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

Group size at what range?

 
LinkBack Thread Tools Display Modes
  #22  
Old 10-05-2010, 03:44 PM
Official LRH Sponsor
 
Join Date: Jun 2004
Location: Fort Shaw, Montana
Posts: 6,822
Re: Group size at what range?

Mikecr,

Wow, Usually can follow your comments but that post was out there.

You attack my comment that group moa size will decrease as range increases and then at the end of your post you say most of your groups will decrease in moa size as you increase range........ WTH!!

Your right, I have no idea how to adjust my optics to elimiate paralax. Thanks for the heads up on that one!!! WOW!!

Also, I did not say it does not occur with lighter bullets in slow twist barrels but that it is instead easier to see and more dramatic in heavy for caliber, high BC bullets shot at high velocity in fast twist barrels. Again, you say its not possible but then say it happens to you all the time..... Plus, if your getting a 50 gr bullet at 3600 fps in a 223 Remington, you need to tone things back a bit my friend!!!, your about 200 fps over where you should be at most.

Yes groups do generally open up to some degree as the range increases but they certainly do not increase in size in porportion to the range they are being shot at. For example, a 1" group at 100 yards does not equate to a 4" group at 400 yards or an 8" group at 800 yards.

Sometimes the groups increase in size, even when measured in MOA but in a top quality rifle, this increase in size is generally caused by environmental conditions we are not judging accurately or us as shooters imposing our ill effects on the rifle. Which brings us back to my original point.

"UNTIL THE RIFLE IN QUESTION IS FIRED FROM A SOLID SHOOTING POSITION WE HAVE NO IDEA WHAT THE ACCURACY POTENTIAL OF THE RIFLE OR THE LOAD IS, SHOOTING FROM A SITTING POSITION WILL NOT GIVE EVEN THE FAINTEST IDEA WHAT THE RIFLE AND LOAD REALLY CAN DO AS FAR AS GROUP SIZE."
__________________
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com

allenmagnum@gmail.com
Reply With Quote
  #23  
Old 10-05-2010, 04:04 PM
Silver Member
 
Join Date: Dec 2009
Location: Boise, Idaho
Posts: 483
Re: Group size at what range?

I do have some 210 SMK's, I don't think I have given them enuff time yet. But with hunting season less then a week away and the weather is not the best for shooting. I noticed when measuring with a comparator that the barnes tipped triple shock bullets seat different then the A-Max bullets, they must have a different diameter Ogive. but overall length is still shorter then the A-Max rounds. Its all very interesting stuff and can be quite frustrating sometimes.
Reply With Quote
  #24  
Old 10-06-2010, 06:17 PM
Official LRH Sponsor
 
Join Date: Jun 2004
Location: Fort Shaw, Montana
Posts: 6,822
Re: Group size at what range?

Every bullet will have different OALs when they are seated to the same distance in relation to the origins of the lands. Thats why you need to reset your seating dies for each bullet and confirm distance from the lands.
__________________
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com

allenmagnum@gmail.com
Reply With Quote
  #25  
Old 10-06-2010, 10:54 PM
Gold Member
 
Join Date: Apr 2007
Location: ALASKA
Posts: 504
Re: Group size at what range?

Concepts that are difficult to absorb/understand are often put in the "witchcraft" category before we give them their due.

What if.......just what if......the progression of a accuracy/precision trend from a shorter range, to the results seen at a longer one was due to two components....

1st component....angular deflection of shot placement due to shooter/load error will continue to be manifested in a linear function at distance. i.e. I yank a shot one MOA/MIL left at 200 yards, it will now be two MOA/MIL left at 400, and six MOA/MIL left at 600, and so on....

the 2nd component...Lack of accuracy/precision due to the bullet "not going to sleep"....hmmmmm.....it doesn't seem any of our longer/higher BC projectiles are immediately stabilized in terms of pitch/yaw by the model below....

So...it would seem if one had a very precise rifle, and was an outstanding marksman, firmly grasp the fundamentals of shooting a rifle, and had consistent/precise ammunition, to minimize the effects of the first component listed above, that Kirby's results (and others) results might very well be plausible, and even accounted for by ballistic models.....

My dumbest day will be the day I'm too smart to learn....

Good luck and keep it fun! Go shoot at long range!

Reply With Quote
  #26  
Old 10-07-2010, 05:42 PM
Platinum Member
 
Join Date: Aug 2003
Location: NC, oceanfront
Posts: 3,331
Re: Group size at what range?

The epicyclic swerve affects above & tested by Berger, amount to corkscrewing flight well under 0.1" within 3-5yds. This anomaly in flight is damped toward unmeasurable by 100yds, even in an extreme.

There is an investigation into both opening and closing dispersions in chapter 11 of APPLIED BALLISTICS FOR LONG RANGE SHOOTING. Everything related to this thread, including my implications, is well investigated there.

Last edited by Mikecr; 10-07-2010 at 05:48 PM.
Reply With Quote
  #27  
Old 02-14-2011, 06:00 AM
Bronze Member
 
Join Date: Feb 2010
Location: just east of memphis, tn
Posts: 61
Re: Group size at what range?

Ok... Back to the original question... As was stated earlier load development should be done from a bench or from your belly with bag and bipod. That said I had a similar issue with 168 bergers and my 300 wsm. They shot 1/4 to 1/3 moa at 100 yds but at 300 they wouldn't hold 1 moa. Tried190's and got down to 1/2 moa at 100. Stepped back to 300 and again couldn't hold 1 moa. Tried their 185 target bt and got sub 1/2 moa at 100 moved back and 1.8" at 300. Unfortunately I was told the jacket was too thick to hunt with this bullet. However being pressed for time I hunted this yr with that load anyway and limited my range. I am about to try something else although I hate to given the accuracy of this load. ( recently shot a .65 @ 200 yds from my belly)
Oh well
Reply With Quote
  #28  
Old 02-14-2011, 07:55 PM
Gold Member
 
Join Date: Mar 2006
Posts: 848
Re: Group size at what range?

Interesting discussion.
At 565 yds I will work up a load that shoots 3 shots into 1.5-1.75 inches, with as little vertical dispersion as possible.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: Group size at what range?
Thread Thread Starter Forum Replies Last Post
What's more important, ES or Group Size?? Jumpalot Rifles, Bullets, Barrels & Ballistics 15 05-03-2011 03:10 PM
group size ven Long Range Hunting & Shooting 4 02-11-2007 02:17 PM
Group Size and MOA Newbie The Basics, Starting Out 8 08-26-2004 06:05 AM
Group Size at 100 yards dakor Long Range Hunting & Shooting 4 03-25-2004 12:54 AM
group size travis20032003 Long Range Hunting & Shooting 2 10-24-2002 10:06 AM


All times are GMT -5. The time now is 09:27 PM.


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