9 mm 124 gr cast with Unique??

P

PolarFBear

New member
Just made a batch, 750, 9 mm using a Lee 124 grain TL mold. Now, I need a powder charge of Unique. Looking for about 975 fps, nothing to fast. Something for 124 grain Berry's plated as well. I was thinking 4.3 grains. Suggestions???
 
Alliant uses 5.2-5.8 starting to maximum for a Gold Dot which has a plated jacket that is softer than a drawn jacket, but harder than Berry's, so you could probably run the Berry's starting at least to the starting load and maybe all the way to the top, watching for pressure signs and metal fouling and accuracy not getting suddenly wild. This is also assuming you use the same seating depth.

Seating Depth = Nominal Case Length + Bullet Length - COL

If you want to know the COL to target to achieve a particular seating depth you've learned for another bullet then just rearrange the above formula:

Target COL = Nominal Case Length + Bullet Length - Seating Depth

For the TL bullet, since I don't know your alloy hardness, figure to start where you suggested and to work up, using a chronograph, but not likely to exceed 5.2 grains. Again, this assumes same seating depth. Deteriorating accuracy or excessive leading are potential pressure signs, signalling you to back down.

After altering burn rate to get a velocity match with the Gold Dot data at Alliant, for which the seating depth appears to be 0.204", both cast and Ranier plated bullets hit 975 fps (4" barrel, as is standard for 9 mm testing) at 4.7 grains of Unique. So measure your bullet lengths and use the second formula, above, to give you a COL to try. If you have to seat deeper to fit and feed or pass the plunk test, then bring the powder down 0.1 grains for each 0.018" deeper you have to seat to stay at about 975 fps. From the 4" barrel, the pressure is less than 2/3 the Alliant maximum with this 975 fps load, so that simple increase in depth and change in powder charge don't change pressure enough to matter until you go more than about 0.18" deeper in seating depth.

The issue is going to be whether or not this light load will cycle your gun.
 
Your best bet would be to look up the data in Lyman's Cast Bullet Handbook, or Lyman's 50th. I have a "rule' for me that I suggest to anyone that will listen; I pay very little attention (None) to any load data from any forum expert, range rat, well meaning friend, gun counter clerk, pet loads website, or gun shop guru. I get all my starting load data from my published manuals and an occasional bit of data from powder manufacturer's websites and work up, keeping records of every load I assemble. I refer to my published manuals for maximum loads and watch for pressure "signs"...

30+ years, one squib (1970) and no kabooms... :rolleyes:

FWIW, for the 1,000 plated bullets I reloaded, I used lead bullet data and methods.
 
That is correct. You always double-check what you see on a site against published data, if for no other reason than we can make typos.

In this case, however, the only load Lyman has that is close is in their cast bullet manual and is for a 125 grain #356637 HP cast bullet seated to a very short 1.01 COL, and they recommend 4.5-5 grains of Unique, so we are in the ballpark here. But again, I can typo with the best of them, so you really should get that book and read it for yourself.
 
You have to work up the load for your pistol.
"...a Gold Dot which has a plated jacket..." You may want to re-read that. A GD is a jacketed bullet according to Speer. They speak of jacket separations. Plating doesn't do that.
 
For your velocity goal I'd load in the 4.5 to 4.8 grain range and no higher using unique and cci 500 primers.
 
T. O'Heir,

It is jacketed by electroplating. I got that from the horse's mouth. I spoke with a Speer technician who had personally run the plating process. He said it's important to know because there was some existing Gold Dot data that had starting loads higher than the maximum loads for some same-weight bullets with jackets drawn from formed cups.

I have no explanation for the separations, I'm just reporting what Speer told me. Plus, the lower starting pressure QuickLOAD's author found was needed to predict their behavior is further evidence the Speer technician was correct.
 
Thanks Unclenick. The Lyman book was my third.reference I checked. First was Lee's then Hornady. None listed a direct match with bullet and powder. So I deferred to the experts on the board.
 
No expert here, but I find Unique to push a coated lead bullet or heavy plated a little faster than I want to go. I do use it for some of my JHP loads.

For something in 975fps range I would look at w231/HP-38 or HS-6. I am on a CFE-pistol kick right now. I am pushing coated lead about 1100fps with good results.
 
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