Great video on seating depth testing

[hawlejr]

I've watched it twice. The guy is talking so fast, I never did get what the seating depth changes were. Anybody know what the differences were between #1, #2, and #3?

 

[cjuve]

I have an F-Class rifle and it shoots everything small at 100 but everything does not shoot small at 600 yds.

My hunting rifles don't shoot everything small at 100 and just because something at 100 shoots small still does not mean that it shoots small at 600.

I don't actually think the video has a lot to do with seating depth testing but more to do with how you can be fooled by small 100 yd groups.

 

[Beluebow]

As a percentage of charge weight, what increment change do you consider significant?

I think it is dependent on any on given barrel and where you are in a particular charge range. I know that sounds like a chump answer but it...."depends".

 

[FireFlyFishing]

So I'm probably slightly biased in my view point. All of my guns, especially as of late since @Barehandlineman11 has been building them, have shot extremely well. With a variety of bullets and powders. So much so, where I literally cannot consistently shoot a positive difference in small seating depth changes or charge weights. The last 4 barrels have shot sub .5 MOA 5 shot groups with the first charge weight and seating depth of several bullets and powders.

I think this is the key to the video you posted and what you're saying here. "Custom" rifles with nice cut barrels using next gen cartridges should take much less tweaking than factory rifles chambered in a legacy cartridge. If they're not easier, why spend that much $$$?

 

[Phil Rizzo]

I think it is dependent on any on given barrel and where you are in a particular charge range. I know that sounds like a chump answer but it...."depends".

Understood. Some say there is a minimum to be significant.
I'll try .1 changes every time. I mean hell we go through all these other steps to be the best.

 

[Barehandlineman11]

Seating depth is a course adjustment and powder is fine adjustment. Same way barrel tuner works

 

[Phil Rizzo]

Those .003" increments might not shrink the size when you are close, but they sure change the shape.

 

[Beluebow]

One opportunity that shooting Fclass provides that hunting or even benchrest doesn't provide, is long continuous strings of fire. Having access to a much larger sample size of how certain changes fail or succeed negates a lot of the "sample size" arguments. Typically most shot strings are 17-30 per relay. That's a decent sample size by anyone's standards I would think. And some of us don't shoot mouse fart guns.

That said it doesn't discount personal experience.....if you think it matters it probably matters...right or wrong. More than one way to skin a cat as they say.

 

[nealm66]

I have an F-Class rifle and it shoots everything small at 100 but everything does not shoot small at 600 yds.

My hunting rifles don't shoot everything small at 100 and just because something at 100 shoots small still does not mean that it shoots small at 600.

I don't actually think the video has a lot to do with seating depth testing but more to do with how you can be fooled by small 100 yd groups.

I've definitely seen really good 100 yard groups fall apart at distance but man, you have to be careful saying that. So many strong opinions

 

[ChrisInKY]

Here's a real world example from a few days ago. This was my REM 700 Sendero SF 2 factory rifle shooting 220 grn SMKs. The upper left target was a pressure ladder for a different rifle. I changed the seating depth 0.006" for each group. As you can see, there are differences and the barrel like different seating depths over others. The SMK is a very forgiving bullet too. I used three shots per group to save on ammo. If it can't shoot 3 shots well, it won't shoot 20 well either. The smallest group pictured was 0.256". The next smallest was 0.40". I'm not saying the gent in the vid is wrong by any means. I'm just showing what has worked for me in my rifles doing load development.

Here's another video of the same guy ... saying the same thing ... you and I both have seen from our own hand-loading efforts.

 

[Kivaari]

Yep, don't chase lands. Chase the node.

 

[Barehandlineman11]

I've definitely seen really good 100 yard groups fall apart at distance but man, you have to be careful saying that. So many strong opinions

Its where the discussion of es sd dont matter to some and do too others. It doesnt for guys shooting close range it does in real long range. Es sd on a chrono doesn't matter its just a tool to help speed things up. Es sd on target matters though which is why you see good groups at 100 fall apart at 600+ it actually falls apart leaving the barrel you just see more dispersion further you go. Which is your extreme spread. Anyone denying es doesn't matter failed 7th grade science. A projectile of same size and weight wont impact the same spot at different speeds physically impossible.

 

[Beluebow]

Es sd on target matters though which is why you see good groups at 100 fall apart at 600+ it actually falls apart leaving the barrel you just see more dispersion further you go.

Most of the crowd will probably miss this part "on the target"....We see this all the time on electronic targets like the ShotMarker. Low SD's in the 4-6 range for a 20+ shot string in mild wind conditions, usually equates to a good rifle and load combo THROUGH THE TARGET. There are more factors involved to tuning a long range rifle to consistently agg small than just ES.

A projectile of same size and weight wont impact the same spot at different speeds physically impossible.

What are your thoughts on positive compensation?

 

[nealm66]

Its where the discussion of es sd dont matter to some and do too others. It doesnt for guys shooting close range it does in real long range. Es sd on a chrono doesn't matter its just a tool to help speed things up. Es sd on target matters though which is why you see good groups at 100 fall apart at 600+ it actually falls apart leaving the barrel you just see more dispersion further you go. Which is your extreme spread. Anyone denying es doesn't matter failed 7th grade science. A projectile of same size and weight wont impact the same spot at different speeds physically impossible.

I'm not sure it's as simple as that in my humble opinion but I honestly don't know the why. I only know we should shoot the 100yard group at distance to confirm just to be safe