.243 bc

bigboodydaddy

Well-Known Member
I reload .243 with 100 gn spitzer spbt with n160 powder and there running at 2515 fps i have just purchased a hik alpex lrf scope the data requires the bullets bc to run correctly its spot on with the ballistic calculator off but when its on its way off any help would be greatly appreciated. Thanks
 
I reload .243 with 100 gn spitzer spbt with n160 powder and there running at 2515 fps i have just purchased a hik alpex lrf scope the data requires the bullets bc to run correctly its spot on with the ballistic calculator off but when its on its way off any help would be greatly appreciated. Thanks
Also, can I suggest checking the velocity too? 2515fps is pedestrian for a 243 Win and only giving you ~1400 ft-lb.
Regards
JCS
 
If you don't know the bullet type then try Sierra 100gr. It will probably be incorrect but muzzle velocity is more important at stalking ranges than bc so while it is good to be precise a decent approximation is ok
 
I reload .243 with 100 gn spitzer spbt with n160 powder and there running at 2515 fps i have just purchased a hik alpex lrf scope the data requires the bullets bc to run correctly its spot on with the ballistic calculator off but when its on its way off any help would be greatly appreciated. Thanks
You realise that is pretty slow for a 243 with 100 grain yeah?
 
Try changing your zero distance on the scope (not your physical distance).
Yesterday I was truing the data in Strelok for my 20 Tac. I have just acquired a Magneto speed. So I checked speed, and zero at 100yds. Moved target to 300yds, and checked drop vs the app. Moved zero out to 175 and data then tallies.
This advice came from a friend who went on a long range day with Richard Utting iirc. He was hitting small targets at 600+ with his 87vmax 243 load. The limit was the scope fitted meant he couldn’t see the longer range ones.
Seems to work once you have an accurate velocity and the bc.
Bear in mind that the scope assumes the bullet is dropping from your zero point. So if you have crossed at 100 on the way up. It will throw the data out.
 
Most 100gn bullets in 243 will do 2900 to 3000 fps depending on load, but that is quoted for a 24” barrel.

Depending on load, powder etc you can easily loose 50fps per 1” of barrel lost. Take a 243 down to an 18” barrel and 2500 to 2600 may be all velocity you are getting.

N160 is also quite a slow burning powder and especially in a short barrel you won’t be getting a complete powder burn and thus velocity will not be as good as it could be.
 
Back
Top