Berger Seating Depth Test

[TK 1985]

Alright so the following comes right off Berger's site as well as a nice sticky on this forum:

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

How many of you use these distances? .040 at a time seems like a lot. I have been finding my max with the Hornady OAL gauge, and the first load is .005 off the lands, then take it back in .005 increments. Am I doing too fine of adjustments because it does not seem like most bullets like a huge jump?

 

[Buckammo]

I followed the .040 increment with my last load development with the .277" Berger 150 VLD. The best seat depth was at 0.090" off the rifling. The accuracy was good enough that I did not try to fine tune the seating depth any further. It is a 3/4 MOA hunting rifle.
John

 

[cowboy]

Alright so the following comes right off Berger's site as well as a nice sticky on this forum:

How many of you use these distances? .040 at a time seems like a lot. I have been finding my max with the Hornady OAL gauge, and the first load is .005 off the lands, then take it back in .005 increments. Am I doing too fine of adjustments because it does not seem like most bullets like a huge jump?

To answer your question - I have used these distances with the typical Berger VLD hunting bullet a lot of times on working up loads in various rifles for other people as well as my own rifles. It works and don't be surprised if you find being .090 or .130 off is where you find your best results. Has happened many times. You didn't mention what caliber or weight of bullet but if it were me and Berger had your weight of bullet in their "classic" line - I'd go that route and give up a little BC. The classics are not touchy on COAL.

Also keep in mind that there is a lot of pressure/velocity difference between being .010 off the lands versus .130" off if you use the same amount of powder. You do not want to be on the high end of the pressure chart at .010 off and then start shoving that bullet deeper into the combustion chamber.

 

[benchracer]

To answer your question - I have used these distances with the typical Berger VLD hunting bullet a lot of times on working up loads in various rifles for other people as well as my own rifles. It works and don't be surprised if you find being .090 or .130 off is where you find your best results. Has happened many times. You didn't mention what caliber or weight of bullet but if it were me and Berger had your weight of bullet in their "classic" line - I'd go that route and give up a little BC. The classics are not touchy on COAL.

Also keep in mind that there is a lot of pressure/velocity difference between being .010 off the lands versus .130" off if you use the same amount of powder. You do not want to be on the high end of the pressure chart at .010 off and then start shoving that bullet deeper into the combustion chamber.

Well said!

 

[Mike 338]

I use .040" increments just as stated. Since I intend to use the magazine, I start at maximum mag length, assuming it doesn't touch or jam the bullet into the lands, and begin from there. I find a safe powder load, usually around 2% below max and seat strings of bullets in said increments as deep as I can get them without going off the ogive. I've had noticeably more accurate groups at .220" off the lands which is almost 1/4". They shot fairly consistently in and around that band of seating depth. Point being, you don't know till you try it. After finding max powder charge, this is one of the very first things I do in load development because if you aren't in the best accuracy band, often nothing will shoot very well. I do this with all bullets, not just Bergers.

Note: Change the bullet and you gotta start the test over.

 

[revjo1]

I just got a new 5x20 night force shv scope and I'm putting it on my browning a bolt 300 win mag an I'm kinda new to reloading,but I've heard a lot of good stuff about burgers for hunting so I got some 190 vdl and going to give them a try. I have some Mir 4350 that I used to load with my 180 nosler partitions but I'm green as grass with the Bergers so any I put will help.

 

[TK 1985]

I usually use hornady bullets but this wasn't for any particular load.it seems like the consensus is to use the bigger increments then fine tune.

 

[jrock]

I don't want a jam so I picked the hunting method and used all of the depths. Yes, use what they recommend for the first test and then when you find the best depth, doe another test narrowing it down with 0.010 or 0.015 increments. I find the sweet spot is about 0.015 wide.

 

[Mike 338]

I usually use hornady bullets but this wasn't for any particular load.it seems like the consensus is to use the bigger increments then fine tune.

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