 brass has less capacity than some commercial brass. I have also seen some commercial brass that had less case capacity than the 5.56 brass I had on hand at the time. The moral is that some brands and lots differ in case capacity, so work up.