- Joined
- Dec 26, 2009
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My Dad has an older Lyman Great Plains Rifle. He has been toying around with loose Triple Seven powder. I beleive that he has gotten upto 120 grains and it seams to blowing his hammer back to full cock. I forgot to mention that it is a .54 cal. and I beleive that it has a 1:48 twist. He shoots 400 grain conicals. Is this a sign of an over charge or just a weak hammer spring?