Moving a load from Prime brass to LC (.223)

[TimK]

I had a great load developed in Prime brass for a JP AR in .223. I can't recall the exact charge weight, but on the order of 24g of TAC with 77g SMK's. It was a consistent 1/2 minute performer when loaded on a Dillon 1050.

I tried the same load in LC brass. It was actually more accurate by about 1/8"-1/4". Pretty damn good. It's slow now, though. Like 125 fps slow.

I measured case capacity, and the LC is showing about 2% more.

It shoots so well I won't be disappointed if I can't get the speed back, but I guess I'll try.

I'm open to all thoughts on the subject including any similar experiences. Specifically, I'm wondering how much more powder to try. 2% is roughly half a grain, so in the absence of other guidance I think I'd load some up in that area and see what's what.

 

[spife7980]

New brass = new load

You cant just add 2% powder and expect it to be the same, its not a linear relation ship, there are many more variables in play. Might be close, might be not at all.

 

[SkyScrapin]

While I agree with @spife7980 , you can bump up the charge weight to see if you get your velocity back up and maintain your accuracy without pressure signs. You'll never know unless you try.

 

[supercorndogs]

The two comments are not mutually exclusive. They are both telling you to work it up again, and working it up again is the only way to know.

 

[Milo 2.5]

What has been minimal work for me in the past is figure what pct of the case you are using now and transfer that over, usually be .1 or .2gr over-under.
But a 2% increase of 29gr not much, just add some powder and try it.

 

[TimK]

Yup, I'll give it a whack. I dislike load development, but it's gotta be done.