A while back a friend of mine came into a number of ammo cans full of Lake City 7.62x51 match ammunition, both M118 and M852. His elderly grandfather-in-law who used to shoot a match M1A found out my friend shot 308 and gave him the ammo. Pappy was all right!
Anyway my friend and I hit the range with three or four accurate 308's and shot 300 yard targets. We generally did very well, but now and then there would be a flyer despite no wind, a good trigger squeeze, and so on. This was with us just opening boxes and shooting. So the light bulb lit up. Runout?
I took a bunch home, opened it up, and started putting it on my Sinclair runout check fixture. There it was, major runout for a round here and there. This was particularly true for the M118 cartridges. So I segregated some batches, let my friend shoot them blind to what I was testing, and the runout did make a difference.
Another thing I did was take some cartridges that had pretty good runout and pop the asphalt sealant inside the necks by seating the bullets a little deeper using a Lee dead length seating die. These shot very well, rivaling good handloads.
A little forensic work (disassembly of sample boxes from good shooting lots) also helped me realize gnat's ass control of powder charge weights is wasted effort in a lot of situations.
I came to the conclusion Lake City had the load worked out very well, but production and assembly methods of the time left something to be desired. The fired LC cases when assembled into straight handloads shot very well. A good bit of time and a lot of shooting later those vintage LC cases were getting tired. So when new LC headstamp cases started showing up as components I got nostalgic and decided to make more of my own "LC Match" cartridges. The M852 I can dupe pretty well, but the correct bullet for the M118 would be the old 173 gr. fmj boat tail. I use 175's from Sierra, Nosler, and Berger for those so I have a bullet advantage there.
