376 groove diameter will a .379 mold be fine

[JTC]

I’ve got a 38-55 that is a Winchester 94 newer rifle I had recut to this bore and it’s groove diameter is 376 I wanna load cast for it and get a mold the guy who did the job told me to stick with bullets in the .376-.377 range. I can’t seem to find molds that size but I can easily find the ones that are labeled by lee 375 win /38-55 .379 will these work or will I have issues that will mean my cast will be 3 thousands bigger. I’m very very new to this and I have so much to learn. Thanks

[richhodg66]

The standard Lee I have drops them just a hair over .380. I shot them unsized in my .38-55, just dip them in heated liquid alox.

It's been my experience that bigger is almost always better for both accuracy and preventing leading. The biggest that chambers easily and will eject loaded rounds easily is what I'd aim for.

[Outpost75]

Load a few dummies with the as-cast and unsized bullet. If the dummies chamber easily in your rifle without forcing the action closed, and you can extract the loaded round without severely marking the bullet or rubbing the cartridge case, they are safe to shoot.

[JTC]

I can either buy the lee mold that are for the 379 bore or I can go for the Lyman brand that is for 376 also what did u mean by unsized bullets.

[farmbif]

the three most common moulds, two from Lyman and the lee mould were designed for 38-55. all three shoot well sized down in my 375 win lube sized down to .377.
they seat much deeper than the 200 or 220 grain jacketed bullets so case capacity is lessened. not a problem for me a 265 grain bullet moving at about 1800 fps will take down anything it hits. I use an imr4198 equivalent, reloader 7 and 1680

[JTC]

Ok so the lee dies that are the 379 would work for me after I mold the bullets do I have to resize them also my rifle is 376 groove

[farmbif]

ok so your Winchester 94 was a 30-30 and you had it rechambered and bored to 38-55? is that correct? the way you asking I'm guessing you don't have a sizing die and your going to powder coat or alox pan lube them. the only way to know is to try them and see if they will chamber. I'm not an expert but if it chambers without a problem and they are cast of wheel weights, an alloy that is not super hard, I would try them and see what they do with a starting load of powder from a reputable reloading data source I shoot cast bullets sized at .311 in a .308. with great success.

[JTC]

Farmbif your correct it was a 94 30-30 rebored to 38-55 and the groove diameter is .376 but the molds I see are like .379 I just wondered if that would be too big running in that bore of the 38-55. Seems to me that running lead wheel weight cast bullets at a few thousandths wouldn’t be a problem

[richhodg66]

I can either buy the lee mold that are for the 379 bore or I can go for the Lyman brand that is for 376 also what did u mean by unsized bullets.

Unsized means unsized. Shoot them just as they drop from the mold after applying some kind of lube, I use the Liquid Alox White Label Lubes sells, but I believe it is exactly the same stuff as the Lee liquid alox. I warm it up a little in an old musket cap can on a coffee cup warmer and dip the bullets in it up to the crimping groove. They shoot well and don't lead. There is a lot of criticism of Lee products, I'm not a basher, not a fan boy either, but generally Lee bullet designs are good, basic designs that tend to work pretty well across the board for they caliber they are, nothing fancy.

I think you're obsessing too much over a couple of thousandths of an inch. Cast bullets are much more elastic than jacketed, the throat and bore will size it to what it likes safely. As stated, shoot the biggest diameter bullet that will chamber easily and that aloaded round will extract easily. If your rifle will do that with an unsized bullet, you are there, no need for a sizer.

I don't know how much reloading experience you have or if you're bought a set of dies yet. Let me make a recommendation; spend the extra money and get a set of the RCBS Cowboy dies. I only shoot cast in mine and got mediocre accuracy with it using a regular set of dies, switching to the Cowboy dies cut the group size by more than half without changing anything else, it was that dramatic.

[JTC]

Thanks I appreciate it yeah I’ve been prolly over thinking it too much, I will look into the rcbs cowboy dies. Also looked at some Lyman mold too 376 is what it says on it.

[richhodg66]

Thanks I appreciate it yeah I’ve been prolly over thinking it too much, I will look into the rcbs cowboy dies. Also looked at some Lyman mold too 376 is what it says on it.

Most molds drop bigger than what the nominal diameter says. If it says 376, it probably drops 378 at least. So far, I've been pretty impressed with that Lee bullet and their molds are cheap, you won't be out much if it doesn't work out. I find Lee's one and two cavity molds more difficult to get good bullets from than an iron mold, but I have learned their quirks now athd that mold drops good bullets for me.

The .38-55 is a very easy cartridge to load for. I keep mine low, I shoot either 10 grains of Unique or nine grains of 700X behind just about any bullet weight and it works well out to 100 yards, as far as I shoot.

[JTC]

Thanks I appreciate it yeah I’ve been prolly over thinking it too much, I will look into the rcbs cowboy dies. Also looked at some Lyman mold too 376 is what it says on it.

[JTC]

My other question would be is it safe to use cast bullets with jacketed bullet data of the same weight

[richhodg66]

Maybe, but there's enough cast data out there that you should use the correct data. Even if the data is not for the exact bullet design, it gives you a start point, you can generally use data for a heavier bullet with a lighter one and be safe.

Here is where I would start, best cast manual ever. http://marvinstuart.com/firearm/Manuals/Bullet%20Casting/Lyman%20Cast%20Bullet%20Handbook%20-%203rd%20Edition%20-%201980%20-%20Reduce.pdf