Is .458 too small?

[awaveritt]

I just bought a Lee 457-405-FN mold (plain based). With my alloy, it drops at .458. I was hoping for a little larger diameter so I'd have room to size down depending on the rifle. The catch is, I do not yet have my Marlin 1895 but am wondering if some of you could tell me what new Marlin (non-microgroove) barrels are slugging out at? I know this varies but some anecdotal evidence would give me an idea. Is my .458 dia. cast boolit going to be too small, do you think?

I know, I'm a little OCD, but humor me:)

[6pt-sika]

I shot that exact bullet in my 1895CB and I never sized the bullets . Tumble lubed and shot as dropped .

Now I am sizing at .459" but am waiting on a new .461" die .

[missionary5155]

Good afternoon
All my Marlins are FAT throated !
BUT maybe your new one will be normal.. BUT I will be surprised. When it arrives slug the throat area and you will know. The barrel will most likeñly be around .459 BUT the throat is the most important measurement. I have a Trapdoor that Needs a .463 and swages it down just fine at the .459 muzzle.
BUT you can Beagle your mold.. that will give yo the .003 you most likely will need.
Or you can give that mold a lap job and have it throw .461 boolits.
But there are simple solutions. Your mold will work... but may need a little help.

[jh45gun]

I shoot the Lee 405 grain .459 Hollow Base sized at .459 and it is very accurate in my guide gun but then I think that hollow base may help somewhat.

[rhead]

Mine will shoot a .459 adequately but does better with a .462. The bore on mine is .458 but the throat is huge.

[BABore]

Most all of the Marlin's I've slugged run 0.4582 to 0.4587 groove. Every one I've loaded for will safely chamber a 0.462 diameter boolit. As mentioned above, throats run big. Fill the throat and accuracy will be there.

Alot of people complained about the older MicroGroove rifling being real shallow. Some say they won't shoot cast and they are full of it. They just like big boolits at 0.460 to 0.462. MicroGroove rifling runs 0.0025 to 0.0032 deep at best. Now for the big surprise. The new "Ballard Cut" rifling is roughly the same depth. I also believe that it is not cut, but rather button rifled. This rifling is a bit more forgiving on boolit diameter, but they still shoot best when they're big enough to fill the throat. The original Ballard cut bbl's were cut and the rifling is at least 0.004" deep. I have a PITA 35 Rem. that has a 0.350 bore and 0.3635 grooves. That's almost 0.007" deep and it doesn't grip a cast boolit nice. Just had to make a special mold for it.:bigsmyl2:

The biggest problem I see on most Marlin's is they usually have bore constrictions under the dovetails and bbl thread. They need to be shot or firelapped out before good accuracy is realized. Slug the bbl all the way through and then do a second slug just into the muzzle, then back out. Compare the two diameters. The muzzle only slug should be the smaller of the two.

[jh45gun]

Yea I have noticed the Ballard Rifling is not that deep. They shoot well though.

[Bullshop]

Filling the throat is one way and works but often requires a custom mold that will drop a larger than standard diameter.
For anyone that has a production mold that only drops at say .457" all is not lost.
Boolits of less than groove diameter can be made to work just as well as any other by matching the alloy hardness to the correct powder burn rate.
If this were not true then how on earth are those involved with long range BPCR shooting at international level producing such outstanding results using boolits patched anywhere from .450" to .454" diameter in .458" groove barrels? Its not that BP and PP is magic. The same thing can be done with smokeless powder and grooved boolits. The general rule to go by is that the alloy has to be fairly soft and the powder burn rate fairly fast.
If I were to try and put limits on it I would say alloy of not harder than bhn 9 and burn rate of not slower than say 4227. Not absolute on that but just a guide. Stay inside those numbers and things should work well.
So if you have a production mold that will only produce boolits of less than groove diameter for your rifle and your finances will not allow another fret not, it can be made to work well.
BIC/BS

[6pt-sika]

Alot of people complained about the older MicroGroove rifling being real shallow. Some say they won't shoot cast and they are full of it.

I wish I had $10 for every cast bullet I've fired thru a Micro groove barrel in the last 10 years !

I wouldn't a be a millionaire but I'd have a right nice stack of money !

I to thought Micro barrels weren't for cast either until Ranch Dog showed me the light :idea:

[awaveritt]

For the record, I've never bought into the notion that micro-groove barrels couldn't shoot cast very well. I made the distinction in my OP simply because I'm planning on purchasing one of the new Marlins, probably the cowboy. That said, I wish I had been a caster years ago when I had a circa 1980 Marlin 336A (half tube/24" barrel) that routinely sent 170gr. Sierra J-words into 1 1/2" with that micro groove barrel. Of course it wore a 4x Leupold at the time and my eyes (and nerves) were much steadier then.

I won't fret over my .458 mold until the rifle is here. Then as some have stated here, I'll see if I can't open it up a little, if that's what it needs. Thanks for all the input.

[WyrTwister]

I just bought a Lee 457-405-FN mold (plain based). With my alloy, it drops at .458. I was hoping for a little larger diameter so I'd have room to size down depending on the rifle. The catch is, I do not yet have my Marlin 1895 but am wondering if some of you could tell me what new Marlin (non-microgroove) barrels are slugging out at? I know this varies but some anecdotal evidence would give me an idea. Is my .458 dia. cast boolit going to be too small, do you think?

I know, I'm a little OCD, but humor me:)

My Marlins like big bullets .

I started out with that mold . Shot fine , up to ~ 1150 fps , then the groups went wild .

Bought the Lee .457" bullet die & that made it worse . That was the biggest one in their catalog , w/o going into the next size / caliber .

You can paper patch them with cigarette paper & it helps some .

Or I hear you can lap them a little larger ?

What I shoot now is the Lee 405 grain HB bullet . It is a slightly bigger mold & works better .

I cast wheel weights and any other lead I can find . I cast just as low a temperature , that I can . And still get good bullets .

I tumble lube my bullets . Originally shot them as cast . But some of the loaded ammo was too big to chamber right . So , my cousin and I lapped the .457" die out to .460" . These feed fine and shoot great .

These can be loaded hot enough to rattle your ancestors . Or to cream puff level .

Both of my rifles are standard 20" or 22" . Wish I had also bought a ported guide gun when they were in production .

God bless
Wyr