Like you, I've always used phone books; never had the luxury of gel. I don't shoot as much as I used to; cna't get out and about anymore, long story. You might try taking newspaper and stacking them on a long box so that you have a column several feet thick. I have used that trick a time or two also. The newsprint can also be wet by soaking or up-ending a buck of water into the box of paper. Results will vary but I'm not necessarly sold on the ballistics gel for that matter.