Breechplug
I have heard that BlackHorn 209 is all of the above. Has anyone used it?
Yes and the answer is most probably yes - it is probably the best but it has limits... not all ML's can use - it is to darn expensive, unless you are just hunting, and it is a little tough on BP fouling
I am totally biased - I like to shoot and one of the reasons that I shoot ML's is that is less expensive than a centerfire - moving to BH would really up the cost of shooting. I am not a continuous shooter as some others are but I shoot 5-7 lbs of T7 each year. T7 works well for me... and if MX works out it will be that much better....
Just my little bit of Bias...