Plating and coatings and gas checks, OH MY!

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Up until now the bulk of my reloading has been in 9mm, .38 spl and .41 spl using Berry's plated bullets which are only rated to 1250 FPS. Now I have managed to gather the cases and primers I need to go magnum but when I visit the various cast bullet companies I get no indication just how fast I can push their products. If they are coated bullets they just say "increased velocity", with the exception of Rushmore who says "under 2000 FPS". Even the few gas checked offerings I see don't give me a clue.
What is the rule of thumb when using cast, coated or gas checked bullets at magnum velocities?

Thanks
 
Up until now the bulk of my reloading has been in 9mm, .38 spl and .41 spl using Berry's plated bullets which are only rated to 1250 FPS. Now I have managed to gather the cases and primers I need to go magnum but when I visit the various cast bullet companies I get no indication just how fast I can push their products. If they are coated bullets they just say "increased velocity", with the exception of Rushmore who says "under 2000 FPS". Even the few gas checked offerings I see don't give me a clue.
What is the rule of thumb when using cast, coated or gas checked bullets at magnum velocities?

Thanks
A properly fit bullet can go as fast as you can push it in any of those cartridges.

I push a non gas check. Non coated. Traditionally lubed 357 with a top load of 2400 out of a rifle with an 18” barrel. It should be doing close to 1800 FPS. ZERO leading and accurate enough for my liking.

This also with a pretty soft alloy.

The key is bullet fit. If you can get some swaged soft lead round balls. Lube one up with some oil. Lube the barrel well and drive it through with a brass rod.

Measure the diameter of the recovered slug and add .001” to .002” diameter. That’s the size bullet you want to be ordering.

If it’s a revolver you want to do the same thing but also check the cylinder throats the same way. Or with plug gauges. The chambers can be inconsistent or oversized or even worse undersized.
If your bullet goes from .358” through .356” throats to a .357” barrel you’re going to have issues.
 
Up until now the bulk of my reloading has been in 9mm, .38 spl and .41 spl using Berry's plated bullets which are only rated to 1250 FPS.

I haven't seen much in the way of jacketed stuff for .38 going past 1200 or so. Maybe really light bullets like 85 gr, but a lot of the common stuff like jacketed 125's and 158 rarely make it over 1100.

9 I don't load because honestly its still relatively inexpensive to buy.
Using Fed 155 gr syntec and Fed 115 fmj as a side-by-side, there isn't a big difference in listed velocity.

I have seen some .357 hardcast data at around 1500, non gas checked. Might be in a lymans book.

Now I have managed to gather the cases and primers I need to go magnum but when I visit the various cast bullet companies I get no indication just how fast I can push their products. If they are coated bullets they just say "increased velocity", with the exception of Rushmore who says "under 2000 FPS". Even the few gas checked offerings I see don't give me a clue.
What is the rule of thumb when using cast, coated or gas checked bullets at magnum velocities?

The general rule of thumb is to just use any published load data like from Hodgdon or anywhere else. I'm not saying its the be-all end-all for load data but its a good start.
You can get a little bit more out of coated because of less friction, and plated will go a little faster.

I don't necessarily think the issue is leading,although it is a factor because you can mix all kinds of lead together to get a specific hardness or coat it/ plate it. I think the issue is once you reach a certain velocity, anything past that and the bullet starts to pull itself apart due to centrifugal force. Soft metal can only spin so fast, I think the jacket keeps it from doing that.
Now I wouldn't try pushing straight lead, but even the mixed stuff with a brinnel hardness of 18 or better has a breaking point.

Gas checks I've only really seen for-

Carbine rifle data
Heavy/ compressed mag loads using a fast powder. - Even some of the lead-loads on the site list non-gas checked up to about 1500 or so with 180's

I have pushed some heavy stuff without gas checks. It might be powder dependent? Could be gr weight thats a factor?
A 180 gr .357 doesn't have the same amount of displacement and bearing surface than a 400 gr 45/70, so I'm sure theres some kind of "white man magic smoke-stick' math that determines what needs a gas check and what doesn't.

The above info may help or hinder.
 
I haven't seen much in the way of jacketed stuff for .38 going past 1200 or so. Maybe really light bullets like 85 gr, but a lot of the common stuff like jacketed 125's and 158 rarely make it over 1100.

9 I don't load because honestly its still relatively inexpensive to buy.
Using Fed 155 gr syntec and Fed 115 fmj as a side-by-side, there isn't a big difference in listed velocity.

I have seen some .357 hardcast data at around 1500, non gas checked. Might be in a lymans book.



The general rule of thumb is to just use any published load data like from Hodgdon or anywhere else. I'm not saying its the be-all end-all for load data but its a good start.
You can get a little bit more out of coated because of less friction, and plated will go a little faster.

I don't necessarily think the issue is leading,although it is a factor because you can mix all kinds of lead together to get a specific hardness or coat it/ plate it. I think the issue is once you reach a certain velocity, anything past that and the bullet starts to pull itself apart due to centrifugal force. Soft metal can only spin so fast, I think the jacket keeps it from doing that.
Now I wouldn't try pushing straight lead, but even the mixed stuff with a brinnel hardness of 18 or better has a breaking point.

Gas checks I've only really seen for-

Carbine rifle data
Heavy/ compressed mag loads using a fast powder. - Even some of the lead-loads on the site list non-gas checked up to about 1500 or so with 180's

I have pushed some heavy stuff without gas checks. It might be powder dependent? Could be gr weight thats a factor?
A 180 gr .357 doesn't have the same amount of displacement and bearing surface than a 400 gr 45/70, so I'm sure theres some kind of "white man magic smoke-stick' math that determines what needs a gas check and what doesn't.

The above info may help or hinder.
The twist rates in pistols should not get your bullets rpm so fast that your bullets go poof .
 
Up until now the bulk of my reloading has been in 9mm, .38 spl and .41 spl using Berry's plated bullets which are only rated to 1250 FPS. Now I have managed to gather the cases and primers I need to go magnum but when I visit the various cast bullet companies I get no indication just how fast I can push their products. If they are coated bullets they just say "increased velocity", with the exception of Rushmore who says "under 2000 FPS". Even the few gas checked offerings I see don't give me a clue.
What is the rule of thumb when using cast, coated or gas checked bullets at magnum velocities?

Thanks
1. Proper size cast bullet helps
2. Gas checked cast bullets can eliminate the base over expanding and lead “vaporizing” and leading your bore
3. Cast bullets with out gas checks need to be correct size and be pushed at the correct speed / pressure and bullet hardness to get proper expansion
A “rule of thumb”
Take published load data PSI of a given load
Lets say 20,000 psi dived by 1279.8 and thats your bullet hardness needed for proper expansion. I dont know the “science” behind the 1279.8

20,000 psi / 1279.8 = 15.62 bullet hardness

Now as far as magnun loads go. I have found with 357 plain base cast bullets just dont group well at magnum velocities for me. I dont get leading.
If I where to load magnum loads in 41mag I think I would just stick with hitek coated or FMJ
 
I haven't seen much in the way of jacketed stuff for .38 going past 1200 or so. Maybe really light bullets like 85 gr, but a lot of the common stuff like jacketed 125's and 158 rarely make it over 1100.

9 I don't load because honestly its still relatively inexpensive to buy.
Using Fed 155 gr syntec and Fed 115 fmj as a side-by-side, there isn't a big difference in listed velocity.

I have seen some .357 hardcast data at around 1500, non gas checked. Might be in a lymans book.



The general rule of thumb is to just use any published load data like from Hodgdon or anywhere else. I'm not saying its the be-all end-all for load data but its a good start.
You can get a little bit more out of coated because of less friction, and plated will go a little faster.

I don't necessarily think the issue is leading,although it is a factor because you can mix all kinds of lead together to get a specific hardness or coat it/ plate it. I think the issue is once you reach a certain velocity, anything past that and the bullet starts to pull itself apart due to centrifugal force. Soft metal can only spin so fast, I think the jacket keeps it from doing that.
Now I wouldn't try pushing straight lead, but even the mixed stuff with a brinnel hardness of 18 or better has a breaking point.

Gas checks I've only really seen for-

Carbine rifle data
Heavy/ compressed mag loads using a fast powder. - Even some of the lead-loads on the site list non-gas checked up to about 1500 or so with 180's

I have pushed some heavy stuff without gas checks. It might be powder dependent? Could be gr weight thats a factor?
A 180 gr .357 doesn't have the same amount of displacement and bearing surface than a 400 gr 45/70, so I'm sure theres some kind of "white man magic smoke-stick' math that determines what needs a gas check and what doesn't.

The above info may help or hinder.
The twist in all of those cartridges will keep you well under the RPM threshold.

You really needs to worry about it when. Getting into the single digit twists for sure. Anything over subsonic and you need to start using some magic to get it working
 
The twist rates in pistols should not get your bullets rpm so fast that your bullets go poof .

The twist in all of those cartridges will keep you well under the RPM threshold.

You really needs to worry about it when. Getting into the single digit twists for sure. Anything over subsonic and you need to start using some magic to get it working

I thought about that once a long time ago.
So the barrel acts as a cage, kind of retaining everything in a specific shape.
Also while in the barrel, it retains a specific r.p.m..

Would rpm's not increase with magnum loads once it leaves the barrel and is "uncaged"? Ballon out if its plated or coated lead, without a copper jacket to keep it in check?
 
I thought about that once a long time ago.
So the barrel acts as a cage, kind of retaining everything in a specific shape.
Also while in the barrel, it retains a specific r.p.m..

Would rpm's not increase with magnum loads once it leaves the barrel and is "uncaged"? Ballon out if its plated or coated lead, without a copper jacket to keep it in check?
If you get enough RPMs you’ll tear a bullet apart.
Not sure about anything ballooning out though. I mean it makes sense. If there’s enough force to rip a cast bullet apart there must be some beginning point where it starts to yield without blowing up.
 
I thought about that once a long time ago.
So the barrel acts as a cage, kind of retaining everything in a specific shape.
Also while in the barrel, it retains a specific r.p.m..

Would rpm's not increase with magnum loads once it leaves the barrel and is "uncaged"? Ballon out if its plated or coated lead, without a copper jacket to keep it in check?
It could ? What twist on you pistol

Im going to guess around 1/18

At that rate your not going to teach velocities to get up and past the threashold of cast bullets which is 120,000-140,000 rpm formula is
720 x Muzzle velocity / twist

You going deep into 2XXX fps before you have to worry.

If your looking to shoot cast theres. More info here than you can use!
From Ingot to Target: A Cast Bullet Guide For Handgunners, Table of Contents - Fryxell/Applegate
 
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Wow guys, this is great. There is alot for me to decipher and digest, but that is part of the reason I wanted to reload.... to learn something.

The .41 Rem mag in question is a (IIRC) 1984 Ruger Redhawk with a 7 1/2" barrel. As far as I can tell it has a 1-in-20 twist.

It seems the 1st thing I need to do is obtain 7 or more lead balls in .411, .412 or larger? Is that something I find in the black powder realm?

At least now I know why some of those cast bullet companies will size your bullets for you. I have about 300 cast bullets I think were sized to .410 - I guess ok to run in lower velocities?

Next I gotta do math. No chrono for now so I'll have to rely on published muzzle velocities. I hope that is going to be close enough to start.
 
Wow guys, this is great. There is alot for me to decipher and digest, but that is part of the reason I wanted to reload.... to learn something.

The .41 Rem mag in question is a (IIRC) 1984 Ruger Redhawk with a 7 1/2" barrel. As far as I can tell it has a 1-in-20 twist.

It seems the 1st thing I need to do is obtain 7 or more lead balls in .411, .412 or larger? Is that something I find in the black powder realm?

At least now I know why some of those cast bullet companies will size your bullets for you. I have about 300 cast bullets I think were sized to .410 - I guess ok to run in lower velocities?

Next I gotta do math. No chrono for now so I'll have to rely on published muzzle velocities. I hope that is going to be close enough to start

Yes black powder realm. A 45 round ball will squish down fine. You actually want to be way oversized so when you push it down the bore you have some decent flat spots to measure off of

You’re in Wareham? If you can wait a couple days I can cast up some pure lead round balls for you to slug your bore with.
I don’t cast or load for .41 but I can toss you a few 38 bullets to try.

Are you planning on attending the cast bullet seminar in the fall?
 
Yes I am right down rte 195 a couple miles. A couple balls would be great, and maybe bending your ear with a couple more ??? I am not in a hurry for anything, although at my ever advancing age maybe I should be.

I would like to attend

Thanks
 
Yes I am right down rte 195 a couple miles. A couple balls would be great, and maybe bending your ear with a couple more ??? I am not in a hurry for anything, although at my ever advancing age maybe I should be.

I would like to attend

Thanks
Sweet I can make that happen. I’ll get something together this week or if I can find some swaged round balls I’ll bring those to save time.

You would love the seminar. Anyone into the why behind all of this enjoys it. Even if you’re not going to deep dive it’s worth the price for lunch and the good people that go there.
 
Wow guys, this is great. There is alot for me to decipher and digest, but that is part of the reason I wanted to reload.... to learn something.

The .41 Rem mag in question is a (IIRC) 1984 Ruger Redhawk with a 7 1/2" barrel. As far as I can tell it has a 1-in-20 twist.

It seems the 1st thing I need to do is obtain 7 or more lead balls in .411, .412 or larger? Is that something I find in the black powder realm?

At least now I know why some of those cast bullet companies will size your bullets for you. I have about 300 cast bullets I think were sized to .410 - I guess ok to run in lower velocities?

Next I gotta do math. No chrono for now so I'll have to rely on published muzzle velocities. I hope that is going to be close enough to start.
Try to research elmer kieth and the 41 mag , its his child and he did a lot of bullet and load testing. So much so he has his own mold designs
Castboolits.com has a lot of info and sources.
 
As others have already stated fit is key. Iv got one 44mag that runs well with a .4325. When I first started reloading my own 45 colts and 44 mags I wanted full house loads all the time, kid thing. At the time I was using a MO. Bullet w a 18 brinell. A few years went on and I dropped to actual pleasant load and went to 12 brinell. Long strong short proper hardness and size are important. Burn rates are something to consider as well. One of the other fellas mentioned this. I wouldn't want to push mag velocity w titegoup. Much better with a slow lower pressure curve i believe.
 
Try to research elmer kieth and the 41 mag , its his child and he did a lot of bullet and load testing. So much so he has his own mold designs
Castboolits.com has a lot of info and sources.
I have read a little about Keith, I know that he is responsible for not only the 41, but also the 357 and 44 magnums. I knew he had a slew of wildcat rifle cartridges under his belt, Just rear alittle more --- didn't know he helped develope the Winchester model 70. He belongs on the Mt Rushmore of American firearm pioneers, right next to John Browning.
 
As others have already stated fit is key. Iv got one 44mag that runs well with a .4325. When I first started reloading my own 45 colts and 44 mags I wanted full house loads all the time, kid thing. At the time I was using a MO. Bullet w a 18 brinell. A few years went on and I dropped to actual pleasant load and went to 12 brinell. Long strong short proper hardness and size are important. Burn rates are something to consider as well. One of the other fellas mentioned this. I wouldn't want to push mag velocity w titegoup. Much better with a slow lower pressure curve i believe.
I have used True Blue for a comfortable round with success. For real magnum loads I do have a number of powders to experiment with - 2400, Enforcer, 110, 296 and maybe Accurate 9. For the hardness end of things i guess I'll have to go to bullet casting school🏫🏫
 
True Blue is a nice powder for that application I used to run that in 44, 38, 357 and 45colt. Iv used 2400 and #9 in a rifle with great results. Eventually I want to run some of that newer AA #11FS it develops some really hot velocity with lower PSI. I know Lil Gun does this to but they had issues with strap cutting.
 
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