Chap
If you compare the 250g with the 300, the 250s look like they are very near end of life and ready to break apart, the 300 look together and have done their business perfectly.
Back to Semisane's 250 Expanded Gold Dot....
I would really like to disagree with your statement....
I do not believe that 250's are over-expanded and near the end of their life. The 250 is constructed differently than the 300. If you look at a 250 you wil notice it has a much deeper HP than the 300. In fact if you look at Semisane's pictures again - look carefully at the right hand picture you can see the copper dot - about 1:00 off center. When the 250 expands to fully open it does not have the length of body as the 300 does (it does not have the body length in the first place. It really looks to me likeit expanded out just about right... the petals migh be laid back a little bit more that normal but still way over .75" and I would bet the bullet still has 85/90% of it weight.
This looks pretty good but not perfect, anperfect performing terminalbullet is completely expanded at the head and the long shank of the bullet is intact,
And I guess as long as I am disagreeing - I should say i disagree here also. UC's lead bullet looks really great to me of even the one Cdad posted of a 460 BS. All lead (soft lead) do not and are not designed to expand the way modern hunting bullets do. The fact is his or both conicals expanded near perfectly for a lead bullet. Pan-caking of the frontal portion of the lead bullet is normal and depending on length or weight the remaining shank looks really good. Again if you weight either one of those bullets I would bet they are over 90%
Just my thoughts and goodness I am no expert...
Here is a picture of expanded Speers and you see the same process. The 300 has more rear mass weight than the 250 does non-the-less they expanded to their max - both far from the end of their lives - neither of the two were the petals even close to coming off.