Sheriff,
I agree with you there, I think the 243 is hard on barrels. I don't have a 243 Handi but do in a commercial mauser with a light weight sporter barrel. Don't make any diff what kind of powder or bullets you shoot after about 5 shots you can hardly hold your hand on the barrel. I had it out at the range today and shot a 3 shot group with 68 grn Berger moly HP and 46.5 grn H-414 that I have not measured yet but I tell ya it is small. I didn't have the nerve to shoot the other two rounds, just knew it would open up. Anyway, what I really wanted to say here was along the lines of what you proposed. I have always thought the 243 had much too short of a neck. What if you chambered a 243 short, say about , well that won't work. The thought I had is to make a short 243. Push the shoulder back about 1/4" or so, make it 40 degrees and have a long neck. So that the powder capacity is about 35-36 grains. The 6mmBR only has about 32 grns powder capacity if I remember correctly. (Very dangerous thing, my memory). Anyway you see what I mean. Shorten the 243 to give it a long neck and maybe freebore the chamber so that 105 grn bullets would have to line up in the freebore before contacting the lands. Make the freebore about 0.001" larger than the bullet dia. Maybe I been thinkin too much. What are your thoughts on this. Bye the bye, I had my 223 Handi UV with me also and was trying some bedding things and whatnot. Nothing spectacular so far. It will shoot 1" all day but I am trying to get it down to 1/4". Might not make it but that is where I have so much fun. The da-n wind was blowing ever which way and did not help much.