Seating Depth Increments?

[USAF Ret]

What increments do y'all use when seating depth testing. I have heard folks doing as little as .003 and Barnes says .015. Would love to hear thoughts.

 

[Caseknife]

I usually us increments in the .010-.020". Seems to me anything less is a waste of components and time.

 

[Sheltowee]

I usually us increments in the .010-.020". Seems to me anything less is a waste of components and time.

^this. I will usually do .025" increments with Barnes bullets.

 

[N2TRKYS]

I find that adjusting seating depths to be a waste of time.

 

[VikingsGuy]

When I’ve done it I have done it in 0.015 increments - but found it more trouble than it was worth. Difference where too close give the statistics of 5 shot groups. Not needed for hunting accuracy- and a moving target for range volume given throat erosion.

 

[std7mag]

Over the years, I've learned what some bullets prefer on my hunting rifles.

Cup & core usually end up liking a 0.020" jump.
This works for almost all of the Hornady , and Sierra bullets. Nosler Ballistic Tips and ABLR.
But with everything, there are a few exceptions.

Nosler RDF seem to like a little longer jump. 0.030".

Berger VLD seem to like a much smaller jump. 0.005".

Monos like the jump. Cutting Edge MTH at 0.050".

What will really blow your mind is how much difference it makes when you tune your action!!!

 

[Addicting]

I find that adjusting seating depths to be a waste of time.

It depends on your reloading method.

If you do velocity node you need to tune with seating depth.

I’ve done 5 different seating depths on Barnes bullets starting at .030 off the lands at .020 increments. You can clearly see on the individual target groups tightening and opening back up as the depth changes. Sometimes it’s the first group I shoot that is the best, which would support your thoughts.

But each rifle / bullet combo has its own sweet spot, and you won’t see it if you don’t test the different depths.

 

[N2TRKYS]

It depends on your reloading method.

If you do velocity node you need to tune with seating depth.

I’ve done 5 different seating depths on Barnes bullets starting at .030 off the lands at .020 increments. You can clearly see on the individual target groups tightening and opening back up as the depth changes. Sometimes it’s the first group I shoot that is the best, which would support your thoughts.

But each rifle / bullet combo has its own sweet spot, and you won’t see it if you don’t test the different depths.

I’ve been lucky with the dozen or so rifles that I load for with the COAL listed on the load data. I haven’t had any trouble getting the bullets I want to shoot in any rifle at the velocity that I want to at least MOA type accuracy.

 

[Wind Gypsy]

I don’t bother with it much anymore either. Set bullets roughly 0.050” off and go. The really small increments are particularly worthless in rifles that erode throats at any considerable rate.

For a hunting rifle that most guys are going to shoot 3 round groups varying from say 0.5” to 1.25” or larger with the same load, small sample size seating depth test likely don’t tell you much. Maybe if it’s a temperamental load and one depth is shooting 2”+ but I haven’t seen that from just seating depth anytime I can recall recently.

 

[Addicting]

I’ve been lucky with the dozen or so rifles that I load for with the COAL listed on the load data. I haven’t had any trouble getting the bullets I want to shoot in any rifle at the velocity that I want to at least MOA type accuracy.

I guess it comes down to I’m not happy with just MOA and be done.

All of my rifles were built by a gunsmith. 15 rounds of ammo to get to the sweet spot is insignificant from a cost perspective. My OCD would never let me be happy if it was a 1/2 MOA gun being fed 1 MOA ammo.

 

[N2TRKYS]

I guess it comes down to I’m not happy with just MOA and be done.

All of my rifles were built by a gunsmith. 15 rounds of ammo to get to the sweet spot is insignificant from a cost perspective. My OCD would never let me be happy if it was a 1/2 MOA gun being fed 1 MOA ammo.

All of mine are factory rifles and are usually 1/2” groups. I find that if it takes a seating depth adjustment to get accuracy, then it’s too finicky of a load.

Some folks like to tinker with stuff, though.

Heck, I don’t even know or care how far off the lands I am.

 

[USAF Ret]

.050 jump. Best group so far. I have one more load set at .060, but did not have time to test.




Full test set

 

[std7mag]

Have you tried 0.020" off the lands?

Starting at 0.050" off the lands is usually used for monolithic bullets.

 

[USAF Ret]

Have you tried 0.020" off the lands?

Starting at 0.050" off the lands is usually used for monolithic bullets.

Yes, I was .020 off lands with the recommended COAL. It shot a .94 MOA.

 

[std7mag]

I'm curious about the 2 fliers at 3.276".

Might want to reshoot it again.

You didn't say your method of shooting.
Leadsled?
Bipod & shoulder?
Bipod & rear bag?
Front & rear bag?
Front rest & rear bag?

 

[USAF Ret]

I'm curious about the 2 fliers at 3.276".

Might want to reshoot it again.

You didn't say your method of shooting.
Leadsled?
Bipod & shoulder?
Bipod & rear bag?
Front & rear bag?
Front rest & rear bag?

Yeah, those threw me way off. They were the last 2 shots. Agree, may need to shoot again.

Front rest, a Caldwell, rear bag. Very steady.

 

[Addicting]

Group 1 and 2 was you somehow with flyers. I would shoot both as 3 shot groups with plenty of cooling in between shots.

 

[Wind Gypsy]

Chasing unicorns.

 

[Waspocrew]

I like .020" off initially. Increments of .020" after that.

 

[USAF Ret]

Group 1 and 2 was you somehow with flyers. I would shoot both as 3 shot groups with plenty of cooling in between shots.

I was letting it cool after every 2-3 shots by feeling the barrel. Waiting about 5-10 min until it was barely warm. I am going to finish this last group out and maybe test the .070 depth and see what those results are before I go back. Group 3 is perfectly acceptable for hunting, so anything else is just more data.