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Question on COAL?

tomcatfan

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Minuteman
Nov 22, 2010
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Southern MD.
Being new to reloading I am trying to read as much as I can. So I read the post titled "Hand Loading For Long Range 3; Finding Start OAL" here on the forum. This opened up so many questions.

So in doing something very similar I found the bullet starts engaging my rifling with a COAL of 2.863" in a Savage 10fp 5r. Every reloading documentation I have states that the .308 win should have a max OAL of 2.80. Are the reloading manuals being conservative or should I load to the 2.863"?

Second, is there so much wrong with bullet jump? In reading some peoples discussions, their rifles prefer bullet jump.

I have only reloaded a couple of rounds, but haven't been able to shoot them yet. I based my reloads as much as possible off of the most accurate rounds I have found. I was able to get .3 MOA with a 3 round shot group using Fiocchi 175gr match. They use the SMK 175 grain round with a measured COAL of 2.778".

So to say the least I am a little confused on what I should do. Should I make my COALs longer?
 
Re: Question on COAL?

If you load each round 1 at a time, then they can be any length you like, other wise they will need to fit inside your mag.
They can be no longer than your magazine.
My Remy likes 5 to 10thds. off the lands.
I have the best luck with measuring the lands 5 or 6 times and taking an average.

By the way, different bullets have different lengths which will change from bullet to bullet.
I like to measure from the ogive of each different bullet.
 
Re: Question on COAL?

There is a significant difference between the max length and the best length. Most rifles shoot their best with a bullet jump of 25 thou to as much as five or six times that much.
 
Re: Question on COAL?

Ignore the max OAL.

In almost all cases a bullet will shoot better when touching the lands, or a fraction of a fraction in front off the lands. Bullets can still shoot well with jump but it will almost always shoot better than "well" without the jump.

However if you are consistently getting fantastic results with jump, then there may not be a reason to try any differently.

Thats how I see it anyway.
 
Re: Question on COAL?

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">By the way, different bullets have different lengths which will change from bullet to bullet.
I like to measure from the ogive of each different bullet.</div></div>

Savage 10fp, Be careful about this. He is correct, all bullets are not the same from the ogive to the meplat (tip). Get an OAL gauge and a comparator so you know exactly where the ogive is in relation to the lands. Then make your adjustments. Also be careful about seating the bullet tight to the lands or jambing. Either can cause pressure to become very high in a hurry.

By the way, <div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">.3 MOA with a 3 round shot group</div></div> Sweet!!!
 
Re: Question on COAL?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: m. Dalton</div><div class="ubbcode-body">If you have not read. read the ABCs of reloading. This book will save you a lot of headaches.. </div></div>

I have that book and your right it has been extremely helpful. But with that being said as people have developed thier "sweet spot" loads using the black magic and vodoo that they use, I don't think you can teach that in a book.

With out having an experienced roloader that I can talk to, I figured I would join something like this forum and try to leaverage the expertise of you guys. Thanks.
 
Re: Question on COAL?

The best thing you will pick up from forums like this is technique and knowledge which will allow YOU to make decissions that will get YOU the best results for YOUR gun. No two guns are ever the same and even though some like similar items loaded a similar way NEVER think any two will like the exact same load.

Forums like this and others will greatly excellerate your learning curve because there are lots of people all giving input. Ask a question then read thru the responses and when you start getting the same answer from multiple sources that is usually a good indicator it's the right answer. The better you educate yourself the easier it will be for YOU to come up with the right answer that works best for YOU. Don't be so concerned about getting just the answer part. Be more concerned about HOW they came up with the answer.
 
Re: Question on COAL?

The posts above about different bullets having requiring different COAL'S is very true. In my 10fp the 155 scenar touches the lands at 2.852 and the 210 SMK touches the lands at 2.928. I haven't got to the range with the 210's yet but the the 155's are dead balls accurate at 2.845 coal.
 
Re: Question on COAL?

My current 308 load is with 155 scenars loaded to 2.8" coal to fit into my mags. This = almost .060" jump in my rifle. Accuracy is exceptional.