Did I get the right mould?

[phishroy]

Well, I just started casting for my 45-70 marlin.
I bought one lee mould and now im not sure if I bought the right one.
Its written on the box: 457 diameter weight 340 grain.

457-340-F double cavity.

After I casted a few I measured the diameter and it ranged between 452 to 456.

Im thinking that might be too small a diameter for my rifle.
I rather go larger than small to prevent gas cutting.
Am I missing something? Would this mould work for a 45-70?

[MtGun44]

You need to slug your barrel. They are most likely too small, most Marlins
work best with .458 or .459. You are right on too large rather than too
small.

Try casting hotter and maybe a different alloy to increase the diam.

You can also 'beagle' the mold (use the search feature - "beagle a mold")
to increase the diam, or lap it out with a boolit and very fine abrasive.
Beagling is basically using aluminum tape spacers to keep the blocks
from fully closing, increasing the diameter of the casting.

I have had excellent results with a RCBS 405 GC mold in my Guide Gun.

Bill

[1874Sharps]

PhishRoy,

The first three numbers on the Lee mold are a little misleading. Perhaps with a certain alloy(s) it will cast boolits at 0.457", but several I have cast at 0.459" to 0.460". The proof is in the pudding. Give her a try! I think you chose a good mold and bullet style and weight for your purposes. Good luck and good shooting!

[runfiverun]

if they come out that poorly sized either you got something wrong or the factory did.

[geargnasher]

I have that exact mould, and it casts .457" on the money with Wheelsweights + 4% 50/50 solder. I size these to .452" (a bit of a stretch) and shoot them in my Ruger Vaquero over 9.0 grains of HS6, a real thumper for the pistol.

My experience with the 45/70 is limited, but I've loaded for it a time or two and as I recall the gun liked heavier boolits (505 grain) and about .459", but dimensions vary widely for that gun so slug your barrel, use ONLY a good C-clamp 0-1" micrometer (NOT calipers) and measure carefully. try to get .001-2" over groove diameter.

Gear

[phishroy]

if they come out that poorly sized either you got something wrong or the factory did.

well, they are coming out out of round. they seems to be wider close to the seem and thinner on the other side.
i checked a few , about 10 of them out of the 50 i cast.

[Guesser]

I have that mold, mine drops at 457/458. I hand or LLA lube and shoot in a Ruger # 1 over SR4759 at 1500 FPS using a mixture of found and gifted cases using Standard primers. Seems to work well for me.

[Dale53]

I have the Lee 340 gr and it shoots extremely well in my Marlin 1895 45/70 (1.5" at 100 yards).

Dale53

[runfiverun]

sounds like they didn't get the halves fully closed when cutting it.
i know lee don't cut their molds but that's how it sounds.
i'd e-mail them or call.

[bigboredad]

by chance are you smoking your mold? I have the same mold I use it for my blackhawk so I smoke the mold heavy so I don't have to size down so much but I love that boolit and that mold is the easiest to cast with that I've used

[fredj338]

PhishRoy,

The first three numbers on the Lee mold are a little misleading. Perhaps with a certain alloy(s) it will cast boolits at 0.457", but several I have cast at 0.459" to 0.460". The proof is in the pudding. Give her a try! I think you chose a good mold and bullet style and weight for your purposes. Good luck and good shooting!

I must be lucky, like you mine casts right around 0.458" from ww. They just size in my Star @ 0.458". I haven't gotten to shoot any yet, but the Marlin GG is certainly accurate w/ jacketed bullets.

[carpetman]

Dont smoke your mold--just put it between your cheek and gum.

[phishroy]

Well, I tried to use one of the bullets I casted with this mould to slug the barrel, needles to say it was a bit of a waste of time since the bullet didn’t even fill in all the rifling grooves.

[canyon-ghost]

:coffeecom You caught that about bar solder, right? I think the addition of pure lead or nearly might be making it cast larger. Or possibly making it fill out better. The alloy you use can do that although, I'm not sure how much difference it would make.

[quack1]

I got that mold about 8 years ago,my first Lee mold, it dropped bullets at .456 with my usual mix of ww plus a little tin. Could never get it to shoot better than 4-5" at 100 yards, and it leaded pretty bad. I just figured it was a cheap mold and I got what I paid for. After finding this site and reading about beagling, I tried it. Got the mold to drop fatter bullets, leading dissappeared and got consistent groups of 1" to 1 1/2" at 100 yards. Can't ask for much better than that.
I have to give this site and the vast amount of knowledge here a lot of credit. I have been casting since the 60's and managed to learn a good bit from trial and error, but have learned a lot more in the comparetively few years I have been on this site.

[725]

Frustrating when these problems pop up. You can send it back or attempt to fix it yourself. You have to decide. If I were to fix it, I'd clean any "smoking" out of it, cast a few and use them to lap out the mould. Insert a stem in the base of the offending boolit, slather a little abrasive around the slug and turn it while closing the mould back around it. Judicious and temperate speed should allow the molud cavity to enlarge and work into a more round finished product. Got to clean alot as you go, be mindfull of debris that may prevent fully closing, and finsih up with a good cleaning. It goes against all my intuitive thinking, but I've been having good luck with mould prep by taking a Q-tip and a very small amoutn of Kroil. Wipe the interior of the cavity with an oil soaked Q-tip and rub it about dry with the other end. Works for me.

[ph4570]

Send it back to Lee. They will replace it and the replacement will likely be ok after the usual fixes. Be prepared for a wait to get the replacement. Call them first.

I use the RCBS 300 and 400 Gr GC molds with good success in my Marlin 45-70 1895 CB. I have to beagle them to get to .459.

[chuebner]

I picked up the Lee 340 gr. mold about two months back and found mine cast at .457/.458 using about a 25:1 alloy. These bullets are too small for my Sharps (.458) bore or trapdoor (.460) bore but are perfect for my Numrich rolling block (.456) bore. I lube with LLA and these generally shoot into less than two inches at 100yd. Point being you have to slug that bore and fit your bullet to it. Best load so far is 23.5gr. of 4759.

charlie