Can one resize .410 bullets to .401?

[El Bibliotecario]

I have a supply of bullets intended for the .41 Magnum round, cast from wheel weights and sized .410. Is it practical to resize them to .401? for use in .40 caliber cartridges? TIA

[country gent]

Normally sizing is recommended for up to around .002-.003 reductions. Your wanting .008-.009. This could possibly be done in push thru sizing dies in 2 passes. This much in one pass may not size down but shave down removing metals. I would recommend if doing this a very high polish and slightly longer leade into the die to help sizing the bullet down. The added leade also helps to center and alighn the bullet the high polish eases force and slows the rubbing slight scraping of lead from bullet. A custom push thru sizer with a leade into it 1 bullet dia long to size and polished to a mirror finish may do it in 1 pass in a good press. Having the bullet pre lubed will help maintain lube grooves and lubricate the die.

[beagle]

You can but they'll be really distorted and may not give the accuracy you need. Normally you can get by with .005" and they'll do all right but that's really pushing the envelope. When nose first sizing, you're actually swaging the bullet. It elongates and the lube grooves squeeze in smaller and the base may grow fins dependent on your sizer setup. You're better off to work out a trade for .40 bullets with someone./beagle

[bob208]

only 2ways to do it throw them in the pot and recast them or trade them to some one that has .401 bullets.

[Kraschenbirn]

only 2ways to do it throw them in the pot and recast them or trade them to some one that has .401 bullets.

+1 on this. Sizing down boolits cast from straight COWW that far will not only result in serious distortion but will pretty much remove the lube grooves at the same time.

Bill

[El Bibliotecario]

Thanks to the above commenters for reinforcing my suspicions. I concur with either trade 'em off or melt 'em down.

[303Guy]

I have successfully sized 357 boolits down to .31 in a push through die with a long leade (one step). Even so, sizing as cast irons the lube grooves out - i.e. the boolit distorts. However, fill the lube grooves with lube and the grooves remain pretty intact. The problem would be access to a lathe to make the suitable die or dies.

[AntiqueSledMan]

I agree with 303Guy, I've sized .458 down to .452 but the lube grooves are almost gone. I did this for shooting in a sabot so I wasn't to concerned about it.

AntiqueSledMan.

[Green Frog]

Going from .410" to .401" is not sizing, it's SWAGING! Like somebody else said, either swap them or melt them and try again if you want good bullets that much smaller. Of course this is JMHO, YMMV!

Froggie

[mart]

Here's some input from someone who has done exactly what you are asking. I have a 401 Powermag. Early on, before I had any molds for it I decided to size some bullets from .411 to .403 to fit the bore of my Powermag. I tried a 220 grain SCW, a 230 grain TCFP and a 280 grain WLNGC. I did it on one pass through a Lee push through die. They shot very well. Yes the crimp groove gets reduced considerably and on some bullets may even disappear if it had a small groove to start with. I sized these after they were already lubed, based on the advice from another shooter who had tried the same thing. All of these bullets have a substantial lube groove so I was unconcerned about loosing that groove.

Here are the bullets in the same order as listed above.



And a couple of targets shot at 25 yards with the 220 and 280 grain bullets.

[GLynn41]

I have a friend from another forum and he has taken my .41s and sized them down and for him they work very well

[bdicki]

Before the 10mm and 40S&W I pick up a swaging die for a friend for his 38-40, it was designed for just this. It worked on jacketed bullets in a rock chucker, I think RCBS die but not sure. It left a little skirt at the base.

[dondiego]

Swaging dies usually make bullets bigger???????

[S.R.Custom]

Back in the day, I sized .410 215 gr LSWC down to .402 for use in a Springfield Omega I used for pin shooting. They were the most accurate boolits I ever shot from that gun... Less than 1" at 25 yards.

To do it, I used two Lee push through sizers that each squeezed .004" from each boolit.

[mart]

Swaging dies usually make bullets bigger???????

Correct. Swaging bullets makes them larger. Drawing bullets makes them smaller.

[lightman]

Its been done successfully but much over .002-.003 is generally considered to be detrimental to accuracy. You will loose a lot or maybe all of your lube and crimp groove. It will also be hard on the linkage on a lubrisizer unless you're using a push thru die on a loading press. Personally I would melt them and cast something closer to what I needed.

[mart]

Lots of speculation on why it won't work. A couple posts from guys who have actually done and it did work. If it were me I'd get a Lee push through and try it with already lubed bullets. The lube grooves on the bullets I tried were plenty deep to survive the amount of resizing you are wanting to attempt. Some crimp grooves will survive, some wont. A lee push through is cheaper than a new mold, especially if you already have .410 cast bullets.

[lightman]

Lots of speculation on why it won't work. A couple posts from guys who have actually done and it did work. If it were me I'd get a Lee push through and try it with already lubed bullets. The lube grooves on the bullets I tried were plenty deep to survive the amount of resizing you are wanting to attempt. Some crimp grooves will survive, some wont. A lee push through is cheaper than a new mold, especially if you already have .410 cast bullets.

You have certainly proved that it can be done and I can't argue with that. Even though its been done successfully I personally would buy a mold more suitable for the cartridge. The pictures of your target sure shot holes in the theory that sizing more than .002-.003 hurts accuracy! Good info!

[rintinglen]

I routinely take .358-429 boolits and size them to .350 for use in my .348 Winchester. There is no reason you can't turn your .41's into 40's. Buy a LEE .401 sizer, polish it out to.405. Lube your boolits with LLA, then run them through your modified sizer. Finally, size them through your normal .401 sizer.

[airone46]

Goodmorning everyone.
Maybe I'm o.t.!
But recalibrate from .312 (mold Lee .312 TL: MOLD DC CTL312-160-2R) a. 308/309 is possible ???

This mold has a design that I really like and I would like to use it for the 7.5x55 Swiss!

I would not have problems for the lubing groves (TL series): I would use the coating method!

Thanks