That is a problem here. Finding BLR's with steel receivers for sale on the used market is rare. I have seen exactly 1 aluminum receiver BLR converted to 416 Ruger. They cut the barrel off but left I think about 10" or so of the barrel on the receiver. Then they bored and threaded the original barrel, and threaded a new 416 Ruger barrel to match. The company said the jigs that had to be manufactured to machine everything true were a major undertaking. This was done by a company called Aria Ballistics Engineering. I spoke at length to the owner of this company about converting a BLR for me to 458WM. He did not say "no", but did explain what a PITA these guns are to convert. I got the idea this was going to be a VERY expensive proposition, if they accepted the job. They were relocating their shop to another state at the time, and were not taking on new work. I haven't checked back since. If I recall correctly, the 416 Ruger converted rifle was offered on GB at around $4800. Very professional work. I had no idea the barrel had been "spliced" from the detailed photos. I only knew because the owner told me.
I never trust the Lee Factory Crimp Die without a cannelure on heavy recoiling rounds.
Now that looks interesting, I had a cheaper smaller unit when I loaded 10mm slugs in my 38/40 back in the day, I think 180-200gr XTP.
Of course you are correct about the Lee dies. My father wore belt and suspenders all his life. Although I don't dress like him, I guess deep down where it counts I'm a "belt and suspenders" man too.
Pure soft lead flows into the shape of the die when swaged at about 5000 psi at room temp. The psi required for the lead to flow increases with the SQUARE of the hardness. That means for every 2 points Bhn, the psi to make the lead distort roughly doubles. 7 Bhn requires about 10,000 psi. 10 Bhn requires about 30,000 or more. 13 Bhn would require about 60,000 psi. People don't realize when you go from 5 Bhn of pure lead, to 13 Bhn of wheel weights, you are increasing "toughness" of the lead against deformation about 12x. The harder the lead gets the more prone it is to break on impact with a hard surface, but if it is inside a thick jacket, it is likely to still hold together. That is why your WW lead will knock a hole in a knot and just keep going, ESPECIALLY if jacketed. It is also why anything much harder than pure lead can crack smaller swaging dies.
