Tuning seating depth for hunting loads

[ben-o]

I’m wondering about the best way to find the ideal seating depth for hunting loads. Loading Barnes bullets in a few different guns, I’ve found loads that will shoot in the 1/2 - 3/4 moa range, all with the bullets seated .050” from the lands. I’m ready to start playing with seating depth, but I’m not sure where to start. Is shooting groups in .010” or .020” increments likely to show me anything useful?

 

[TTE]

If a bolt gun, you need to take your magazine length into consideration.

If that is not a determining factor -

Find the 'jam' measurement then seat the bullets 0.020 shorter than the jam measurement, and see how they shoot.

Next reloading seat the bullet 0.23 from jam

Next reloading seat the bullet 0.26 from jam

Then compare group size to see if your groups are getting better or worse.

If better, keep seating them deeper until the groups get worse.

If the groups are worse, seat bullets closer to jam by the same 0.03.

Be careful not to get too close to the jam point/measurement, or you'll run into excessive pressure problems.

The above is my opinion

 

[Dusty Stevens]

Barnes bullets like to really jump. Id find a spot around .100 off the lands and set them where the neck ends up looking right at a driving band

 

[Cbashooter]

I’m wondering about the best way to find the ideal seating depth for hunting loads. Loading Barnes bullets in a few different guns, I’ve found loads that will shoot in the 1/2 - 3/4 moa range, all with the bullets seated .050” from the lands. I’m ready to start playing with seating depth, but I’m not sure where to start. Is shooting groups in .010” or .020” increments likely to show me anything useful?

Your accuracy is much more than adequate already for all big game hunting at ranges anyone has the right to shoot at.
No need to fine tune IMHO

 

[SRP Shooter 1]

Why waste ammo on something that already out shoots most hunting rifles.

KS

 

[ben-o]

Barnes bullets like to really jump. Id find a spot around .100 off the lands and set them where the neck ends up looking right at a driving band

That’s pretty much been my strategy up to this point. I think Barnes recommends starting at .050” and working out from there. I’m debating whether to just go straight to .100 and see if it gets better or worse, or try some smaller increment in between.

Dialing it in to within .003” seems excessive, especially considering component prices. But I enjoy shooting and trying to get everything as good as I can.

 

[ben-o]

Your accuracy is much more than adequate already for all big game hunting at ranges anyone has the right to shoot at.
No need to fine tune IMHO

I definitely agree that this accuracy is fine, but I still enjoy fine tuning things. All of this rifle shooting stuff is pretty dumb and irrational if we think about it too hard, lol

 

[Bill Norris]

As Dusty stated the Barnes bullet or at least all I've tried in 30 cal. have wanted lots of jump. A friend of mine just purchased a box of the 140 gr. match burners in 6.5 and he will probably be here at my place when loading and checking them out in his 260AI. So I will be able to see what that bullet likes as well.

 

[JackT]

Ben I too enjoy fine tuning the accuracy of my hunting rifles, I see it as a way to increase my chance of success in an accurate shot which becomes more of a factor at distance, I'll take all the help I can get. If chasing accuracy in a hunting rifle makes you smile keep going and let us know how it turns out.

 

[Murray Brook]

I use the 171 Barnes MB in my 7/08 and it likes .120 off the lands.

 

[Orr89rocz]

I usually try .010” or even .015” increments due to not wanting to waste components. After i find my powder node i may do something like .010, .020, .030, .040 etc or .015, .030, .045, .060. Which ever shoots best i try it again along with .005” increments up and down and narrow down from there

 

[Coyotefurharvester]

I started 0.050 off with Barnes in my 7saum shot well, shot some slow fire with wind call adjustment at 300 yards 0.055-0.06 off. Drop was spot on and all were in a nice round 1.5 inch ish in the post it sticky. Done.

 

[TTE]

I usually try .010” or even .015” increments due to not wanting to waste components. After i find my powder node i may do something like .010, .020, .030, .040 etc or .015, .030, .045, .060. Which ever shoots best i try it again along with .005” increments up and down and narrow down from there

From what I hear/understand/believe, bullets have a node the same as powder charges.
With a jump of 0.010, you may jump over a 'bullet node'.

However, you could be correct and I could be wrong. I'm no ballistics wiz .... as I can barely figure out that 2+2 = 5 ..... wait, .... 4, it;s 4 ............... (see what I mean)

 

[Orr89rocz]

From what I hear/understand/believe, bullets have a node the same as powder charges.
With a jump of 0.010, you may jump over a 'bullet node'.

However, you could be correct and I could be wrong. I'm no ballistics wiz .... as I can barely figure out that 2+2 = 5 ..... wait, .... 4, it;s 4 ............... (see what I mean)

Thats true, atleast in some instances. However its like Bergers recommendations in their jump test. One of those groups “should” stand out. Course adjustments. When you see something that’s noticeable then you can fine tune.

Its worked ok for me in several rifles. Sometimes you nail it immediately. Sometimes none of them seem to work, in that case maybe that bullet and powder just aint gonna work. But i hear ya. My last 300 wsm load i tried .020, .025, .030 off. 30 looked best. But wasnt ideal. I then tried 33, then 36. 33 was no. 36 was close . Tried 39 and 42 and both of them were single hole. Chances are if i had .030 and .040, id have found it. But if i had say .025 .035 .045 i may have missed it. Idk

 

[K22]

If it isn't broke, don't fix it. As others have so eloquently said, you don't need to mess with this for a hunting application. Spend your components on becoming a better field marksman and hunting.

Of course, if you enjoy experimenting as part of the hobby, then that's different.

Personally, I'd rather be hunting or engaging in practical range practice but that's just me.

 

[Cbashooter]

In light weight narrow stock hunting rifles evaluation of a load that's already shooting under .75 moa is often difficult. Too many other factors come into play other than tuning the load a wee bit.

It's just a hobby so its all fun and up to the guy who owns the rifle.

Story-
When I was in my 20s I was an 80 mile a week runner.i was a pretty decent 10k runner.i went to an elite running store about a custom running shoe. The owner laughed at me saying "if you were a sub 4 minute mile guy maybe you'd save a second, but your a 5:30+ mile guy..don't waste your money.
Same with guns..

 

[Orr89rocz]

I guess it depends on the hunting. If long range stuff then its worth pursuing half moa or so, whatever you can get there with high bc stuff. For most under 300 yards or so if its sub moa you should be good to go

I deer hunt with my 16 lb bull barrel long range rig in powerlines so im obsessed with single ragged holes at 100 yrds. Berger vld seating .003-.005 increments has been necessary. My other guns for 100 yrds wood hunts one inch groups are more than perfect lol i had 2.5” group slug guns i was happy with too

 

[CaptainMal]

As stated above, 1/2 to 3/4 MOA is pretty good for a hunting gun. If you want to do seating depth tuning - go have the fun. It will take lots of rounds at a rather large expense in components and barrel life. You may not really find anything except to cause more throat recession.

That alone could alter your results. Your money, time and components need to be weighed with the fun doing it. Just be sure you never jam a bullet used for hunting and it all fits in your magazine or however the shells are contained.

 

[ben-o]

Well, folks thanks for all the input. I went out this morning, and in tough wind conditions, shot 2 groups with my Cooper 280 at 200 yards. One was seated at .050 and another at .100”. I’m sure the wind was a bigger factor than the seating depth, but the .100” group was slightly better. I’ll probably try a few more if I can get to the range on a calmer day.

 

[Cbashooter]

As long as you're having fun don't listen to anybody. That's what it's all about anyway