24hourcampfire.com
24hourcampfire.com
Previous Thread
Next Thread
Print Thread
Hop To
Joined: Sep 2006
Posts: 2,226
fremont Offline OP
Campfire Regular
OP Offline
Campfire Regular
Joined: Sep 2006
Posts: 2,226
I just loaded and shot some 129 Hornady IB's over Re-33 in my 264 WM, and, when I got home, I compared the actual chrono'd velocities to QL. To get an exact MV match, I had to lower the weighting factor to .39 (the QL instructions say an overbore bottleneck case would have a .33 default value).

Has anybody else adjusted QL for the 264WM?


Murphy was a grunt.
BP-B2

Joined: Dec 2004
Posts: 14,466
Campfire Outfitter
Offline
Campfire Outfitter
Joined: Dec 2004
Posts: 14,466
I don't understand why the weighting factors are not fixed as a part of the database for each cartridge...but they just aren't. I think that each cartridge will have a unique value for that field, and there's no way I can think of to determine what the real weighting factor should be. I do realize that if you lower the value, the program shows greater latitude in terms of charge weight. Whether or not the weighting factor should be .33, or .39, or whatever, anyone's guess is as good as another. I think the burn rate adjustment for the particular lot of powder you're using might be just as much a factor in matching up your QL solution and real results.


Don't be the darkness.

America will perish while those who should be standing guard are satisfying their lusts.


Joined: Sep 2006
Posts: 2,226
fremont Offline OP
Campfire Regular
OP Offline
Campfire Regular
Joined: Sep 2006
Posts: 2,226
Originally Posted by RiverRider
there's no way I can think of to determine what the real weighting factor should be.


I found one thread at another site where one guy did the following calculation to categorize how "overbore" a cartridge was.

Case capacity (grains in water) divided by Bore Area (pi times Bore Radius-squared).

So, when I apply that to the 264WM, I get a quotient = 1,526. When I tried it on a 30-378 Wby, I get a quotient = 1,693.

Then, he compared his overbore ranking to what QL listed as the default weighting factor that appears in QL for that particular cartridge. For the 264WM, I got = .50; for the 30-378 Wby, I got .52.

His overall conclusion seemed to be that he didn't feel like QL's default weighting factor always took the "overbore-ness" into consideration.

Interesting. YMMV

Last edited by fremont; 07/25/14.

Murphy was a grunt.

Moderated by  RickBin 

Link Copied to Clipboard
YB23

Who's Online Now
159 members (257 mag, 2UP, 10Glocks, 300jimmy, 01Foreman400, 10gaugeman, 13 invisible), 1,471 guests, and 829 robots.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums81
Topics1,187,590
Posts18,397,904
Members73,815
Most Online11,491
Jul 7th, 2023


 







Fish & Game Departments | Solunar Tables | Mission Statement | Privacy Policy | Contact Us | DMCA
Hunting | Fishing | Camping | Backpacking | Reloading | Campfire Forums | Gear Shop
Copyright © 2000-2024 24hourcampfire.com, Inc. All Rights Reserved.
Powered by UBB.threads™ PHP Forum Software 7.7.5
(Release build 20201027)
Responsive Width:

PHP: 7.3.33 Page Time: 0.121s Queries: 14 (0.003s) Memory: 0.7965 MB (Peak: 0.8294 MB) Data Comp: Zlib Server Time: 2024-03-28 09:46:52 UTC
Valid HTML 5 and Valid CSS