Hi Bob, I don't really know, hazarding a guess I'd say 15-18 as a single flat layer of 223's, and say 14-16 of 243 or 6.5mm, I never looked to see what the Hertz were on the lydl, probably 42,000, the bigger one like mine is 47,000, if given the choice I'd go for the bigger one like mine, hope this helps, ATB....Pat....PS, if I don't catch you before hand, have a good Christmas and a Happy new Year to you and your good lady.