SAECO #645 First loads

[Brettitt41]

Well I finally got a break in the weather to try my new mold a Saeco #645. My loads were 72gn OE 1.5 in twice fired Starline brass, not resized, .60 fiberwad compressed with a.45 compression die about 1/8". Tried 2 different alloys. COWW (10rnds) and Rotometals 20:1 (10rnds). The 20:1 was definitely the consistency winner on the targets. These were unsized out of the mold and SPG pan lubed, not quite round but big side was .460 low side .458. Mine dropped fairly consistently around 490gn with my alloy at 700. I was shooting the SR-1 target at 100 and got good groups 2" or so but with the 20:1 it was all vertical dispersion on both targets, 5 shots each with a bore pig pushed through after every shot. The COWW all held the 9&10 ring but were scattered, which could as well have been the shooter. Didn't get any target pics as when I was cleaning up knocked the container holding my bore pigs over and soaked the targets. Brent's bore pigs are awesome. What can I do about the vertical stringing? More crimp, less crimp, more powder compression, less powder compression. I could try some .30 wads which would be less compression. It was at least a great day to be out and fun was had.

[Don McDowell]

Probably could use more compression. .3 or more isn't out of line with OE.

[Gunlaker]

I would seriously consider no crimp at all. More compression will probably work better like Don says.

Chris.

[Lead pot]

Verticals is a sign of loss compression behind the bullet and bullet release from the case mouth.
Also barrel harmonics with different barrel rest locations on sticks or sand bags with uneven down pressure holding the rifle.
With softer alloys the obturation is more intense against the case mouth walls and if there are variances like rough edges (peened) or crimped, rolled or tapered, with uneven case lengths will effect the verticals.
Work on case prep( this includes inside volume ) and wad stacks.

[Don McDowell]

Fouling control, or lack of, can be a major cause in vertical as well.

[Brettitt41]

OK I'll work on my cases. I'll measure length again and bring them all down to a consistent size. I don't think I put any crimp on these but I might have as some of them would rise back out of the case from air pressure and I couldn't get them to stay seated. So I think I did turn my seating die down some so it just touched the case mouth enough to hold them down. Now for more compression of the powder. Is it correct to think that I should either add more powder to gain more compression or add more wads?

[Don McDowell]

More powder probably best.