Couple of suggestions @flock, probably telling you how to suck eggs, but anyway... the longer bearing surface of the -X means that for a given powder load, it will generate higher pressures, sometimes too much more. The two bullets -X and -M behave very differently in most (all?) rifles and should have seperate load development. The difference in shape, but equivalent weight, is because there’s more lead / less copper (thinner jacket) in the -M. Totally different bullets.
Couple of blokes have come unstuck with putting a hot -M load under an “equivalent” -X, blown primers, stuck bolts etc. My experience of loading the two is that the 178gr -M likes a fair bit bigger push than the 178gr -X. Very effective hunting bullet.
Using frangible hunting bullets and expecting the bang flop from dumping all the energy inside... very dependant on shooting the animal in the shoulder or just forward, the old “front line of the foreleg” position. If the traditional heart shot is used, or its a wee bit high and back in the rear lungs towards the liver, expect a runner. Discussed this with @Wingman this week, photos of TMKs shot into the front of the chest cavity. Instant jellification of the lungs and all the important bits connecting to the heart, including the CNS that produces the bang flop. I used A-Max for years with that shot placement, very dependable when you don’t want even a short runner.
What I like about the ELD-X so much is that the top half breaks up and fragments in a wide radius of damage, the bottom half pushes through with dirty great big petals making a big hole. Best of both worlds.
Honestly if a typical meat deer is hit in the position described, it doesn’t really matter if its an -M or an -X, its going down. Just like @GWH’s video yesterday.
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