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6mm BR and H4350???

Ok, went to the range and did a crono on the 2 following loads:

32.5 gr = 2752 FPS AVG (Dec 27)
33.0 gr = 2804 FPS AVG. (Dec 27)

H4350 33.2 grs, Berger 108 = 2827 FPS avg
H4350 33.5 grs, Berger 108 = 2831 FPS avg

I was surprised that the 33.5 grs did not give the increase I expected.

I had to tap the cases with a small screwdriver after the powder has poured in the case to get the powder to settle. I think the 33.5 was a compressed load.

Don't know if the compressed load caused the small increase if FPS or maybe I am not burning the powder completely before it leaves the muzzle. It is a 26 inch barrel.

Any thoughts??
It would be fun to see what GRT or Quickload predicts regarding % burn.
 
I ran GRT for my combo and got the following for Berger 105s and 107 SMKs. Some of the data matched, some was off from reality. N555 was the other powder that gave below 100% combustion, but improving with increased weight. I've got some Berger 109 LRH coming to play with.
 

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