Cast these 39 gr hollow point boat tails for my GK1 last night. New mold. Tried to keep the temp around low 600's.
The drive bands are large enough diameter that it requires force to push these into the chambers. I push them until they are just flush with the rear end of the magazine and they are held in place there by the chamber rifling.
Again this is my first time using these and I was worried they might be loose and able to slide forward like some slugs, but they stay put.
These seem like a good weight... gk1 should be able to shoot them at 900+ fps though i will be shooting at much lower power generally
Just shot a mag. They grouped very well (perhaps a coincidence - much tighter than i am used to on this magazine but i am shooting off hand standing at about 20 yds so who knows).
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