Hi all,
Relatively new to the forums but have already benefitted greatly from the store of knowledge here!
Last weekend I did some load development at the range (thanks again @gadgetman) and had some interesting results. The aim was to find a lighter bullet/lower velocity load to give my partner's son a pleasant introduction to centrefire rifle shooting. Thanks to @257weatherby I had some different projectiles to play with.
I had researched the idea thoroughly and had decided to use AR2206H due to the ability to load to 60% of max load (look up reduced loads with H4895/AR2206H). Even if it didn't work well at lower levels it seems a good choice in my 6.5 Creedmoor for 90 to 100 grain class bullets at normal book levels.
I loaded some rounds starting at 26 grains and going up by a grain at a time to 34 grains. Overall length with 100gr Eld was 2.650 to ensure projectile was sufficiently held by the neck meaning they had a sizable jump to the lands.
26 grains showed good initial grouping and were very mellow to shoot. The fun started at 27 onwards - at least 1 of 3 in each progression did the dreaded click-boom. And then at 34 grains no more hangfires. Tried 3 more groups at 32.5, 33.5 and 34.5 as groups seemed to improve between 32 and 33. 34 grouped the same as 33 around 30mm.
After doing some more reading around the issue I think the factors contributing are likely to be:
Low neck tension (Lee collet die)
Light projectile for calibre
Long jump to lands
Relatively low case fill (though over half full)
Other relevant info:
Lapua once-fired cases
CCI 450 primer
Howa1500 rifle
Has anybody else experienced anything similar? Any thoughts on where to go from here? My thought is to go back to the book minimum and start developing from there. And go buy a 223 😀
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