.308 groups

[aorams]

Good Morning reloaders!

I am a new reloader and have recently started testing loads for a new Sako Finnlight in .308. Attached are the pictures of the groups (sorry, they are unlabeled in the photo) shot. The recipe is:

Nosler Brass
Federal 210M primer
Varget 44 to 46 gr in .5gr increments
Nosler Accubond 165gr

i have a Finnlight in 300wm and shoot 180 grain Accubonds with 80 gr of H1000 that shoot 3/4” or less consistently, so Im feeling pretty good about shooting technique.

Any thoughts on where to go from here? I’m only interested in using hunting bullets for deer and elk. Max range is 400 yards.

an additional picture of the 300 WM group is included for comparison

thank you!!

 

[Mule3006Elk]

None of those groups are terrible. Good: They have very good elevation control. Bad: not as tight as you would like. Assuming your seating 0.02 of the lands? Commonly, once your pick a load, playing with seating depth can get you dialed. For example: 0.025, 0.03, 0.035, etc.

I shoot Barnes. I tend to max velocity because monos need good velocity to open up. I adjust seating depth, 0.01 at a time, until I get good groups. Barnes are a little different in that they like a lot of jump. For this reason I use 0.01 increment when testing not 0.005 increment.

 

[N2TRKYS]

There’s not enough info given to tell you what to do next. What was the SD/ES for each load? Velocity for each load?

 

[aorams]

None of those groups are terrible. Good: They have very good elevation control. Bad: not as tight as you would like. Assuming your seating 0.02 of the lands? Commonly, once your pick a load, playing with seating depth can get you dialed. For example: 0.025, 0.03, 0.035, etc.

I shoot Barnes. I tend to max velocity because monos need good velocity to open up. I adjust seating depth, 0.01 at a time, until I get good groups. Barnes are a little different in that they like a lot of jump. For this reason I use 0.01 increment when testing not 0.005 increment.

Thank you! These loads are .083 off of the lands. OAL of 2.829. We were told by Nosler that accubonds like a lot of "jump".

 

[aorams]

There’s not enough info given to tell you what to do next. What was the SD/ES for each load? Velocity for each load?

I have not chronographed these loads yet. Unfortunately, my range is not very chronograph friendly. my past practice has been to find what load groups best first then shoot it through a chrono to find the velocity. I think a magnetospeed is in my future

 

[BBob]

Thank you! These loads are .083 off of the lands. OAL of 2.829. We were told by Nosler that accubonds like a lot of "jump".

"like a lot of jump" is a wide open nebulous statement. You might get lucky but just giving a bullet "a lot of jump" probably isn't going to give you your best. This from Berger can apply to any bullet: https://bergerbullets.com/how-do-you-load-and-tune-a-vld-bullet/

 

[aorams]

"like a lot of jump" is a wide open nebulous statement. You might get lucky but just giving a bullet "a lot of jump" probably isn't going to give you your best. This from Berger can apply to any bullet: https://bergerbullets.com/how-do-you-load-and-tune-a-vld-bullet/

Thank you for this. I will concentrate on OAL. Should I just take the best performing load and use that one?

 

[N2TRKYS]

I have not chronographed these loads yet. Unfortunately, my range is not very chronograph friendly. my past practice has been to find what load groups best first then shoot it through a chrono to find the velocity. I think a magnetospeed is in my future

I shoot all my reloads over a chrono. Otherwise, I wouldn’t truly know what’s gonna be accurate down range.

I find that Nosler’s tested COAL to be pretty much dead on for all the cartridges/rifles I load for.

 

[Mule3006Elk]

Thank you! These loads are .083 off of the lands. OAL of 2.829. We were told by Nosler that accubonds like a lot of "jump".

For Example, I'm working up a load for Edge TLR 175 grains. Factory ammo is 0.07 off the lands. Didn't shoot all that well for me. I'm started from scratch. I have some loaded 0.02 off the lands. I will work backwards from there.

As others have states having a good ES is important. Although plenty of reports of loads with not so great ES that shoot really well at distance. Sometimes you just don't know. However, it's more than reasonable and will likely save you time, if you put most of your effort into loads that have a good ES.

 

[aorams]

For Example, I'm working up a load for Edge TLR 175 grains. Factory ammo is 0.07 off the lands. Didn't shoot all that well for me. I'm started from scratch. I have some loaded 0.02 off the lands. I will work backwards from there.

As others have states having a good ES is important. Although plenty of reports of loads with not so great ES that shoot really well at distance. Sometimes you just don't know. However, it's more than reasonable and will likely save you time, if you put most of your effort into loads that have a good ES.

Thank you again! I'll get back to it with this in mind.

 

[dwent]

One thing you might not have considered and that you should be aware of while developing your hunting load, is that many bullets like to be jammed. If you are coming from the world of precision rifle competitions, while cartridges are seldom removed from the chamber before being fired, this is not a problem. However, unseating a bullet jammed in your chamber can be a hunt ending experience. My rifle seems to shoot its best will a little bit of jam, but for hunting loads where I don't want even the smallest possibility of dealing with an action full of powder, I choose a depth that is second best, but not jammed.

Like powder charges, there seems to be nodes with seating depth as well. I have found acceptably accurate nodes with as much as .040" off the lands and loads that were just as accurate at .002"

If you don't have a bore scope, I would highly suggest picking up the $40 one off amazon and getting in there and making sure you don't have a big old carbon ring in there at the throat, which can substantially affect where you think you are seating in relation to the lands.

You might also pick up a concentricity gauge. I cull out any rounds that have greater than .002" of bullet run out and just use those rounds for practice.

There are endless rabbit holes you can follow in the quest for accuracy. At the end of the day you have to decide what you are trying to accomplish. For me, I want a reliable load that I can pretty consistently shoot 100 yard three-shot groups between .33" and .5"

I am by no means an expert in this field. These are just a few things I've picked up a long the way that have helped me get enough accuracy out of my reloads to make it worthwhile over factory hunting ammunition for me.

 

[aorams]

Just wanted to follow up with those who responded and say thank you! Turns out my issue may not have been load development but instead trigger pull/weight...

went back to the drawing board with factory ammo and a lighter trigger pull and got sub moa results. Now load development is going better!

Thank you!

 

[Stefan]

For your reading.

Bullet Jump: Is Less Always Better?

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