Long Range Hunting Online Magazine


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


Reply

Why doesn't accuracy always hold up?

 
LinkBack Thread Tools Display Modes
  #8  
Old 10-28-2003, 05:06 AM
Bronze Member
 
Join Date: May 2001
Location: Houston, Texas
Posts: 95
Re: Why doesn\'t accuracy always hold up?

D.C.,
Thank you for the feedback. Mind you, what you've said makes me think that the .408 CT might really do all those few who developed it say it will do at great distance, despite the fact that I've never seen anything in the way of respectable accuracy out of the things at distances as far as 600 yards save for a few fluke groups that measured sub-0.25 MOA.

Brent,
Damn, you've got a mind like a steel trap, amigo! I can't believe you remembered that I mentioned that my .300 WSM's tube has a 1:12 twist. By the way, I'm sorry I didn't get back to ya personally about the accuracy of this Lapua 185-grain load. Now you know!
Incidentally, I've gotta e-mail you some pics of some of the extraordinary 20-round groups I've managed from a prone position (using a Harris bipod and Accu-Shot monopod) with this rifle and the subject Lapua 167-grain load. You'll be incredulous. The smith (Pete Pieper @ Precision Barrel Work) who did the rifle even wants to put up pics of it along with one of these targets at his website! Imagine that!

Regards,
Dave

[ 10-28-2003: Message edited by: Houston Boy ]
__________________
If you can see it, then you can hit it!
Reply With Quote
  #9  
Old 10-28-2003, 09:28 AM
Platinum Member
 
Join Date: Jun 2007
Location: Fredericksburg VA
Posts: 4,120
Re: Why doesn\'t accuracy always hold up?

From the obvious reasons everyone has listed here are some more for anyone shooting long range. Basically bullet uniformity is the key to exceptional LR grouping.

1. Variations in the length of the bullets bearing surface within a given lot of bullets. This will effect the bc and often give vertical. I have seen variations as much as .020 in one box of 100 sierra bullets.

2. Variance in the bullet metplats. Same as above.

3. Variance in bullet weights in a given box or lot.

There have been several very good LR smiths and shooters that long discovered and been preaching that the best way to accuracy is the "best quality and most uniform" bullets.

Right now there is a move to Flat base LR match bullets in fast slow twist barrels. BIB has a great 187 that is shooting fantastic in 1-12 and up to 1-14 twist 30 cal barrels at 1000. Several 6.5 flat base bullets are coming out this year for 1-9 twists.

BH
Reply With Quote
  #10  
Old 10-28-2003, 01:32 PM
Writers Guild
 
Join Date: Jul 2001
Posts: 1,459
Re: Why doesn\'t accuracy always hold up?

Houston Boy, since you are using a good quality bullet, I will leave bullet manf out of the discussion.

What I would suggest is that the 1 in 12 twist of your barrel/muzz vel, is not spinning the bullet fast enough and the bullet is loosing stability at LR. Either increase muzzle vel or go to a faster twist and problem will correct itself. Remember that twist rate will vary even with the same numerical twist. Also, internal dimensions of the rifling will affect the true spin rate of the bullet.

Are you using the same powder? Maybe the burn rate is not suited to the heavier bullet? A change in powder may help with vel variations and thus stringing. How are the vel spreads?

Otherwise, the LR performance should be similar to groupings at ranges beyond 200yds (I like to test at 250yds) as long as wind is not a factor and the bullet stays supersonic.

Jerry
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: Why doesn't accuracy always hold up?
Thread Thread Starter Forum Replies Last Post
hold zero Johnny Boy Long Range Scopes and Other Optics 3 08-25-2008 09:54 PM
to hold or not trb0 The Basics, Starting Out 3 01-07-2006 12:28 PM
Mil-Dot Hold Over Question dakor Long Range Scopes and Other Optics 26 10-15-2004 06:58 PM
Using mildots for hold over Willy 1 Long Range Scopes and Other Optics 1 09-13-2002 11:31 PM

Current Poll
How Many Different Cartridges Do You Reload For?
ZERO, all factory ammo - 8.05%
359 Votes
1 - 2.78%
124 Votes
2 or 3 - 14.62%
652 Votes
4 or 5 - 20.38%
909 Votes
6 or 7 - 14.82%
661 Votes
8 or 9 - 8.63%
385 Votes
10 or more - 30.72%
1,370 Vote
Total Votes: 4,460
You may not vote on this poll.

All times are GMT -5. The time now is 02:40 AM.


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