I think they are just regular aluminum rivets?. I will have to see what the pack says. If you aneall the rivets will it not weaken them?
No. It'll naturally re-harden if just left to sit or will work harden during bucking. I use the torch soot method....melted a few rivets before I went to a propane torch for actual heating. They buck soooo much easier then. Good read on annealing here: http://www.tinmantec...s_continued.php
The solid rivet you want to be using is the MS20470AD, these rivets are what mfg's. use for general aircraft strucuture. They are very strong and easy to buck. The diameter is in 1/32nd's and the length is in 1/16th's, example MS20470AD3-5 is 3/32nd's diameter and 5/16th's long. The trick as previously mentioned is to use a good rivet gun and a heavy bucking bar. Take your time, practice up on some scrap (rivets are dirt cheap) to keep the smileys away. Google and read up.
I want to say I use AN470AD-6-7 rivets. Have a few different lengths for different applications. I run mine with the stick through at 1.5 times the rivet diameter. I also use a 3 pound maul as a bucking bar. It's surface is flat and works really pretty darn well. I get mine from aircraftspruce.com at what seems to be a decent price.