Cast Bullets - Developing a load? [Archive] - Glock Talk

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CarryTexas
08-15-2012, 14:51
I am new to reloading and recently tested my first batches of .40S&W, .44MAG & .223.

In order to develop my loads for the jacketed bullets I chrono’d some factory rounds with similar characteristics. As an example:

Federal 155 grain HST JHP compared to my reloaded Hornady 155 Grain XTP JHP

I determined that the factory Federal round had a velocity of approximately 1150FPS at 10 feet. Once I had that as a benchmark I chrono’d increasing powder charges while checking cases for signs of pressure.

I was able to use this for my jacketed bullets, but I do want to save money and shoot cast bullets for plinking…

I have read that too little of a charge will prevent the base of the bullet from expanding and providing a good seal in the barrel and too much will cause the gases to melt the lead and cause leading…

Obviously, for the cast rounds I am not going the try to match jacketed performance.

However, How do you find the best charge weight for a cast bullet? I am primarily interested in .40S&W and eventually .45ACP

I am using W231 and Unique (Probably will settle on W231)

Three-Five-Seven
08-15-2012, 15:05
Velocity and pressure do not, necessarily, co-vary. In other words, matching velocity does not mean you're working in safe pressure ranges. Stop doing that!

Hodgdon's website lists cast bullet loads for a wide range of calibers. They are, after all, the CAS specialists in the field of reloading.

Lyman makes a specific manual for cast bullet loads, and has for over thirty years. It is a very authoritative source.

The Speer loading manual has several special sections on lead bullet loads.

And, the best shooting website on the planet is CastBullets. Those guys will always help you when the above named sources fall short.

Zombie Steve
08-15-2012, 15:17
Agreed - stop chasing velocity. If you're using a fast burning powder and trying to push it to factory levels, you could be in trouble quickly. Aside from the pressure danger of how you're approaching things, it's entirely possible that your gun won't like the load.

Find a suitable powder, find data, start at the start and incrementally step it up until you max out at the max. :supergrin: Sometimes the most accurate load is on the low end, sometimes on the high end.

Lead bullets in handguns can be driven every bit as hard as jacketed bullets, but they use different data.

I've found Lyman 49 to be very helpful with lead bullets.

CarryTexas
08-15-2012, 15:28
I guess I should have been more clear.

I set the velocity as a target and monitored for signs of pressure. I wasn't able to achieve the velocity before I started seeing signs of pressure.

I was able to get to 1080fps (7.4 Grains of Unique) without signs of over-pressure.

At 7.6 grains I was at 1120fps, but the primer was just starting to flatten out.

I do have Lyman #49, but it doesn't have the 155 GR Cast bullet. Only a 150 GR.

I will look into the other resources mentioned.

ColoCG
08-15-2012, 17:08
What good does it do to have a reloading manual like the Lyman #49 when you don't pay attention to it. While you were working up your 155gr. load to 7.6gr. of unique you might have noticed that the Lyman manual maxes out at 6.5gr. of Unique with a similar bullet. That's where loading to velocity can get you in trouble.

By the way it is hard to beat Unique for cast bullet loads.

You can always start out with a starting load that is listed in the Lyman manual for a heavier cast bullet and work up slowly.

Good Luck.

CarryTexas
08-15-2012, 17:31
What good does it do to have a reloading manual like the Lyman #49 when you don't pay attention to it. While you were working up your 155gr. load to 7.6gr. of unique you might have noticed that the Lyman manual maxes out at 6.5gr. of Unique with a similar bullet. That's where loading to velocity can get you in trouble.

By the way it is hard to beat Unique for cast bullet loads.

You can always start out with a starting load that is listed in the Lyman manual for a heavier cast bullet and work up slowly.

Good Luck.

Alliant's data has the 155gr. Jhp at 8gr. of unique. I started at 5.8gr and worked up from there.

fredj338
08-15-2012, 18:31
I am new to reloading and recently tested my first batches of .40S&W, .44MAG & .223.

In order to develop my loads for the jacketed bullets I chrono’d some factory rounds with similar characteristics. As an example:

Federal 155 grain HST JHP compared to my reloaded Hornady 155 Grain XTP JHP

I determined that the factory Federal round had a velocity of approximately 1150FPS at 10 feet. Once I had that as a benchmark I chrono’d increasing powder charges while checking cases for signs of pressure.


I have read that too little of a charge will prevent the base of the bullet from expanding and providing a good seal in the barrel and too much will cause the gases to melt the lead and cause leading…

Obviously, for the cast rounds I am not going the try to match jacketed performance.

However, How do you find the best charge weight for a cast bullet? I am primarily interested in .40S&W and eventually .45ACP

I am using W231 and Unique (Probably will settle on W231)
This is an extremely dangerous way to work up a load unless you understand pressures & powder burn rates. In some ammo, it's just not possible to reach facotry vel w/ canister powders. So you need to tread lightly w/ that approach, very lighty.
Lead bullets typ need less powder to reach the same vel & pressures. My theory; the bullets are larger in dia & more maleable so seal the bore better giving higher pressures & increased vel. Some say it's because they have less friction, but not true. Less friction would decrease vel & pressure, so not buying that one.
You may or may not be able to get a lead bullet to shoot well @ jacketed vel. A lot of things come into play like bullet fit, alloy composition & bullet lube. You are pushing W231 hard to get factory equiv 40 gvel w/ any bullet wt IMO. Unique is a better choice & PP probably better still. For higher pressures, harder bullet, sized properly & pushed by a a med to med slow burner can do quite well to 1300fps or more, but it isn't plug & play.

WiskyT
08-15-2012, 20:18
I also wouldn't trust chrono readings at 10 feet. Blast effects chrono and different powders have different blasts. So, your factory ammo chronos at say 1100fps at 10 feet. You make up a load with Unique, which is not used in your factory load, and it should be 1100fps. But, since you might be too close to the chrono, it only reads 975 while it is really doing 1150. So you add more powder based on possibly false chrono readings. Move the chrono out to 20 feet to eliminate any inaccuracies due to blast.

I don't see anything wrong in using a chrono to work up a load as long as you don't exceed published charge weights. Generally speaking, with Unique, I am able to duplicate factory velocity without even getting to max loads in several pistol calibers using cast bullets. 231 on the other hand always gave me leading and terrible accuracy when used any higher than start data.

ColoCG
08-15-2012, 21:39
Alliant's data has the 155gr. Jhp at 8gr. of unique. I started at 5.8gr and worked up from there.

I am well aware that in this instance that Lymans data is very conservative. But since you stated that you were new to reloading and had the Lyman manual I thought that was the only source you were using beside velocity.

That's why you need to use at least 3 sources of data. One can be very conservative while another can be very aggressive. A third source of data can be used along with the others to extrapolate what would be a good startining load and where you might want to work to.

Using factory velocities and working up velocities with a load with random powders is not the way to accomplish this safely.

Gunnut 45/454
08-15-2012, 22:29
fredj338
Well after 30 years of shooting lead bullets I find it take less powder to get higher velocity's with cast. And certain powders are better suited to cast bullets then others.
Lymans cast bullet reloading manual is an excellant source for proven powders for cast.
If you can't use or find the exact bullet type - find the one closest to your bullet and work up a charge = this is why folks need to have a chrony when reloading. He should be able to get with a few fps of factory rounds safely.:supergrin:

freakshow10mm
08-15-2012, 22:56
Lymans cast bullet reloading manual is an excellant source for proven powders for cast.
My only issue is they don't give WSF the credit it deserves.

freakshow10mm
08-15-2012, 22:57
I've found Lyman 49 to be very helpful with lead bullets.
Is 49 that much of an update/improvement over 48 to warrant its purchase? I've still been working off 48.

fredj338
08-15-2012, 23:08
fredj338
Well after 30 years of shooting lead bullets I find it take less powder to get higher velocity's with cast. And certain powders are better suited to cast bullets then others.
Lymans cast bullet reloading manual is an excellant source for proven powders for cast.
If you can't use or find the exact bullet type - find the one closest to your bullet and work up a charge = this is why folks need to have a chrony when reloading. He should be able to get with a few fps of factory rounds safely.:supergrin:

I think I said all that, so we agree. My point, plugging in more powder to achieve a factory vel is dangerous if you do NOT understand pressures & burn rates & their affects. The OP appears not to or he wouldn't be working up loads that way.
A chrono is a great tool, but like any tool, you have to understand how & why it works. I could easily KB a gun trying to reach factory 40 vel using powders like Clays or RedDot or sim uberfast.