Aaron
posted this
23 August 2025
As promised, here is the information regarding the MP Mold hollow point bullet. The mold in fact, arrived on the 3rd business day from Slovenia. The brass arrived 2 days after that. America. Gotta love it.
I fired up the mold after de-greasing it and rubbing pencil lead on the hollow point spuds. Darn thing cast usable bullets on the second filling. I was off to the races!
I seated some gas checks, sized them, and squeezed in some White's Lube 50/50. I sized the bullets from .312 to .309 in the RCBS Lubrasizer. Then after prepping some new Starline brass, I filled the cases with 33gr of LEVERovlution powder. The bullets were seated to an O.A.L. of 2.518" and a crimp was applied with a Lee Factory Crimp die at the crimp groove on the bullet.
With 12 of these made up, I was ready for the chronograph and the test firing with a slightly lighter bullet at 150gr rather than 170gr I normally loaded these with.
It's important to note that the purchase of the mold and the entire test scenario and evaluation was based on firing these in a Miroku Winchester Model 94, twenty inch barreled rifle. As an afterthought upon completing the loading of the 12 cartridges, I figured I had better ensure they would chamber in the M94 rifle. I opened the action and slipped one into the chamber and DANG, the cartridge would not seat. Not off by a little, but off by about a quarter inch. No go. No joy. Ain't gonna happen. I spewed forth some choice words and began the shorter seating test to determine how deep the bullet would need to be seated before they would chamber in the M94, the Miroku M94.
I finally got one to chamber in the Miroku M94 with a O.A.L. of 2.359" rather then the original 2.518" cartridge. That's a .160" difference and the shorter cartridges look like the bullet is seated to the primer. It isn't of course but that's a lot more bullet way down in that case. The base of the bullet thus seated is halfway down the shoulder of the case. Very low, at least to my eye.
Then....a brain fart. Will the longer seated bullets chamber in a pre-64 Winchester? Son of a gun, they will. Will they chamber in a T/C Contender barrel? Answer is yes they will. With ease.
I would say the situation had been solved BUT when attempting to run either the longer cartridge or the shorter cartridge through the action, they simply would not cycle. They either jammed up under the lifter or crashed into the breech face at 5 o'clock jamming up the works. Very very frustrating if I must say so.
I am a bit frustrated that such a nice looking bullet is giving me such a fit. The Lee 170gr bullet has a nose of .300" and chambers in everything with ease. They cycle in every Winchester I have. The MP Mold bullet has a nose diameter of .3085" and won't chamber in the Japanese M94 with a tighter throat. I will buff one of these bullets down and determine what diameter the nose needs to be to chamber in that rifle.
It's great to know these will fit into the T/C Contender with ease. The 33gr charge is a bit of overkill with a 14" tube however. I will not get a very efficient burn with LEVERevolution powder in that tube. IMR-3031 was what I had been using in that barrel.
So...my evaluation of that HP bullet is on hold. It just doesn't seem to be a good design for the lever action rifles where the cartridges will not cycle reliably through the action. I'll probably reserve them for the T/C which I do hunt with regularly. I'll have to work up a different load of course, but that should be a snap.
DANG.
With rifle in hand, I confidently go forth into the darkness.
