Post by ivan on Sept 24, 2023 19:24:56 GMT -5
Love my Howa Mini in 762x39 so much I bought a second Howa Mini in 223 (20" barrel, threaded, 1-8 twist).
But this one is being persnickety about ammo. So I need to borrow y'alls brain cells and get some thoughts and input from ya....
Factory ammo - PMC 55 and 62gr FMJ, various American Eagle, some Privi "Match" ammo (well, it does have 69gr boolits and ), etc. and all give me 2-3 MOA. Factory has "1moa guaranteed with premium factory ammo"...
Soo off to the reloads. The dirt cheap recipe I use that my Savage bolt gun (1-9 twist) gives me near 1/2moa with gave 2moa or so with the Howa. Same with some of the RMR 69gr boolits that are supposed to be equal to the SMK. The one thing that gave me a ray of hope is the 60gr TMK the Savage likes (same powder charge etc as the 62gr FMJ load, quite convenient) which gave me about 1.5 moa
"Hrm.... maybe this one likes lighter bullets even though it has enough twist for 70+ grains"
So... I bum some 55gr pills from a buddy - Dogtown 55gr spitzer soft points. Published load data for my powder (BL-C2) is 25.0 to 27.0gr with the Speer 55gr spitzer soft point, so that is the load data I'm based on. Data for a non-spitzer 55gr softpoint is 25.5 to 27.5 ... and I'm unsure of profile differences between the two bullets, etc. so I don't wanna go above the 27.0 (I don't think....)
It looks to me like 24.8gr is on the edge of a node and headed bigger as powder charge goes up - which is evidenced by the 25.5 and 26.1 groups, but then 26.6 looks like it is headed back down....
I'm more concerned with accuracy than getting max velocity. Think it will be worth it to check 26.8 or .9 and monitor close for signs of pressure, but I think I'm also going to check 24.0 and 24.4, and depending on how that pans out maybe 23.8, 24.2 and 24.6
24.8gr (where my measure landed) -
25.5
26.1
26.6