Sizing Limits

[jcnull2305]

I'm getting ready to order a mold from Precision (the 54-510M). I slugged my bore, and took several measurements, and it's slugging right at .540 at the lands. I figured that .541 would be the way to go for loading ease with both clean and fouled. My question is, and I'll be damned if I can find an answer anywhere, is how far down can I go in sizing? I kinda want to order the mold slightly larger for insurance purposes (like, if I get another .54 with a slightly larger bore diameter, and need to size a bit larger). How many thousandths can I get away with before it becomes problematic? Could I go with a .543, and size down to .541 without an issue? It looks like Accurate cuts the lube grooves to about .5, so I'd be looking at around .041 to .043 or so for grove depth, if I'm reading that correctly.

And I am going to do away with the bevel at the base.

Thanks,
Jim

 

[52Bore]

Here is a .457 Pure lead bullet ran thru a piece of barrel of my Knight 500, which is .451”
Note the grooves of the barrel did not touch the OD of the bullet as they are deeper.
I used a razor blade to cut off excess flat to the base.
0.001” over is a good thought.. keep sizing to a minimum.

 

[Idaholewis]

Having to Size More than .002-.003 is LESS than ideal, Therefore when ordering a Mold i like to be No more than .002-.003 Over size. That said, I have sized bullets MUCH MUCH Farther than this with no problems whatsoever, LUBE Is VERY Critical When doing so, and i Go in Steps.


I just copied Accurate Molds Tolerances here, and added .541 as example. MAKE SURE YOU READ and Understand this

I want an "as cast" diameter as close as I can get to .541".

I have a diameter tolerance window of .002" for my molds.
When ordering a diameter such as .541", you can select:

• Positive tolerance (+.002/-.000) means the diameter will be AT LEAST .541" But could be as much as .543
• Negative tolerance (+.000/-.002) means the diameter will be AT MOST .541" but could be as small as .539
• Centered tolerance (+/- .001) means as close as possible to .541" Could be .540, .541, .542

Positive tolerance is usually desirable for driving bands.
Negative tolerance is usually best for bore ride noses or any application where a certain diameter cannot be exceeded and a sizing die won't be used on that portion of the bullet.
Centered tolerance might be desirable when powder coating, and tapered designs.

Using "Special Notes" on the online order form, you can refine your diameter request for bore ride, body diameter, whatever, to the 4th decimal place. Ordering to the half thousandth does not ensure precision to the half thousandth, it only helps you communicate the desired diameter range within that .002" window.

My mold cavities are actually turned to +/-.0001" tolerance, but I cannot guarantee resultant casting tolerance closer than .002" because of casting variables such as pour technique and temperature, mold block temperature, purity of alloy, etc.

 

[Idaholewis]

I Routinely size .457-.459 Bullets down to .449-.451 For my .45s with ZERO issues, I own about every .457-.459 Mold that Lyman Makes, and ever has made

Here is an Example of how far i have successfully sized Bullets, Again this is NOT Ideal by any means, This is Just to show it can be done without Damaging the Bullet, if done Correctly

This is a .45 Colt Pistol Bullet, Drops from my Mold at .454

And here it is Sized to .442

 

[jcnull2305]

Thanks for the replies, gentlemen. I ordered the mold from Tom at .541, and to hell with hypotheticals.

it can be done without Damaging the Bullet, if done Correctly

Lew, I've asked you enough dumb questions that you should know that I ain't ready for multi-down-sizing operations yet!

 

[Idaholewis]

Thanks for the replies, gentlemen. I ordered the mold from Tom at .541, and to hell with hypotheticals.


Lew, I've asked you enough dumb questions that you should know that I ain't ready for multi-down-sizing operations yet!

You will be GOOD TO GO with that Bullet Ordered at .541 POSITIVE Tolerance, I bet the Bullet ends up at .542-.543

 

[jcnull2305]

l be GOOD TO GO with that Bullet Ordered at .541 POSITIVE Tolerance

Yes, sir. That;s exactly what I did. Requested .541" bands with the tolerance at +.000" - +.002",, and no bevel at the base, specifying pure lead as the alloy. Ordered the Mold in steel, as well, per our other conversations. (I'm becoming quite the IdahoLewis disciple, but your're saving me a lot of work).

As per my thread on sizing dies, I ordered a threaded push-though die in .541 from Northeast Trade Company (HOME | home). They have a pretty good selection of steel threaded and non-threaded (for an arbor press) dies, and can make other sizes on request. They are super people to deal with. Send them an email and you'll get a phone call that day to discuss your needs. They have a machine shop on premises.

I've gotten all my molding gear, even a set of nice, heavy welding gauntlets. Just have to dig out my assless chaps from my horse training days in case I ladle some lead on my legs while casting!

 

[Idaholewis]

You will be turning out AWESOME Bullets in no time Just Follow my Casting Video, Tip Stuff, Everything is there, If you have any Problems just Shout.

When you Get your new mold, Clean it REALLY Good to Remove The Machining Oils, I use Dawn Dish Soap with a Nylon Bristle Brush and Scrub it good, Then Blow it off Dry with my Air Compressor Nozzle. You can also Spray it down good with Brake Cleaner to De-Grease it (I do this as well)

Set your Sprue Plate like i show in the Recent Video, Find that Point where the Sprue Plate will “Just“ Swing open when you “Flick your Wrist”

With Pure Lead the KEY to Success is Getting that BIG HEAVY Steel Mold HOT, And cast HOT, About 800 Degrees

When you get done Casting, Be sure to Coat your New Iron mold with a Preservative Oil, They can/will Rust Fairly Quickly depending on Environment? The Old Saying “an ounce of prevention is better than a Pound of Cure“ Rings VERY TRUE Here. An Aerosol Can Oil is Sure nice, Rem Oil Works Great

 

[edmehlig]

(I'm becoming quite the IdahoLewis disciple,

I think Lew has converted quite a few disciples here! Besides what Lew mentioned about cleaning the mold etc. When I’m ready to start casting I’ll clean the mold with brake cleaner and then use Q-tips to wipe the insides of the mold and bands. Then I’ll take a toothpick and go against both sides of each band to make sure each band will have a clean sharp edge. It may not be necessary but it’s part of the routine I follow.

 

[Saxtonyoung]

I too have taken several of the the Lyman .458 - .459 bullets and sized them down as far as .450 and had excellent success shooting them out to 250 yards.

 

[MSalyards]

I just can't (or don't) want to picture a man casting or working horses in ass less chaps!

 

[jcnull2305]

I just can't (or don't) want to picture a man casting or working horses in ass less chaps!

Your reaction is perplexing... I mean, is that wrong??

 

[Saxtonyoung]

Great, now I got to get that picture out of my head.

 

[edmehlig]

I too have taken several of the the Lyman .458 - .459 bullets and sized them down as far as .450 and had excellent success shooting them out to 250 yards.

Only if they are lubed first. If not you will get finning around the base of the bullet.

 

[Saxtonyoung]

That's correct, should always use lube especially when sizing down this much.

 

[Idaholewis]

As I’ve said before, I even Pre-Lube my Sizing Dies, if not, The 1st Bullet will Likely be Ruined.

One more thing that is CRITICAL When sizing Lead Conicals Is speed, When Sizing a bullet you want to Send it ALL THE WAY through the Die Quickly, DON’T Stop and try to Re-start, NO AMOUNT of Lube will help if you Stop & Re-Start, Ask me how i know

You might ask Why one would Stop & Re-Start through the Sizing Process? I have a Habit of doing it, for comfort. My Press (Redding BIG BOSS) Has a Long Stroke, I start by “Pulling“ the Handle, about halfway through the Press Stroke i like to Switch and Push. This is a Recipe for DISASTER When Sizing Lead Conicals, EVEN Lubed. When you Stop to reposition, The Bullet will “Stick” in the Die, When you try and Start again, The Bullet Won’t Budge, You now have to put a LOT of Force on the Handle to get the Bullet moving again, This RUINS The Bullet, The Base will be Destroyed

The Crazy part is, this same Bullet that will STICK If you Stop & Re-Start, Will Slip through the Die EFFORTLESSLY as long as you Send it ALL the way through the Die Quickly