Casting for the 41...
Well I don't know how many of you are casting your own, other than the few that mentioned it. Me personally I have purchased a few molds in the last couple of years and several more in the last year.
I have to say that I am simply blown away by the MP molds in this caliber. I picked up one of his first which was designed as close to the original Keith SWC as the folks could get it. The same mold will cast both solids and HP versions. The solid drops around 220grs from COWW and the HP runs around 215'ish depending on the alloy.
This past year there were a couple of other group buys that came to pass on MP molds as well. One was the 412-640, which is the smaller caliber almost duplicate of the Lyman 429-640 HP. There have been several calibers of this 640 type mold made and they have all been awesome. The other one is the 413-640 which drops around a 200gr solid, a 185gr HP with one pin and a 175'ish grain HP with another pin.
To be honest I didn't have a clue as to how any of the "lite" ones were going to shoot. I had tried the heavy 220gr version once tumbled in 45-45-10, and it was a dismal failure leading the barrel up completely after only 4 shots. The next testing was done with a range of loads using AA-9, and half were powder coated and the other half were lubed with Carnuba Red. The same alloy was used as was initially, but this time everything went right. I shot each set of loads from 14grs up to 16grs, of both powder coated and traditional lubed with not even a hint of leading.
Two weekends ago, I loaded up another batch, only this time I had some of the heavies loaded over 18grs of 296, and some of the "lite" ones loaded over several charges of different powders. One was 23.5grs of 296 under both the 175 and 185gr HP's. I did the same as before with half powder coated and half using Carnuba Red. I also loaded up some over some incremental charges of 2400 and AA-7. As before, after running them all through, nothing but a shiny barrel and a big hole in my bucket lid.
I guess what I am getting at here is, if your looking for a great versatile mold to save up for, or if you have the cash and one might still be available, pick a weight and check with MP molds or watch for a group buy on either of these over on Castboolits. Might as well go all out and get the 4 cavity with all pins while your at it. This will give you the option of pouring up to 3 different bullets from the same mold.
The alloy I am using is running in the 9.5-12 BHN range depending on how things come out, but the expansion is usually wonderful. It might take a little playing with the mix but something of a 60-40 blend of COWW and pure with a little tin thrown in for good measure should come out pretty close. This would give rapid expansion without being overly brittle.
Anyway, just thought I would post a little update on my progress. I haven't completely replaced the old discontinued Remington 170gr SJHP I loved so much, but to be honest, I think the ones I am casting will probably do as good a job and maybe even better. I will however fully admit up front, the top end loaded 175 and 185'ish grain ones, did pretty much turn fully inside out and loose the outer ring when I shot them into my sand bucket trap. I'm still not sure as to how well they will do on a feral hog or coyote, but I am VERY anxious to find out. Nothing like on the hoof ballistic testing, with the side benefit of being able to BBQ the good parts.