I've decided to play with some loads to improve my long range shooting, 600 yds +, in two of my current hunting rifles. I chose them because they are the most accurate I have out to my normal hunting distances.(-1MOA) I have reloaded for about 40 years and played with a wild cat or two. I have never seriously shot beyond 500 yds. I may never shoot at anything but rocks and other inanimate targets beyond that range but want to see how well I can do. So getting to my question, would you start with seating depth adjustment and then powder charge or vice versa? I have a comparator and am very familiar with Case to Ogive OAL. I realize that accuracy will be a process of adjusting both, one at a time but I am curious where you would start. Both of the guns are SAAMI spec chambers and mags.
Powder charge, and then seating depth
That is what I was thinking but then I was reading info on Berger's site and they talk about starting out close to the lands. I have always thought the shorter the jump the bigger the pressure spike, to a point. So this little bit of info may be causing me to over think this. Hence, my asking what some might think a simple question. Thanks for the reply.
In my opinion, there's no wrong place to start with seating depth as long as its effect on pressure is taken into consideration for safety's sake. That being said, you have to be willing to play with it some. I'd recommend increments of about 0.020" to a depth of up to about 0.150" off the lands or more to start, then fine tune based on what you see. I used to be very stubborn about finding seating depths in the 0.015" to 0.035" range, and I wasted a lot of components as a result.
Start at the lands (or at max magazine length) to find your optimum powder charge, then work back to find your best seating depth.
That way you won't be increasing pressure by seating longer looking for best seating depth.
Start at the lands (or at max magazine length) to find your optimum powder charge, then work back to find your best seating depth.
That way you won't be increasing pressure by seating longer looking for correct seating depth.
This.
Yep.
The only, relatively minor, warning is that when rifle bullets are seated VERY deeply, at some point pressures start increasing again. But that's generally around 1/2" from the lands, though it can start at around 1/4" with some cartridges, bullets and powder. But if you seat them deeper gradually, as when adding powder, you'll notice the velocity starting to rise.
On the other hand, most rifle/load combos will improve in accuracy long before bullets are seated even 1/4" from the lands, much less 1/2".
I haven't seen even factory loads at 1/2 inch from lands. Only ones I noted are Weatherbys that far from lands.
Start at the lands (or at max magazine length) to find your optimum powder charge, then work back to find your best seating depth.
That way you won't be increasing pressure by seating longer looking for best seating depth.
+1
I use to stress and pull my hair out working with seating depth. Now a days i always start at 0.010 off the lands and i've found that i can usually find a very accurate load by juggling powder and components and just leaving the seating depth at 0.010. The only exception I've had was working with Barnes bullets which were seated 0.050 off the lands and wouldn't shoot worth a darn any closer. Works for me.
I use to stress and pull my hair out working with seating depth. Now a days i always start at 0.010 off the lands and i've found that i can usually find a very accurate load by juggling powder and components and just leaving the seating depth at 0.010. The only exception I've had was working with Barnes bullets which were seated 0.050 off the lands and wouldn't shoot worth a darn any closer. Works for me.
This is what I do. Usually, once the seating depth is settled , finding an accurate load is much faster.
Bob
I use to stress and pull my hair out working with seating depth. Now a days i always start at 0.010 off the lands and i've found that i can usually find a very accurate load by juggling powder and components and just leaving the seating depth at 0.010. The only exception I've had was working with Barnes bullets which were seated 0.050 off the lands and wouldn't shoot worth a darn any closer. Works for me.
This is what I do. Usually, once the seating depth is settled , finding an accurate load is much faster.
Bob
If you are looking for the best accuracy, I don't see how settling on an arbitrary seating depth would be easier.
"Juggling powder and components" will cost more, in both dollars and time, than picking a known good powder and a common primer for the caliber being loaded and adjusting seating depth as required.
What is that magic formula? Kiss, find pressure, rock on?
If your hunting rifles are shooting -MOA, why are you playing with them? They seem to be shooting fine. The change from 500 to 600 is 2 MOA. Run your sight up and shoot...save a lot of BS.
What is that magic formula? Kiss, find pressure, rock on?
Easy said but lots of rifles on the market, you will find that the round will not fit in the clip if you seat that close to the lands. For ex my TRG in 338 Lapua, and my 300 WSM Benelli R1. Many more out there I'm sure.
Quoting an esteemed member's advice.
I had that issue on a big scale with a Win. M70 in 300 WinMag, and two of my .308s suffer that to a small degree when using some of the slicker bullets.
It's a matter of starting out at magbox confine and going from there. I've been lucky so far in that I've never had a problem putting an accurate load together, even if the jump is more than I really like, as was the case with the .300 WinMag.
I like to start at .010" off the lands and do a ladder test to try and find the nodes. I'll then pick a charge weight in the middle of the faster node, assuming I didn't get any pressure signs, and vary the seating depth to find the best accuracy. Generally it works with a rifle that wants to shoot.
Yep.
But if you seat them deeper gradually, as when adding powder, you'll notice the velocity starting to rise.
On the other hand, most rifle/load combos will improve in accuracy long before bullets are seated even 1/4" from the lands, much less 1/2".
Mule Deer, is this true only after you have seated way deeper past the point where pressure starts going back up
or is the opposite true when seating at normal seating depths, like from just off the lands to .250" or so?
Just got back to shooting after back surgery. I loaded several test loads starting with the heaviest charge I was willing to make with the longest COL. Turns out that my gun likes the one load that is the closest and the one that was the furthest away. Hated everything in the middle. Feel like I now have a solid starting point to fine tune the loads now. Thanks for all the advice.