The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Reply
 
Thread Tools Search this Thread
Old July 13, 2007, 07:56 AM   #1
Dannyboy303
Senior Member
 
Join Date: February 27, 2007
Location: QLD, Australia
Posts: 116
Flattest Projectile for 30cal

Hey guys ive been doing some 1000yard shooting and im wondering your opinions on what the flatest shooting projectile for handloading a 300win mag is out to 1000yards? ive just been using 165gr nosler ballistic tips and they're dropping alot more than 27MOA
Dannyboy303 is offline  
Old July 13, 2007, 08:18 AM   #2
fisherman66
Senior Member
 
Join Date: August 22, 2005
Location: The Woodlands TX
Posts: 4,678
Why is flat important? I'd go with the best BC and a good tracking scope. I'd be more worried about wind drift than trajectory (which is predictable).
__________________
la plus belle des ruses du diable est de vous persuader qu'il n'existe pas!
fisherman66 is offline  
Old July 13, 2007, 09:23 AM   #3
Mike Irwin
Staff
 
Join Date: April 13, 2000
Location: Northern Virginia
Posts: 41,374
Flat trajectory is mainly a function of BC and velocity.
__________________
"The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza

Baby Jesus cries when the fat redneck doesn't have military-grade firepower.
Mike Irwin is offline  
Old July 13, 2007, 09:34 AM   #4
rwilson452
Senior Member
 
Join Date: June 10, 2004
Location: Tioga co. PA
Posts: 2,647
At 1000 yards you are problebly going to go transonic at some point you need a bullet that stays stable in that area. In a .308 bullet I would suggest the Sierra 175 gr HPBT Matchking bullet #2275
rwilson452 is offline  
Old July 13, 2007, 09:48 AM   #5
rgitzlaff
Senior Member
 
Join Date: January 8, 2006
Location: Madison, WI
Posts: 524
.300 win mag

He says he's shooting a 300 win mag, so he should probably be using something in the 200+ grain range. 175 is good for 308, but with a 300 wm you can use heavier stuff.
rgitzlaff is offline  
Old July 13, 2007, 12:41 PM   #6
Unclenick
Staff
 
Join Date: March 4, 2005
Location: Ohio
Posts: 21,020
Highest B.C. that will stay supersonic to 1000 yards with your loads will, by definition experience the least wind drift. Wind drift is proportional to the difference in time it takes for the bullet to hit the target and the time it would take to get there in a vacuum, with no air resistance slowing it. The higher the B.C., the slower the velocity loss. Unless you stay with one bullet weight, the best bullet choice may not be the flattest shooter. Many high B.C. bullets get their high B.C. partly from having high sectional density, and not just from their shape. These are heavy and start out too slowly to shoot flattest. They will, however, have very predictable elevation drop. The only reason I can think for wanting flatter shooting (light, high BC bullet like the Scenar 155 grain Palma bullet), is if you are using a scope and don't want to go to the long range scope ring bases with 20 m.o.a. added elevation built in. You can, however, get higher B.C.s in heavier bullets, but they may require the long range scope ring bases to stay within your scope's adjustment range.

As to the 27 m.o.a. drop, I am assuming you are getting that from a computer ballistics program. The G1 B.C. does not fit most high B.C. bullets very well, which is why you see them changed for different velocity ranges. That is a kluge, as the right B.C. fit will need only one number for all velocities. The error from the kluge fix tends to get worse at longer range. You need to work either with ballistic tables taken from measurements of your actual bullet, or to get software, like the RSI Ballistics lab, that will let you determine the correct B.C. for your bullet shape, be it G7 or G5 or whatever. The best fit B.C. type number may be lower than the G1 number, but the function will match your bullet much better and give you far more accurate velocity loss and drop and wind deflection predictions at long range.
__________________
Gunsite Orange Hat Family Member
CMP Certified GSM Master Instructor
NRA Certified Rifle Instructor
NRA Benefactor Member and Golden Eagle
Unclenick is online now  
Old July 13, 2007, 02:22 PM   #7
Scorch
Senior Member
 
Join Date: February 13, 2006
Location: Washington state
Posts: 15,248
For a 300 WM, I would choose the heaviest bullet you can launch with the highest BC. Hornady makes the A-Max in 178 gr or 208 gr. Figure out how fast you can launch then go to http://www.eskimo.com/~jbm/calculati...culations.html
to see your trajectory adjustments in MOA and velocity.
__________________
Never try to educate someone who resists knowledge at all costs.
But what do I know?
Summit Arms Services
Scorch is offline  
Old July 13, 2007, 08:45 PM   #8
crowbeaner
Senior Member
 
Join Date: June 4, 2007
Location: Upstate SC
Posts: 1,943
I believe that the AMU shooters that are using the .300 WM are using the 200 gr. Sierra MK. They know what works if anyone does. I stick to the 180 gr. Sierra in my 30/06 for long {over 400 yds.} range, but that's just me.
crowbeaner is offline  
Old July 13, 2007, 10:05 PM   #9
brickeyee
Senior Member
 
Join Date: December 29, 2004
Posts: 3,351
"Flatest shooting" makes no difference at known range.
brickeyee is offline  
Old July 13, 2007, 10:29 PM   #10
Trapper L
Senior Member
 
Join Date: November 20, 2006
Location: South Texas
Posts: 804
I'm shooting a custom 190 gr HPBT at 2700'ps muzzle and the MOA is 36.6. The 27 moa looks too ambitious to me. I would suggest a heavier bullet. And most of the folks in the winners circle are shooting either custom bullets or the Sierra Match Kings in 190 gr or heavier.
Trapper L is offline  
Old July 14, 2007, 10:59 PM   #11
Dannyboy303
Senior Member
 
Join Date: February 27, 2007
Location: QLD, Australia
Posts: 116
Quote:
"Flatest shooting" makes no difference at known range.
You're exacly right. i failed to mention that my scope only has 29MOA of adjustment and i was wondering if there is a projectile capable of dropping less than that at 1000yards. (according to jbm calculator the noslers i was using should have been 27moa but they were dropping far more than that.)

Thanks for the info i will get a box of each projectile mentioned and try em out.
Dannyboy303 is offline  
Old July 15, 2007, 12:48 AM   #12
amamnn
Senior Member
 
Join Date: May 13, 2006
Location: WA, the left armpit of the USA
Posts: 1,323
Accurate shooting at 1000 yards is a lot more involved than possibly you might think. A couple of places to find good information on the subject would be articles at www.benchrest.com and www.6mmbr.com. I say articles because lately there seems to be a great number of posts on the forums there from wannabes or others who have no real experience actually shooting but a do have lot of typing skills.
__________________
"If the enemy is in range, so are you." - Infantry Journal
amamnn is offline  
Old July 15, 2007, 06:51 PM   #13
brickeyee
Senior Member
 
Join Date: December 29, 2004
Posts: 3,351
"i failed to mention that my scope only has 29MOA of adjustment..."

Get a base(s) that has some rise built in.
brickeyee is offline  
Old July 16, 2007, 06:51 AM   #14
Dannyboy303
Senior Member
 
Join Date: February 27, 2007
Location: QLD, Australia
Posts: 116
Cheers guys great help as always.

Good sites amamnn, well benchrest anyway the other is under maintainance.

Good idea about the mounts brickeyee i hadent thought of that, i figured that if i 0 at 100yards with scope at its lowest point i can get 70MOA of adjustment which is alot better. i know i wont get it to the lowest dial with a zero but i'll get close because dad is a fitter he can always make an extension on the base to suit. even 40MOA would be great
Dannyboy303 is offline  
Old July 16, 2007, 12:09 PM   #15
brickeyee
Senior Member
 
Join Date: December 29, 2004
Posts: 3,351
Many scopes are not at their best when set near the limits.
Both optically and mechanically they often have problems outside about the middle 50% of the adjustment range.
brickeyee is offline  
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 09:59 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2021 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Page generated in 0.09331 seconds with 10 queries