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View Full Version : Can anyone help with ballistics of this load, please .30XCB



kens
01-15-2020, 06:18 PM
Hi,
I am working with a muzzleloader based on a .32-40 barrel blank. it is breeched a muzzleloader. bore/groove is 314/321 1:14 twist.
The bullet I got is a oversize 30XCB mold dropping at 314, soft lead, flat based, lubing with LBT Blue, 179gr lubed,
Loading with 40gr FFFg. 50yard zero, and 1300fps at muzzle (chronographed)
Went out to 100yards and got 2" drop.

Can anyone help me with the longer range ballistics?
Is this enough data to put into a ballistic program and get downrange trajectory?
Especially the subsonic data. I expect this to go transonic around 150yds.
I hope to go out to 200, 300, 400 yards, and would like some elevation data to begin with.

My scope is a Unertl clone, Litschert 10x, it got the external adjustments and Unertl mounts.
Thanks,

shortlegs
01-15-2020, 09:53 PM
Look up ballistics calculator. Hornady has one that is easy to use.

Ford SD
01-15-2020, 11:57 PM
The Bc of the 30xcb is .286

if yours is fatter it would be a lower number .27 ??? close ??

kens
01-16-2020, 08:35 AM
thanks, I tried the Hornady calculator, I put in all the data, and it told me I need come up 4" but at the range I only come up 2" in reality.(from 50yd to 100yd)
I'm only needing this as to not spray bullets all over the place and maybe miss the berm, as I move out to longer ranges.
My big issue is we do not have a 150yd range.
We got 100yd, 100m, then the ranges go up to 200-300-400-500yard berm.
there is no 150yd berm.
if I was assured how big a target backer I need to crank my sight in i'll be fine.

Larry Gibson
01-16-2020, 11:36 AM
Center of scope above center of bore height is needed for accurate LR calculations with such(?).

Temp, humidity and barometric pressure would be helpful?

kens
01-16-2020, 11:52 AM
scope is 1.665" above bore
temp 80f
humidity 70%
30.15 baro
75ft above sea level
thanks

Harter66
01-16-2020, 08:39 PM
Ken's if you have a smart phone the free Strelok app has been very accurate for me with a very wide range of bullets and speeds . It can be set up to give 0-800 yd , drift/drop in mil , moa , in , metres , velocity , energy and time of flight .

Larry Gibson
01-16-2020, 09:06 PM
Click on it to enlarge

254923

charlie b
01-16-2020, 09:23 PM
I use the Nikon app on my phone. It has been very good at helping me predict drop for certain bullets. It also has a means to find a muzzle vel based on the drop between, eg, 100 and 200yd.