Thread: Bullet seating depths

My process used to be load up groups of 3 rounds at 3 thou increments around my initial seating depth & shoot them. Worked fine most of the time provided you were in the window of what the projectile/rifle liked to begin with but sometimes involved a fair bit of shooting to get to the final load that worked & in todays climate as far as components its not ideal.

Now days i take my press & seating dies to the range with me. Ive bolted my press to a length of timber so at the range i can G clamp it to a bench to use it. Once i have done my powder charge ladder test & have decided on a charge, ill load up something like 24 rounds at home & seat them all at the longest COAL i plan to run. At the range ill put a couple of rounds through to warm things up/foul it if i have cleaned it, then start shooting groups. Ill fire 2 shots, if i know there was no operator error and the 2 shots arent within the group size im looking for i move on, firing more shots at that same seating depth isnt going to magically get better, just waste components and barrel life. To start with ill make bigger adjustments (6 thou at a time). Shoot 2 more at 6 thou less, if theyre looking good a 3rd. Repeat this process untill i find something that looks promising. When ive found a seating depth that looks promising, lets say 2.688. Ill seat 3 rounds to 2.691, 3 at 2.688 and 3 at 2.685. Shoot them and see how things look. Maybe even 3 at 2.682 to see how far the window goes. If its looking good and consistent / group size im after, ill seat a few more at the depth that worked best, Shoot some more to confirm im happy with it and job done.

Has definitely helped me save components + time by having my press at the range with me and being able to do whatever i want on the fly. If something looks good, can try it again straight away to confirm rather than going home and wondering if thats gonna be the load till you next range trip, or going home loading a bunch at that seating depth only to find next range trip it was just a fluke.

Originally Posted by 6.5 CRD

My process used to be load up groups of 3 rounds at 3 thou increments around my initial seating depth & shoot them. Worked fine most of the time provided you were in the window of what the projectile/rifle liked to begin with but sometimes involved a fair bit of shooting to get to the final load that worked & in todays climate as far as components its not ideal.

Now days i take my press & seating dies to the range with me. Ive bolted my press to a length of timber so at the range i can G clamp it to a bench to use it. Once i have done my powder charge ladder test & have decided on a charge, ill load up something like 24 rounds at home & seat them all at the longest COAL i plan to run. At the range ill put a couple of rounds through to warm things up/foul it if i have cleaned it, then start shooting groups. Ill fire 2 shots, if i know there was no operator error and the 2 shots arent within the group size im looking for i move on, firing more shots at that same seating depth isnt going to magically get better, just waste components and barrel life. To start with ill make bigger adjustments (6 thou at a time). Shoot 2 more at 6 thou less, if theyre looking good a 3rd. Repeat this process untill i find something that looks promising. When ive found a seating depth that looks promising, lets say 2.688. Ill seat 3 rounds to 2.691, 3 at 2.688 and 3 at 2.685. Shoot them and see how things look. Maybe even 3 at 2.682 to see how far the window goes. If its looking good and consistent / group size im after, ill seat a few more at the depth that worked best, Shoot some more to confirm im happy with it and job done.

Has definitely helped me save components + time by having my press at the range with me and being able to do whatever i want on the fly. If something looks good, can try it again straight away to confirm rather than going home and wondering if thats gonna be the load till you next range trip, or going home loading a bunch at that seating depth only to find next range trip it was just a fluke.

This ^^^ is exactly what I do for the same reasons.
I have tried the berger 30thou seating test twice for good results also as I've shown on a different thread before. However you are giving up alot of case capacity very fast going in at 30thou at a time.

Originally Posted by Roarless20

This ^^^ is exactly what I do for the same reasons.
I have tried the berger 30thou seating test twice for good results also as I've shown on a different thread before. However you are giving up alot of case capacity very fast going in at 30thou at a time.

Pretty much follow this start off at 20 thou or mag length for powder test/pressure.

Sometimes try out to 120 thou, also depending on how projectile
sits in case, I.e not sitting right out or jammed in.

Have a small RCBS partner press that can take to range with box of preloaded max length loads. Once fine tuned 3 thou increments(also push past node) you just push rest down to your desired length.

3 thou change in bullet seating depth can make a big difference in group size in an "accurate" rifle, I'm talking 1/4" or less agging rifle here.
If a rifle is only grouping around 1/2 - 3/4" then you probably won't notice the difference a 3 thou seating depth change will make.

With my hunting rifles I use 10thou changes to find the general seating depth the rifle likes then once I find that the seating depth changes are less to fine tune the load.

The biggest tuning help is a solid front rest and rear bag, I'm trying to shoot the best groups the rifle is capable of, not find out if I can shoot
Another thing you should use is something to tell you what the wind is doing, if you aren't using something to indicate what the wind is doing it's like aiming the rifle closing your eyes and pulling the trigger. a simple bit of ribbon on a stake is better than nothing.