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


Reply

7 WSM vs. 300WSM at 1000yds

 
LinkBack Thread Tools Display Modes
  #8  
Old 03-12-2004, 11:30 AM
Silver Member
 
Join Date: Jul 2003
Location: Texas
Posts: 149
Re: 7 WSM vs. 300WSM at 1000yds

Trader, the BC's for JLK bullets are as follows: 7mm-168gr= .690, 7mm-180gr=.738, 308-175gr =.545, 308-190gr =.602, 308-210gr =.665 This info came from Jimmy Knox of JLK bullets.
Reply With Quote
  #9  
Old 03-13-2004, 12:31 AM
Writers Guild
 
Join Date: Jul 2001
Posts: 1,459
Re: 7 WSM vs. 300WSM at 1000yds

From the guns that I have built and shot at 1KM, I would definitely go with the 7mm for these reasons.

If competing, weight and recoil will be issues so barrels can't be super long. Fatigue with the heavier bullet will affect groups. The WSM case is getting a bit small for real heavy 30cals. Perfect for the heavy 7mm.

Accuracy may not be at the vel level you need to make the 30cal 'work'. With the 7mm, even if it ends up being slower, the high BC will help at 1KM. Most barrels shoot their best at less then max pressures.

Compare the effects on a ballistic program. I bet you will find that BC plays a much larger role then vel when it comes to wind drift. drop is of little importance as you will know how far you are going. Misjudging the wind by a few MPH is pretty common and the higher BC bullet will shoot through those conditions better.

Jerry
Reply With Quote
  #10  
Old 03-13-2004, 10:09 AM
Bronze Member
 
Join Date: Feb 2004
Location: Wyoming
Posts: 84
Re: 7 WSM vs. 300WSM at 1000yds

BC is the controling factor in wind drift. If two bullets have the same BC they will drift exactly the same no matter what weight each bullet is.
__________________
John Burns
www.greybullprecision.com
Reply With Quote
  #11  
Old 05-04-2004, 08:51 AM
Silver Member
 
Join Date: Apr 2004
Location: Australia
Posts: 250
Re: 7 WSM vs. 300WSM at 1000yds

John has it right . BC is the important factor , not weight . Time of flight is also important . IF BC is the same then velocity will govern which bullet drifts (and drops) most .
Reply With Quote
  #12  
Old 05-04-2004, 08:17 PM
Bronze Member
 
Join Date: Sep 2003
Location: Huntsville, Al
Posts: 49
Re: 7 WSM vs. 300WSM at 1000yds

Boyd Heaten shot this same bullet for matches he pushed them around 2,800 and for hunting around 2,950, not sure about barrel length but I beleive it was about the same length as what you stated.
Reply With Quote
  #13  
Old 05-05-2004, 07:17 AM
Platinum Member
 
Join Date: Jun 2007
Location: Wilmington NC
Posts: 4,222
Re: 7 WSM vs. 300WSM at 1000yds

JD

I shoot the 300 WSM in HG and I can take a 210 JLK to around 2875 with good accuracy in a 30" Spencer barrel.

I am building a new 300 WSM with 30" Broughton barrel with the "5C rifling". It is the radiased lands like the Obermyer and Rock barrels. Broughton barrels are really kicking but lately and people are getting higher MV due to the rifling. This gun will be throated to shoot the 187 BIB flatbase bullets. Jim Hardy in NC is getting 3125 MV with 30 Broughton barrel in 300 WSM and Norma brass now and great accuracy.

This setup requires special long throat reamer as the bullet has pressure ring that must be in the neck.

Based strictly on the BC, the edge is to the 7MM WSM as I said before and I would look at the Broughton barrel with 1-9 twist if you want max MV and accuracy.

BH
Reply With Quote
  #14  
Old 05-06-2004, 04:06 AM
Silver Member
 
Join Date: Oct 2003
Location: Washington State
Posts: 120
Re: 7 WSM vs. 300WSM at 1000yds

This is what I am getting out of a 28" 1 in 9 Lilja 3 groove 7mm WSM:

Win LRM Primer
Berger 180 VLD
Win Cases
VV N165 Powder

Grs. Velocity(SD)

61.0 2737

61.5 2757(6)

62.0 2780 Group size: .313"@100 yards 5 shots.

62.5 2800

63.5 2858(10)

64.0 2890(15)

75.3*F
29.75 in Hg
49.7 RH

Looks like more investigation for accuracy only needs to be made for loads from 61.5 to 63.0 Initial indications are that rounds have very excellent consistency.

On a second occasion, we visited the range with 180 Berger VLD and VV N165 but with F215M, a magnum match primer:

62.0 2834(9)
62.5 2866(8)
63.0 2895(7)
63.5 2916(6) Group size: .401 @ 100 yards 5 shots.

85.0*F
30.2 in Hg
25% Humidity

Interesting in this case the best group was the heaviest load. Some minor primer extrusion around firing pin, nice bark, light to medium recoil even with Break and 15# gun.

With WLRM primer, best group was 62.0 to 62.5. This is an excellent mid-range target load.

I think for now the F215M load will be the one loaded for target shooting.

__________________
People slept peacefully in their beds at night only because rough men stood ready to do violence on their behalf. -- George Orwell
We honor and support those men and women who stand ready to do violence on behalf of the United States.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: 7 WSM vs. 300WSM at 1000yds
Thread Thread Starter Forum Replies Last Post
300wm to 1000yds bigsal5353 Long Range Scopes and Other Optics 5 02-24-2011 08:57 PM
30-06 to 1000yds Nomad Long Range Hunting & Shooting 25 07-10-2009 08:55 AM
.325 wsm at 1000yds? bellboy Rifles, Bullets, Barrels & Ballistics 16 12-09-2008 01:01 AM
308win. at 1000yds.? jester714 Varmint Hunting 14 01-02-2008 04:09 PM
Going for 1000yds Tonight lerch Long Range Hunting & Shooting 30 07-12-2005 08:22 AM


All times are GMT -5. The time now is 02:24 AM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC