300 blk

[Harter]

X39 is all I dabbled in . I did run a 200 gr paper patch over IMR 4350 1600 fps at mag length and 1700 single fed .

I don't remember what I had under the 155s , probably H322 or Reloader 10x . Having used them both in 223 62s and 6.8 with 120 jacketed up to 140 cast either should work well with 110-150 gr in the 300 .
4198 will walk a line at the edge of too slow and just just barely enough/not quite enough to cycle it will probably give the best/highest velocity though .
I've been pleasantly surprised by H322 in a pretty wide selection of cartridges with good results.

H110/296 was developed in parallel with and for the 30 carb . You'll want the mag/GI primer and a moderate crimp if you use this one .

[mater]

Thanks Harter
Been tinkering a little and found mag/mil primer are a must with the H110 as stated for top end loads. This piece of mine seems to like faster loads as the groups tighten the fastener I go, 18 gr H 110 is very nice under 125 gr SST from Hornady. The converted brass I got from Wes seems to be his usual quality 😁 so less work for me.
I chose Accurate 1680 to experiment with and have been pleased with its softer shooting qualities, but still chasing h110 ‘s groups as I’m running out of room in the case🫤. Trying 21.5 tomorrow.