Max COAL questions

[WildRose]

Unless you're shooting VLD's I haven't found it to make a whole lot of difference. Years ago I started following the advice of a fellow poster here who stated it wasn't worth worrying about so he loaded everything to mag length and then adjusted powder charges for best accuracy in his rifles.

I bought one of his custom rifles when he needed to cut down the collection due to a move and followed that advice and it was spot on. I then started trying it with my other rifles and found it producing far, far better results than trying to stick to SAAMI standards.

With VLD's you really need to set them close to or into the lands because of their shape which does not allow for consistent or accurate self alignment with the bore.

There's a good article here in Accurate shooter that explains it pretty well.

Tangent, Secant, Hybrid Ogive Bullets within AccurateShooter.com

 

[243winxb]

Getting The Best Precision And Accuracy From VLD Bullets In Your Rifle

Berger bullets. Getting the Best Precision and Accuracy from VLD Bullets in Your Rifle | Berger Bullets Blog

Load 24 rounds at the following COAL if you are a target competition shooter who does not worry about jamming a bullet:
1. .010 into (touching) the lands (jam) 6 rounds
2. .040 off the lands (jump) 6 rounds
3. .080 off the lands (jump) 6 rounds
4. .120 off the lands (jump) 6 rounds
Load 24 rounds at the following COAL if you are a hunter (pulling a bullet out of the case with your rifling while in the field can be a hunt ending event which must be avoided) or a competition shooter who worries about pulling a bullet during a match:
1. .010 off the lands (jump) 6 rounds
2. .050 off the lands (jump) 6 rounds
3. .090 off the lands (jump) 6 rounds
4. .130 off the lands (jump) 6 rounds

I shoot VLD's in a Rem 40X 243win. More importand that the bullets shank is in full contact with the case neck. a COL thats to long, causes it own problems.

I dont agree with the Berger method, to much adjustment. The full diameter of the bullet shank should be in contact with the case neck. If COL is to long for the magazine or bullet is into the rifling, make the COL shorter so the round fits. Use the starting powder charge and work up for accuracy. Take the best load, now vari the COL by .010" to fine tune. This works for all bullets, not just VLD ones.

 

[xxtavixx]

Re: Getting The Best Precision And Accuracy From VLD Bullets In Your Rifle

Thanks for all the input. I picked up the hornady comparorator and what a dofference. I tested my 20 rounds and almost all where 2.802, my furthest off was a 2.790. That was one of two not within .005.

Measuring the lands of my savage was a little tricky at first, but i almost always got 2.864, 2.866 or 2.863. The ejector is a little happy so its hard to stip the round from hittimg the chamber when being removed with a bullet. Magazine length is not a problem for this, luckily!

For fun i measured a few core lokt rounds ogive to see their variance in cbto...it took 3 for me to get one that was more than .05 off!

 

[FEENIX]

The 3.340" is just a SAAMI maximum standard. Nothing more.

I don't think anyone is disputing that!

The 3.320" COL is their tested COL. 3.340" is the max COL.

That makes sense. This is the first manual that I've seen that actually shows their tested COAL; I double checked all my manuals and all just noted the SAAMI COAL ... interesting, nonetheless.

 

[xxtavixx]

So the more I read, the more people suggest starting at .020 off the lands and trying different powders all at .02. From there they take the best shooting powder and then adjust the bullet seating depth. I have heard many people suggest that anything furher than .05 from the lands is wasteful and create excessive pressure.

Is there enough truth in this where pulling the bullets would make sense? My loads are at 2.802 and they would touch the lands at 28.64, so I have a "gap" of .062 - it seems like bumping them .042 closer would be the normal starting point.

Thank you for all the input again!

 

[John99]

Bullet overall length has never been consistent. Once you realize this the better off you are. You need to stay with CBTO or Case Base to Ogive measurement, its more consistent and you will get more consistent reloads. I have played the 'lands' game before. And flirting with disaster is in the mix. Too close to lands and pressure spikes can do bad things. I would advise think about honing your external ballistics skills rather than playing with seating. Just find a nice spot 20-30 off lands and just try different powders. That would be a more efficient use of your time, of course imho. I go with the old saying, beware of a man with one gun theory.. best of luck

 

[rcoody]

Re: Getting The Best Precision And Accuracy From VLD Bullets In Your Rifle

Berger bullets. Getting the Best Precision and Accuracy from VLD Bullets in Your Rifle | Berger Bullets Blog


I shoot VLD's in a Rem 40X 243win. More importand that the bullets shank is in full contact with the case neck. a COL thats to long, causes it own problems.

I dont agree with the Berger method, to much adjustment. The full diameter of the bullet shank should be in contact with the case neck. If COL is to long for the magazine or bullet is into the rifling, make the COL shorter so the round fits. Use the starting powder charge and work up for accuracy. Take the best load, now vari the COL by .010" to fine tune. This works for all bullets, not just VLD ones.

The berger method has worked for.me. looking for.a.mag length load for the VLD hunting bullet was quite frustrating until i used the Berger jump test. Found my jump . 127 off the lands. Who would of thought. Here is the fine tune. Each group is .010 less. You can see the node.is .03 wide

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