I just got a couple hundred Lyman 311334 197gr GC from Ed at Maplewood bullets. I’ve been scouring the InnaNet for the bullet’s B.C. so that I can take an educated guess at a 300 AAC BLK subsonic load trajectory. (Single shot; don’t need no stinkin’ gas port!) No luck…or my search skills suck. Would any of the cast bullet cognoscenti be willing to help me out? Thanks.

Can't speak to your need for BC but I'll comment that this mold is one of my all time favorites. It was one of Dr. Hudson's designs, along with 311331, 332, 333, and 335. Good medicine for Krags and Springfields. I'll be casting a hat full of 311332's this weekend, for use in a M1903A1 USMC Sniper.

This may give you a down and dirty quick rough idea.

https://gundata.org/ballistic-coefficient-calculator/

How can you trust this guy who says this??


No clue about casting but knows what info someone needs ?

This may help too if you have a chronograph and can math well.

Bat signal out to Mathman.

https://www.thetechedvocate.org/how-to-calculate-ballistic-coefficient-a-comprehensive-guide/

Holy Contributing to the Delinquency of Minors!
Holy Knit One, Purl Two!
Holy Cinderella!
Holy Priceless Collection of Etruscan Snoods!

Thanks to the respondents, but regretfully my math skills are not up to the suggested hands-on approach. I was thinking that perhaps the bullet’s B.C. was well known…just not by me.

Well, there is another way to get your ballistic arc.

Go shoot drops at several known distances, and record that data. Then input whatever it takes into JBM Simplified until you have a drop chart that matches whatever your real world drops are.

What's the max range that you expect to shoot these loads?

According to the Lyman Cast Bullet book #3, the BC of the #311334 is .340.

Thank you!