leading with hardcast bullets

[cjwils]

This might have been addressed before, but I cannot find it.

When reloading high velocity revolver loads, is it really true that hardcast lead bullets cause significantly less barrel leading than regular lead bullets?

[jepp2]

When reloading high velocity revolver loads, is it really true that hardcast lead bullets cause significantly less barrel leading than regular lead bullets?

Depends. How high do you consider high velocity? What is the BHN for the "regular lead bullets"?

I consider fit and lube more critical to leading you are likely to encounter than hardness. However:

- too soft a bullet driven too fast will lead
- too hard a bullet driven too slowly (fails to obturate properly) will lead
- too small a bullet for the groove diameter will lead regardless of how hard or soft
- wrong lube can cause leading

This might be helpful link

And so might this link

[FrankenMauser]

Worry about diameter, and how it fits your firearm(s), before worrying about hardness.

[mehavey]

- too small a bullet for the groove diameter
will lead regardless of how hard or soft

Which means, gentle readers, that if the cylinder throat is smaller than the groove diameter,
leading is almost surely a factor no matter what.

[57K]

All good and relevant points. Really, anything over 18 BHN isn't really necessary if all of the previous conditions are met. Being at least .001" above groove diameter is the key, but with revolvers, throats must not be undersized as mehavey mentioned. 17 - 18 BHN bullets are so commom these days that they are what I generally buy. Even in .45 ACP with velocities just over 800 FPS in some cases, I just don't have any problem with leading using properly sized bullets. Some reloaders even prefer their cast bullets be a minimum of .002" above groove diameter.

[NWPilgrim]

Although I have reloaded for over 25 yrs and follow the +.001" rule, what is the reasoning of it? I mean, if the groove is .429" then how does having a bullet any greater diameter than the space available have any effect?

Likewise, if +.001" is good then why not +.002"?

Not something I pondered before, just did it. Any explanation how it works?

[Mike / Tx]

Although I have reloaded for over 25 yrs and follow the +.001" rule, what is the reasoning of it? I mean, if the groove is .429" then how does having a bullet any greater diameter than the space available have any effect?

Likewise, if +.001" is good then why not +.002"?

Not something I pondered before, just did it. Any explanation how it works?

Notably if the bullet is .001 oversized it will make up for little imperfections in the bore. Also most correctly dimensioned chamber mouths in revolver cylinders are at least bore sized or a touch bigger, some are smaller as Mehavey said and this is something which should be checked. If they are smaller they can be reamed or polished out to the proper dimension. If they are bigger or some big some smaller they should be polished or reamed all the same which might end up being .002 or even .003 bigger than the bore.

Also the forcing cone can play a role in leading as well if it is smaller than the bore size. Some go as far as to put a taper on them to minimize this issue.

Also the section of threaded barrel where it is screwed into the frame. If screwed in too tight it will squeeze the barrel down in that area which will drive you nuts with cast until it is corrected.

Just a few of the things which can result from using bore sized bullets in revolvers. For semi auto and rifles it is easier to start off .001 or .002 bigger to ensure a good seal down the bore. The cast lead is WAY softer than the copper jacketed bullets, and once fired it will easily conform to the actual diameter as it passes from the case mouth through the rifling lead and down the bore. Usually as long as you have no chambering issues they will shoot just fine and in some case more accurately.

[noylj]

>Likewise, if +.001" is good then why not +.002"?

Yes, now you understand. A 0.357-0.358" lead bullet will almost always perform better than a 0.356" bullet--even in a 0.355" groove. A 0.452-0.452" lead bullet will almost always perform better and a 0.452" lead bullet in a .45. Why? I don't know, I just compare group size and go from there. In fact, I did that in the mid '70s and concluded that sizing does NOT make a more accurate bullet and shooting as-cast was always as accurate or more accurate than sizing bullets. I haven't used a Lubri-sizer, except for rifle bullets, since I discovered pan lubing and when I did use a lubri-sizer, the sizers were always nominal as-cast diameter or 0.001" larger, as all I wanted was the lube grooves filled with lube.
Isnt it amazing that what we now call soft was considered HARD just a few years ago. Elmer Keith developed his .44 Mag loads with a 10-13BHN alloy and didn't suffer leading. Why? He knew how to fit a bullet to the gun. It isn't rocket science and you can read lots on the 'net.
An undersized HARD bullet will lead a LOT. An undersized "soft" bullet will not lead or lead much less as it can be "bumped up" to fill the bore.
Getting a bullet that is a tight snug fit in the cylinder's throats and is AT LEAST 0.001" over barrel groove diameter will eliminate almost all leading.
Running a tight brush with "Chore Boy" copper (not copper-plated steel) "filaments" wrapped around it will eliminate leading in just a few passes.
Using Lee Liquid Alox, or White Label Xlox, will eliminate almost all leading from bullets that cause some leading.
There is this great theory about matching an alloy and its yield point to the pressure of the round. However, if the bullet is sufficiently large, it really doesn't matter about alloy in my experience. I cast thousands of bullets with wheel weights and gas checks and shot at up to 2300fps in my rifles without a problem--good fit and good lube.
Commercial bullets are all way too hard and generally lubed with blue crayon (at least, they crack and fall out like pure paraffin wax). I like to get the "soft" alloy bullets from mastercastbullets.com and Missouri Bullets (and Penn, in the bullets they offer it in).

[Paul B.]

I have shot my home cast bullets in the .357 Mag.as soft as 8 BHN over 14.0 gr. of A2400 without any leading. Proper sizing is the key. The barrel slugged out at .3575" and I size the bullets at .359". The lead I as using to make the bullets was given to me and purported to be wheel weight metal. Probably 85 to 90 percent stick on types I'm guessing. I'll probably add a bit of linotype though and toughen them up a bit. Try for about 11 or 12 on the BHN scale.
Paul B.

[WESHOOT2]

As the OP stated, "hardcast" vs "lead bullets".


Hardcast lead bullets are hard.

Swaged lead bullets are soft(er).