At what velocity does a Magnus #502 38 caliber wadcutter start leading a barrel?

[Bexar]

I read on here somewhere that low velocities could lead to leading. The box doesn't have a hardness rating it just says hard cast. I inherited the bullets and have never loaded cast lead before. I have 38 special and 357 mag cases to load them in.

Thanks...Bexar

 

[TimSr]

Too many unknown variables for anybody to even make guesses. Use standard lead load published data, observe results, and work from there. Don't start below published minimums.

 

[KSCCHTrainer]

Too many unknown variables for anybody to even make guesses. Use standard lead load published data, observe results, and work from there. Don't start below published minimums.

Like TimSr said, too many variables. Especially since the bore and rifling of each gun will lead (or not) at different velocities with the same exact bullets.

The only way you can determine this is try them in your own gun. Start at the minimum published load for that bullet (never go below this) and work up toward the maximum published load (never exceed this). Somewhere in between those two you may or may not experience leading of your bore. IF you do observe it on one load and not on a lower one, never exceed the last load that did not produce barrel leading.

This may be a laborious process but it's the only way your question will ever be answered correctly.

Jim

 

[Rule3]

Call him. I used his bullets years ago, Very nice and helpful

Cast are 16 to 20 BHN

As those are wad cutters you would not drive them very fast anyway I do not think.

 

[Walkalong]

Assuming they fit your gun well, then I would guess 600 to 900 FPS would be fine, but as posted, there are so many variables it is hard to tell. If your chamber throats are smaller than the groove diameter on the barrel, it will lead period. If they are a bit over, and the bullet fits the throats well, it should do fine, but it might take a minimum velocity to bump them up to seal things well, which may be faster than 600 FPS.

Pick out a load that shows around 700 to 800 FPS and try it out.

 

[GP100man]

Since having my throats sized exactly the same & the cones cut & polished . NO thread choke . My GPs seem to like lead better than ever .

I push my 8bhn wadcutters to 900 fps , all I have to do is wipe powder residue off , bores are shiney NO leading NONE.

Boolits .0015" over throat size, yes I lapped my sizing die out myself to .3595"

I now adjust my bhn to the speed/weight requirements.

It was really eye openin when I cleaned my cyl & DougGuy over on Ruger Forum.com started measureing, slugging is good , pin gauges are a lot GOODER!!!

But to answer your question ,post no. 2 is exactly where I`d start.

GP

 

[Sa-tevr]

Contact Magnus Bullets . Terry is a great guy to do business with.

 

[Bexar]

Contact Magnus Bullets . Terry is a great guy to do business with.

Thanks...will do Monday.

 

[Sam1911]

Contact Magnus Bullets . Terry is a great guy to do business with.

Call him. I used his bullets years ago, Very nice and helpful

The basic point here is that even HE can't tell you the answer to your question. As the others have said, too many variables. And even when all those variables are known, it will be pressure more than velocity that effects leading.

Cast are 16 to 20 BHN

Cast are certainly more variable than that, with anything from 6 to 30 being possible. The usual range for lead alloy bullets is more like ~8 to ~18 which tend to work well at common handgun pressures.

 

[mdi]

I've fired plain based lead bullets that barely get out of the barrel to 1300+ fps. They will lead at both ends of that spectrum, if they don't fit the gun. BHN of the bullet has less to do with leading than proper fit. I have found that for most of my revolvers, a good place to start is sizing the bullet to the same size/diameter as the cylinder throats. Measure the cylinder throats and bullet diameter...

 

[murf]

The type of powder used will also have an effect.

murf