You may or may not have heard it, but Marlin microgroove rifling in barrels has a bad reputation when used in connection with cast bullets in centerfire
calibers. I've got one centerfire rifle barrel made by Marlin that has the microgroove rifling. It's a .44 Magnum chambering. I don't shoot it
very often, and mostly with jacketed bullets. Because .430 bullets are so expensive now, I decided that I wanted to cast some bullets to shoot in this rifle.
I've been thinking about this for a year or two (actually since before bullets went skyward in price), and lately along came the Lyman 4-gang Elmer Keith
.44 bullet mould.
I already had lube/sizer dies in .429 and .430. The .429 came with my Lyman 450 lube/sizer, and I doubt if I ever would've used it as it is undersize for most .44 barrels now being made.
I'd heard on the Greybeard Outdoors site that Marlin .44 barrels are oversized. Since I had a sniff that something was different about my Marlin barrel, I decided to check this out. Sure enough, when I slugged the barrel it measures .432 across the grooves and .427 across the lands.
Here is a link to the whole story:
http://www.leverguns.com/articles/fryxell/microgrove-barrels.htm
If you read through that article, you'll see that the author suggests that there isn't anything inherently wrong with shooting lead bullets in Marlin microgroove barrels, so long as you get the bullet size matched to the size of the bore.
Therein lies the problem. Nobody makes a .432 or .433 sizer/lube die as a regular item; special orders are a possibility at high cost. A lee push-through sizing die can be custom ordered for, what, $30 or thereabouts, but that commits you to use liquid alox lube that isn't necessarily compatible with the design of your cast bullet. You can always use your bullets in their as-cast size if they come out oversized to approximately what you need, but then you are going to have to pan-lube them and that's not my first choice.
The bullets cast in my Lyman 4-gang mould block drop out at .433, just about a perfect size for my .432 Marlin-made barrel. My solution for lubing these was to take my .429 lube/sizing (Lyman calls them an "H&I die") and honed it out to .4325. I did this carefully on my drill press. I took a piece of dowel slightly over 3/8 inch, cut a kerf in one end, and inserted a small strip of Emery cloth which I wrapped around the dowel. Carefully, I honed out the H&I die making sure to rotate it around while honing to ensure uniform concentricity (as much as I could Mickey-Mousing it around such as I was). I used cast bullets to check it for size periodically while honing, and after not too long, I got it down to .4325. I made a quick pass with some fine sandpaper to finish it off .
Basically, the idea in this case is to use the H&I die for lubing only. I want the bullet in its as-cast size, but want to use the H&I die to perform the lubing process.
Part of the H&I die set is the metal rod that goes in the cylinder. The bullet sits on this rod (or round) inside the actual die while it is being sized and lubed and this metal rod is exactly sized to fit closely without friction inside the die. When you hone out the die, the bore size is greater than it ought to be in relation to the metal rod that fits inside it. The extra clearance between the die and the rod allows some sizing lube to leak out into the area underneath the bullet. When this happens, as you lube bullets you have to clean this out every pass or two, which is a pain in the neck. The H&I die has rows of holes along the sides to allow the sizing lube to flow into the lube groove on the bullet. Since my .44 bullets only have one groove, I only needed two whole open on the sides of the die, opposite each other spaced at 180 degrees. These holes are 1/8 inch diameter. I took 1/8th inch diameter roll solder and plugged all of the holes except the two that were needed to lube my bullets. This was pretty easy; I just left the metal rod inside the die, then stuffed the solder into the holes one at a time and cut them off. With the stubs of solder in place, I seated them by pounding with a copper hammer. Then I put the die in a padded vice and filed the excess solder off with a non-ferrous metal file. Finally, I gave the inside of the die a quick dress-down with #320 sand paper. With these excess holes plugged, the lube only goes through the two that I want and very little excess gets between the rod and the bore of the die.
You'd think that a .44 is a .44, but it ain't necessarily so. I have a knack for encountering goofy challenges in the calibers I reload, so this one doesn't surprise me.
I already had lube/sizer dies in .429 and .430. The .429 came with my Lyman 450 lube/sizer, and I doubt if I ever would've used it as it is undersize for most .44 barrels now being made.
I'd heard on the Greybeard Outdoors site that Marlin .44 barrels are oversized. Since I had a sniff that something was different about my Marlin barrel, I decided to check this out. Sure enough, when I slugged the barrel it measures .432 across the grooves and .427 across the lands.
Here is a link to the whole story:
http://www.leverguns.com/articles/fryxell/microgrove-barrels.htm
If you read through that article, you'll see that the author suggests that there isn't anything inherently wrong with shooting lead bullets in Marlin microgroove barrels, so long as you get the bullet size matched to the size of the bore.
Therein lies the problem. Nobody makes a .432 or .433 sizer/lube die as a regular item; special orders are a possibility at high cost. A lee push-through sizing die can be custom ordered for, what, $30 or thereabouts, but that commits you to use liquid alox lube that isn't necessarily compatible with the design of your cast bullet. You can always use your bullets in their as-cast size if they come out oversized to approximately what you need, but then you are going to have to pan-lube them and that's not my first choice.
The bullets cast in my Lyman 4-gang mould block drop out at .433, just about a perfect size for my .432 Marlin-made barrel. My solution for lubing these was to take my .429 lube/sizing (Lyman calls them an "H&I die") and honed it out to .4325. I did this carefully on my drill press. I took a piece of dowel slightly over 3/8 inch, cut a kerf in one end, and inserted a small strip of Emery cloth which I wrapped around the dowel. Carefully, I honed out the H&I die making sure to rotate it around while honing to ensure uniform concentricity (as much as I could Mickey-Mousing it around such as I was). I used cast bullets to check it for size periodically while honing, and after not too long, I got it down to .4325. I made a quick pass with some fine sandpaper to finish it off .
Basically, the idea in this case is to use the H&I die for lubing only. I want the bullet in its as-cast size, but want to use the H&I die to perform the lubing process.
Part of the H&I die set is the metal rod that goes in the cylinder. The bullet sits on this rod (or round) inside the actual die while it is being sized and lubed and this metal rod is exactly sized to fit closely without friction inside the die. When you hone out the die, the bore size is greater than it ought to be in relation to the metal rod that fits inside it. The extra clearance between the die and the rod allows some sizing lube to leak out into the area underneath the bullet. When this happens, as you lube bullets you have to clean this out every pass or two, which is a pain in the neck. The H&I die has rows of holes along the sides to allow the sizing lube to flow into the lube groove on the bullet. Since my .44 bullets only have one groove, I only needed two whole open on the sides of the die, opposite each other spaced at 180 degrees. These holes are 1/8 inch diameter. I took 1/8th inch diameter roll solder and plugged all of the holes except the two that were needed to lube my bullets. This was pretty easy; I just left the metal rod inside the die, then stuffed the solder into the holes one at a time and cut them off. With the stubs of solder in place, I seated them by pounding with a copper hammer. Then I put the die in a padded vice and filed the excess solder off with a non-ferrous metal file. Finally, I gave the inside of the die a quick dress-down with #320 sand paper. With these excess holes plugged, the lube only goes through the two that I want and very little excess gets between the rod and the bore of the die.
You'd think that a .44 is a .44, but it ain't necessarily so. I have a knack for encountering goofy challenges in the calibers I reload, so this one doesn't surprise me.
