Greetings,

I am reloading 5.56 brass for CMP high power rifle. We fire at 200, 300, and 600 yards. Do I need to use all the same brass? I have 750 rounds made, with LC brass, but I ran out of LC brass. All I have left is 500 pieces of FC and 500 pieces of PMC. Is the different brass going to make any difference?

yes it will make a difference.  always try to use the same brass.  The LC brass ammo will have higher pressure and there for higher velocity than the commercial brass.

Yes, it will make a difference. Are you loading for the season? Are all of the LC headstamps the same year?

All my headstamps are different years. I'm just loading to have match grade ammo at half
The cost of commercial ammo.

Few options if you want to load match grade. They may be more, but this is my list.

-Buy new quality brass

-Match headstamps of fired brass, weigh them for consistency

-buy match ammo, shoot it, reload the match brass.

I think measuring weight is done to indicate internal volume?

I segregate military brass (Lake City and WCC) from civilian brass.

.mil brass for 200 and 300, civilian brass for 600.

Weighing brass and segregating by year is a waste of time.  I process and load in bulk.

First segregation is military in one pile, civ in another.  Then segregate the military crimped from already-processed (swaged) primer pockets.

Tumble in corn to get off range grit (dirt, mud, sand, etc.).  Check for thinning and impending case head separations.  Lube, de-cap, and size (I do minimum headspacing -- maybe .002, to get minimum stretching).  Tumble in corn media again to take off the lube.  Swage once-fired military pockets.

Wet tumble for bling and clean primer pockets, then dry.  Trim on a Giraud.

Hand-prime to feel for loose pockets.  Charge cases, insert bullet, seat, box, and label.

Go out and shoot.

Thank you again for the information!

Is WCC brass basically the same as LC brass? Is the internal volume the same, and what about "FC"? I have some brass marked FC as well. I appreciate your advice. I just made 400 rounds of ammo with PMC brass. I also made 750 rounds with LC brass in November. I got my elevation dope using the LC brass so that's what I'll use in competition. Maybe I'll use the civilian brass for the short line (200 yds) or for practice.