The great converson...jacketed to lead

J

J.W.Proctor

Inactive
Having recently come into a large number of Accura plated bullets and learning that I should be using cast data for those loads instead of jacketed:o, I was wondering if there is an easy method for converting the data I see in books from jacketed to cast?
I.e. Reduce charge by 15% and workup from there or some thing like that:confused:the

I have a chronograph and am currently reloading 10mm and 9mm.
 
Accura has a website. Says max vel. on their pistol bullets is 1300 FPS. Using jacketed data, start low and work up as you would any bullet.
If you do use cast bullets, Lyman has a great cast book and a great pistol and revolver book.

I suggest you go to Accura's website and check it out.
 
Just get your data from a manual that supports lead bullets. You're going to get answers from those that load with lead data, jacketed data and a "formula" like "mid range jacketed data". I have only tried about 1,000 plated bullets (in 3 handguns) and used lead data, straight from Lyman's 50th and Cast Bullet Handbook...
 
My 9mm Minor loads with plated are slightly less than for jacketed of the same weight.
I don't think a "Starting Load" will be much different.
 
"...method for converting the data..." No such thing. Most manuals will have at least some cast bullet data. It may be in a separate chapter or it may be on the same pages as the jacketed data.
Keep in mind that the shape of a cast bullet doesn't matter. A 150 grain(just a number) RN and an SWC use the same data.
 
I would say if your a relatively new loader stick with lead data to be safe, can't go wrong there. If your a more experience loader I start at mid lead data levels and go up to mid jacketed data levels. In general my experience has been the best performance accuracy wise is usually found at the upper lead data to lower jacketed data levels. One criteria for me is not exceeding the recommended velocity of 1200 fps or in the case of the heavier coated type 1400 fps. Since I have matching carbine/ lever actions in all my handgun calibers I chrono the loads in the rifles not to exceed these velocities. I did load some X-treme 158gr RNFP's up to 1500fps in my .357mag Henry once and they shot very very nice out to 100yds. But, it took me about three days to clean the Cu out of the bore. Learned my lesson there. For general plinking/range shooting I love the X-treme bullets, but for the more stout loads the Berry's heavier plated bullets work very well for only a little more money.
 
J.W.Proctor said:
Having recently come into a large number of Accura plated bullets and learning that I should be using cast data for those loads instead of jacketed:o,
Click to expand...

Who told you that you needed to use cast data? Certainly not Accura....this from their website,
We have found that our bullets can be loaded with any jacketed load data found in most re-loading manuals and websites.
Click to expand...
 
reddog81 said:
T. O'Heir said:
Keep in mind that the shape of a cast bullet doesn't matter. A 150 grain(just a number) RN and an SWC use the same data.
Click to expand...
Reading any reloading manual would prove otherwise.
Click to expand...
So would me real world experience.

I load .45 ACP using Berry's plated, round nose 230-grain bullets. I started out using data that said I should be seeing around 830 fps. In reality I was getting in the mid 700s. I then stumbled onto a project they're running on the M1911.org forum to document differences in bullets, in order to address this very issue. If you seat to a known COAL but the bullet you use has a shorter body than the reference bullet, then obviously you're going to leave more volume behind the bullet -- resulting in lower pressure and lower velocity.

It turns out the Berry's 230-gr bullet is comparatively short compared to many jacketed 230-gr bullets.

The M1911.org project: https://forum.m1911.org/showthread.php?77249-Collecting-Dimensions-Bullet-Data

The actual data: https://docs.google.com/spreadsheet...uItM0glf7wjhd8/edit?hl=en&hl=en#gid=519572970

And a huge shout out to Niemi24s, the guy who compiled all that data.
 
J.W.Proctor said:
Good to know I defiantly thought that was a factor.I got the lynman book. Is the purpose of a 102 gr 9mm to save on lead?
Click to expand...
Yes ... Wheel weights are getting hard to find .
I actually used that data to develop a 9mm Luger load with the Lee 358-105-SWC (105 grains) bullet for a light recoiling load for a Walther P-38 of WWII vintage . I didn't want to batter the old war horse and the load shoots accurately to the P-38's sights and it feeds like a champ.
I was happy to see that data for the 102 grain bullet...gave me a reference point to start from.
Gary
 
You have to keep in mind a lube groove in a cast bullet adds to the length of a given bullet weight, so a 102-grain bullet is probably around the same length as a 115 grain jacketed bullet with the same nose form. Seating depth affects pressure, so avoiding having to seat too deeply helps with that.
 
You must log in or register to reply here.
Back
Top