Finally the day arrived for me to try out my OCW loaded selection, a full 9 months or so after I prepped them!!
Anyway, I set up my targets and got the gun ready (CZ550 Varmint in .308, harris bipod, Bladetech soft cheek cushion, Burris XTR 312 zero’d for Norma Jaktmatch 155gr rounds). All my rounds were Norma cases, AMAX 155gr bullets, and Fiocchi rifle primers. Target was 100m away, cool day, still, damp.
Using a max load of 42gr dead, I had 3 sighting rounds between 37 and 39 grs , then 3 more at 40.3, 40.7, 41.2, 41.6, 42 and 42.4. I started getting flattened primers from 41.2gr, and I out this down to primer brand, but when the one and only shot at 42.4gr was a bit tighter on extraction, I decided that I would not shoot any more of those and so my max full 3-shot batch was the 42gr load.
I did not record velocities.
I followed the OCW shooting system, cleaning my barrel every 6 or so shots and letting it cool for about 2 minutes between shots.
I opted for prone because I wanted as little of my bad shooting to affect the results. I am a little recoil shy with .308 and I expected it to be worse, but I actually found this position very comfortable.
Attached is a picture of the two targets used. For me there are 3 loads that show the most promise. 40.3gr. Here the three holes are touching: an absolute first for me!
The next group is #3 with 41.2gr. This group is actually spread out but that is because I made a mistake on my point of aim second time around. By comparing aim and impact points for all three, I can see that, had I aimed at the same spot, that second shot would have been in the middle of the first and third: all touching again. My last finalist is 42gr. Two touching one just off by under an inch.
All were shooting way above the POI for the Norma Jaktmatch. 5.5” high for the 42gr load, for example.
So now I will make up some more of those three loads but with differing OALs.
So far so good!!
In truth, I am really happy with today’s outcome. It shows that, between me, and my CZ550, we are capable of just under MOA accuracy, at 100m at least. In any case that is a lot better than before!!