Long Range Hunting Online Magazine

Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Rifles, Bullets, Barrels & Ballistics

Rifles, Bullets, Barrels & Ballistics Applied Ballistics


Help with BC calculation

LinkBack Thread Tools Display Modes
Unread 08-20-2004, 01:55 PM
Silver Member
Join Date: Sep 2002
Location: Nebraska
Posts: 313
Re: Help with BC calculation


Off of Hornady's website they say the 140 has a B.C. of .520. Running your numberson infinity with a 180yard zero with a b.c. of .7 i get
800-15.1 moa

With a 100yard zero with a B.C. of .82 i get


As one said seems to match the 300 and the 800 moa's but seems to fly flatter in the middle with your come up's.

Interesting and hopefully will report back.
Reply With Quote

Unread 08-20-2004, 03:32 PM
Writers Guild
Join Date: Jul 2001
Posts: 1,459
Re: Help with BC calculation

Matt, love to hear how you make out. I also found that 2750fps was a good vel for the 260Rem and 140gr bullets.

I hope that you will be able to get a 100yd zero the same for both bullets then compare the drop out to 1000yds. Measure muzzle vel for both so that a fair comparison can be made.

Good shooting...

Reply With Quote
Unread 08-23-2004, 06:34 PM
Platinum Member
Join Date: Mar 2003
Location: Southern Wisconsin
Posts: 1,381
Re: Help with BC calculation

You posted that you were using 58.5 grs of H4831sc in an '06 case, is that correct? The reason I ask is because that's nearly 9 grs. over the listed max in the Hornady manual for the 140 sst. They list their vel. at 2800fps for 49.4 grs of H4831, I would think 58.5 grs would be clipping along at more than 2975 fps.

Just curious

P.S. I'm curious enough that I ordered 2 boxes to try in my 6.5-284.
Ignorance can be treated with education, sadly there is no cure for stupidity.
Reply With Quote
Unread 08-24-2004, 10:54 AM
Writers Guild
Join Date: Jul 2001
Posts: 1,459
Re: Help with BC calculation

Yes, that is the correct load and yes, it is toasty. I know it is not above the vel I have listed simply because of comparisons to other 'sister' cartridges - 25-06 and 270win. Plus my chronograph has been used to measure other rifles and are ok.

The loads listed in the Hornady and Nosler manuals have a much lower pressure then is achieveable. They are using the '06 limits, not the 270/magnum limits.

I am loading to the 270 pressure levels and getting similar vel when comparing relative bullet weights and powder consumption.

The rifle only has a 24" barrel. I am not going to exceed 264 ballistics using a shorter barrel and a lot less powder. Pressures are at 270/magnum not insane levels.

Let us know how your testing turns out.

Reply With Quote


Thread Tools
Display Modes

Similar Threads for: Help with BC calculation
Thread Thread Starter Forum Replies Last Post
Ballistics calculation gregf Rifles, Bullets, Barrels & Ballistics 3 12-31-2010 12:36 PM
Cant angle calculation Topshot Long Range Hunting & Shooting 10 05-02-2009 02:49 PM
Ballistic Calculation Help! Rifles, Bullets, Barrels & Ballistics 8 08-19-2004 02:25 PM
Windage Calculation? LDO The Basics, Starting Out 3 02-28-2004 12:55 AM
Calculation of B.C. sscoyote Rifles, Bullets, Barrels & Ballistics 2 07-17-2003 09:54 AM

All times are GMT -5. The time now is 02:56 PM.

Powered by vBulletin ©2000 - 2016, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2015 Long Range Hunting, LLC