Getting the Best Precision and Accuracy from Berger VLD bullets in Your Rifle

[Eric Stecker]

Originally Posted by Lyons7STW

I have noticed that the oal of my projectiles varies considerably. Is this normal with bergers or did I get a rough batch?

Lyons7STW,

It will be easier to address your situation with a bit more information. Which bullets do you have and what is the lot number? What OAL measurements are you finding in this lot? Have you shot these bullets to see how they perform?

It is normal for the bullet OAL to vary as much as .025. We work to minimize this result but OAL variation of this amount is not uncommon and within tolerances.

It is important to keep in mind that OAL is not as critical a dimension as others. For example, the variation on the distance from the base of the bullet to the end of the bearing surface (or where the bullet engages the rifling) will vary less than .003 and in many lots will vary only .001. Greater variation in this dimension can negatively impact performance.

The only way the bullet OAL variation will affect performance is if you also notice considerable differences in the OD of the meplat (tip). If the meplats are different diameters then the drag on these bullets will vary causing vertical dispersion.

NOTE: Some meplats will look as if they vary due to how the tip formed. It is important to mention that the critical dimension of the meplat is the distance from the outside edge to the other outside edge. Even if the inside of the hole looks different it won't matter if the diameter of the outside edge is the same.

The way we overcome this result even though we can't eliminate the bullet OAL variation of up to .025 is to slightly over point the bullets. This gets a bit complicated but I'll try to make this clear with an example.

If a bullet with an OAL of say 1.150 has an outside meplat diameter of .062 and another bullet with an OAL of say 1.125 has an outside meplat diameter of .080 then there is a problem.

However if the bullet that is 1.150 long is slightly over pointed then the excessive material is forward of the meplat but has no influence on the size of the meplat (it doesn't make it smaller or bigger) so it will not affect drag. This means that the drag or BC of this bullet is precisely the same as the drag of the bullet that has an OAL of 1.125 since the meplat's outside diameters are the same.

NOTE: Over pointing occurs when the bullet tip reaches the end of the ogive portion of the die. Some refer to the appearance of an over point as a "flare". At this point the material no longer makes a smaller meplat but rather makes a meplat of the same size by the material moving forward rather than inward. A meplat can only be as small as the hole in the die that allows the ejection pin to pass through the die to eject the bullet. So as long as the shortest bullet reaches this point on the die the bullets will perform just fine.

Eliminating OAL variation is extremely difficult and in many lots impossible. We set up each run to over point the longer bullets deliberately so that we significantly minimize or eliminate the affects of OAL variation on performance.

Regards,
Eric

[Lyons7STW]

The part # is 28501. Lot# 2831.
It was a while before I caught on but what I have left varies between 1.415 and 1.438
I have shot up most of the box in load development. So I can not rule out other factors as the cause of my frustration. What tool do you suggest for measuring oal.

I had a great group going and had to switch presses. I thought I got everything reset but the next batch using the same components shot like crap.

[Eric Stecker]

Lyons7STW,

I am confident that the OAL of the bullet is not causing the poor performance. I could go into a long list of specific reasons why I believe this but that will take a while and the end result will be the same. This difference is .023 and is not uncommon especially in the long VLDs like the 7mm 168 gr VLD.

Have you tried the 4 COAL test with these bullets?

Regards,
Eric

[Lyons7STW]

I have the new batch worked up as you descrbed in you article. I have already gone from 3.685 which is jammed pretty well back to 3.665 in 5 thou increments. I did not stumble on this article till I was having issues and started looking for answers. The "old way" of smoking the bullet and letting the lans just knock the soot off, had always worked with the ballistic tips I used in all my other guns. I actually had this gun built to use your bullets since everyone told me you couldn't let them free bore and unless I had the barrel cut to fit them they wouldn't fit the mag.

I guess I jumped the gun thinking I was in the sweet spot already when I got that good 8 shot group and was baffled I could not repeat it. I have never taken this long in load development before. I still believe it will be worth it!

Oh and thanks for your patience, yall are the best customer service I have ever dealt with anywhere!!

[NotsubMOA]

The first time I ran across the VLD Hunting bullet description on midway, I was positive that if it's advertised terminal performance was accurate, no matter what, I was going to use it. Taking any companies performance claims as "The Gospel" without any evidence to support them isn't usually my style, but I just had a feeling about this one.

Using the Hornady OAL Gauge I checked ten bullets out of the box to get my seating depth. Nine times I got a 2.7295" OAL with a lone 2.730". I loaded 20 cartridges and ended up with 18 at 2.7295", 1 at 2.730", and 1 at 2.729" OAL. That's pretty dang consistent for me.

I've only been handloading for a few years and just ordered my first set of "competition" dies this week so this is with regular RCBS dies...this is my first dealing with Berger bullets. Needless to say I'm impressed. Keep up the good work and thanks for the in depth info about finding the sweet spot because I've been fighting my 25-06 to find a bullet it likes. With this info and a box of VLD's I feel confident I'll get an acceptable load worked up before the weekends over.

[Lyons7STW]

Thanks, Eric
I wanted you to know I got my issues resolved with your advice. The rifle shoots well under MOA at 300 yards in these Texas winds. I haven't shot for group past that but was slaying milk jugs at 600 in a 16 mph gusting cross wind. These things buck the wind like crazy!
Last week I shot a nice antelope and three big coyotes with the 7 mm 168grn Hunting VLDs @ 3050 fps mv.
I was very pleased. There was no tracking necessary! I have posted pics in other threads.
CUSTOMER FOR LIFE!

[Eric Stecker]

Originally Posted by Lyons7STW

The rifle shoots well under MOA at 300 yards in these Texas winds.

I'm glad to hear that your situation is squared away. I know what you mean about those Texas winds. On the Oct. 8th weekend I went on a management hunt at the Diamond K Ranch outside Brady, Texas.

I dropped a management buck with one shot at 1,017 yards which is my longest shot on game. We spent a lot of time on Donald's (ranch owner) range which goes out to 1,000 yards. The circumstances allowed us to wait on the wind to let up.

We were filming for two episodes of the Extreme Outer Limits TV show. I had the added pleasure of hunting with Dave Arnberger from McMillan Rifles and Kyle Brown from Night Force. Both are great guys and both got kills at 1,000+ yards. It was a blast.

Regards,
Eric