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Buster Hemlock

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Feb 26, 2019
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217
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It really depends what the intended use of the rifle is when determining what is acceptable for ES and SD. Lower is definitely better but chasing single digit SD and teens for ES isn't necessary if it's a 300 yard deer rifle. If it's a 800+ deer rifle or competition rifle, different story. Plug into a ballistic app the high and low velocities, your ES and see how much the elevation differs at the range you intend to use your rifle and decide for yourself. I have a .243 win and it would drop 10 shots in 3/4" inch at 100 yards with a ES of 150+ FPS, take it out to 300+ and it was a pattern not a group. Needless to say I did some work to get stuff tightened up for my intended use
 

MagnumManiac

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Feb 25, 2008
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2,269
I am more interested in a low Extreme Spread (ES) than a single digit SD.
The reason is due to impacts at longer ranges, if velocity is swinging that much, it makes hits at those ranges more difficult.
Also, ALWAYS go by what the target is telling you, there’s no point getting low ES/SD numbers and the bullets are spraying all over the target. Getting low numbers does not make the load a shooter.
I have a load in a particular rifle that at 100 is pretty much BR groups, 10 shots in the same hole...yet the ES is 100fps. The bullets just exit in the oscillation at a point where it is still at either end of the velocity range, it’s a fluke that is rare to be sure.
Your example above of a ES of 30 is about as good as an untuned load gets in a standard rifle. Tweaking seating depth and/or charge may bring it down to the teens, but only change one or the other.

Cheers.
 
Last edited:

Tom Erickson

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Nov 16, 2019
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92
Location
Minnesota
I am more interested in a low Extreme Spread (ES) than a single digit SD.
The reason is due to impacts at longer ranges, if velocity is swinging that much, it makes hits at those ranges more difficult.
Also, ALWAYS go by what the target is telling you, there’s no point getting low ES/SD numbers and the bullets are spraying all over the target. Getting low numbers does make the load a shooter.
I have a load in a particular rifle that at 100 is pretty much BR groups, 10 shots in the same the same hole...yet the ES is 100fps. The bullets just exit in the oscillation at a point where it is still at either end of the velocity range, it’s a fluke that is rare to be sure.
Your example above of a ES of 30 is about as good as an untuned load gets in a standard rifle. Tweaking seating depth and/or charge may bring it down to the teens, but only change one or the other.
So your looking for e s under 20 .I'm new to reloading would you play with seating depth or charge to start with .I'm 125 fps then what the book said I should be and I'm .1. Grains under the max where would you start?
 

MagnumManiac

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Joined
Feb 25, 2008
Messages
2,269
I start with seating depth.
I load the middle load of the powder I want to try, 3 rounds @ .010”, 3 @ .020”, 3 @ .040”.
If this shows no promise, I then do the Litz seating depth test, but most of the time .020-.030” has worked for me, except with Nosler RDF bullets, they like kissing the rifling in my Comp gun. I would not load like this for hunting, however.

Read as much as you can for seating depth.
There is no magic number unfortunately.

Cheers.
 

Tom Erickson

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Nov 16, 2019
Messages
92
Location
Minnesota
how many rounds do you shoot i was shooting 10 if I change the bullet depth do I need to shoot 10 or can I get by with 5
 

7070yshot

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May 26, 2020
Messages
43
Location
Liberty Hill, TX
All great responses! The biggest question is really the intended purpose. A hunting rifle you never intend to shoot past 100,200,300,400,500 ? And I’ll go out on a limb and say 500y is probably max for something with SD’s in the 15-30fps range for an ethical kill. If you can shoot a 1in group at 100 that’s a 5in group at 500y. About the size of most DRT kill shots.
I’ve watched hundreds of handloading/hunters. 600-700y is where the wheels come off their ammo. If you want to target shoot SD’s of 10 and below are what you need. Thats going to take you past 700y.
bullet selection becomes extremely important at this level as well but that’s another post.
Good luck sir!
 

Bang4theBuck

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Joined
Nov 19, 2013
Messages
421
Lots of good responses, but wanted to reiterate as was said above that the best way to learn what you are looking for is to plug the fastest velocity and the slowest velocity into a ballistic calculator, individually, and determine what the difference in real drop is at your longest expected shot distance. Honestly, I then add a little 'me factor' to that delta, and decide if I need to improve the ESs. If any of this is confusing, or if you need help with inputting into a ballistic calculator, Feel free to PM me, and I will help/explain.
 

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