Military 223 brass question

[mookiie]

I have been told that the rule of thumb is to use a charge of -2 grains of powder as compared to a commercial piece of brass due to the military brass having thicker walls. My question is, is this a flat calculation or does anyone adjust it? Example.

Let's say I load 40 grains of powder for my 30-06 reloads, if it is military brass I would use 38 grains of powder.

So now back to the 223, let's say my regular load is 23.5 grains of powder for 223 commercial brass, would I load military brass with 21.5 grains?

Or since a 223 case is much smaller than a 30-06 would you compensate the -2 grains to accommodate for the smaller case? So in the example above would look like the below:

So now back to the 223, let's say my regular load is 23.5 grains of powder for 223 commercial brass, would I load military brass with 22.5 grains?


Does this make sense? Thanks

 

[rcmodel]

The Rule is for GI 30-06 & 7.62 NATO brass.
The Rule doesn't apply to well to 5.56 NATO brass.

I have LC GI brass that is lighter then new commercial Remington brass.
It weighs nearly the same as Win commercial brass.

See the brass weight chart about 1/4 down on this page.

http://www.6mmbr.com/223rem.html

I size, trim, and weigh it then compare it to what else I have.
If it is much heavier, it might need reducing.

But since I don't reload .223 to near 5.56 MAX pressure anyway, I don't.

rc

 

[denton]

It's true that milsurp 30-06 and 308 cases are thicker, and therefore hold less powder than most commercial cases.

This is NOT true of military 5.56 cases. Lake City cases have higher capacity than most commercial cases.

 

[kingmt]

Check the volume of the two cases. I bet you didn't find a difference.

Put it out of your mind now & go back to the way you was doing it.

 

[mookiie]

Ok great guys thanks to all!

 

[MEHavey]

While changing components is always a time to reflect on how close you are to MAX, don't just take-it-on-faith
that military brass (especially 223/5.56) is thicker/weighs more than commercial. That old saw is now more often
wrong than not.

Instead, weigh an average of the internal water-weight volumes of the brass you are switching from/to and go from there.

 

[elwoodm]

i load .223 all different headstamps and have seen enough change in volume from one make to the other that i thought my powder measure was off. but it didnt change velocity much with this round. you dont need to be worried much just dont forget about the primer crimp on the military stuff.

 

[mookiie]

Yes - I hate that military crimp. I have the RCBS case mate and it still takes forever to remove the crimp and I still have two hundred shells I have to shave it off on left.

 

[mookiie]

+1 RC that site has great info on the 223. The chart on case weight Vs water capacity is the exact data I was looking for.

 

[Walkalong]

For my plinking ammo in ,223 I use a powder charge that is safe in the heaviest brass I will be using.

For the occasional extra thick/heavy case where the powder comes way up in the neck vs the other cases, I just scrap it.