• Mossberg Owners is in the process of upgrading the software. Please bear with us while we transition to the new look and new upgraded software.

Chilly Chrono Day in Aubury


.50 BMG
Today I went to the rifle club in Aubury CA, and shot my .45 and .308 handloads thru the new RCBS chronograph I got for Christmas. Weather was mostly sunny and in the 50s with occasional light Breeze.
I put all the .45 chrono loads into a 10 yard target (which developed much daylight after 40 rounds) & I ONLY managed to shoot the chrono twice with the 1911.

They were just flesh wounds, and except for eating batteries at a high rate, it was ok all day. I managed to chrono 80 rounds total & by the end I was on my 3rd battery.

The .45s were all the same: Xtreeme copper plated lead 200g roundnose on 4.5 grns of Red Dot.
Average velocity of 20 rounds was 785fps. I wasn't shooting for accuracy, but just to chrono them.

The .308s were in 8 different formulas using Varget powder with 150grn Hornaday GMX projectiles, 168grn Barnes Match BTHP, and 180grn Barnes TSX Triple Shock.

Best formula of the day was Barnes 168 grn BTHP on 47 grns of Varget, 2.800" coal.
I think they would shoot better with a dash more powder and about 0.020 longer coal, but so far I'm pretty happy.

I had taken my scope off yesterday, lapped the rings and re-mounted it, so you'd suspect the POI would be all wonky but it was not so. I shot this at 50 yds thru the chrono with the weakest loads: 180 grn TSX /44.5 grns varget. I was trying to miss the chrono more than hit the target here. ;) my pattern is over 3 MOA actually, but it was OK because I was on the paper!


After the .308 chrono work, I put two more on paper at 108 yds with some weak loads (~2500fps 150 gn Hornaday gmx/ 44gn Varget.)


Then I shot 3 with about the same results. The scope was clearly still very close to the old POA, as I would normally be 4.5" high at 100.


I switched to 228 yds and placed a cold shot 6" low, on center by 1" with the last 150gn. Then I swithed to the 168gn over 47 grns Varget and. BINGO! I was dead on level, and just 2moa off center, and made a nice 1moa pattern of 5 shots right off.


Then I was out of 168 and swiched to 180 grn TSX over 45.5 grns Varget. (Those were over 100fps slower.) I put one nearly in my previous pattern with a light up-flinch. Then I adjusted POA 2 MOA left and shot the 4" pattern. I hit the bullseye with my last shot of the day. I took that as a good omen and went home.

Those 180s need more juice, but at least I'm on target at 200+ yds now.


.50 BMG
I broke out the calipers to check my Target and the large pattern is 3.72" on Center maximum while the small pattern is only 1.3" on Center maximum.

1.3" at 228 yds = .55 MOA


It looked far bigger than that to me on the splatter Target but when I measured it the truth is revealed.