AI AT 308 Load Development

[Mareshow]

Starting to do some load development for my AI AT and am wondering what everyone is doing for distance off the lands? As well as powder? I'm using 175 gr SMK and 175 gr Lapua Scenars. The last 308 I did some development for was a Remington 5R that liked to be 30 thou off the lands. any tips for AIs?

 

[Supersubes]

The AI barrel isnt unique in any way. Since .030 works in just about everything, it should work in your AI.

 

[nn8734]

There is literally billlions of gigabytes of load data/info on 308 all across the net.

What brass, powders and primers do you have on hand? Varget, IMR4064, RE15 are the go to for me.

Smks arent jump-sensitive (don’t think the scenars are either). Bullets are jumping .075” for each of my .308s . Chasing the lands isnt necessary for the bullets you will be using.

 

[AIAW]

Pretty much what was said above. The make/model of the rifle doesn't matter - every barrel is unique in it's own ways.

Ladder test with Varget - you'll find something pretty easily. Below is my MAX CHARGE on a Berger 175g VLD touching.

FEDERAL 210 Varget 43.5g

 

[whatsupdoc]

You can load 175SMK .020 - .030 from the lands with some IMR4064 or Varget and it should shoot just fine.

 

[Mareshow]

I understand there is lots of load data but I was looking at experience from other AI owners. Reason being I know that a lot of rifles from manufacturers appreciate the same thing or have similar accuracy nodes.

I was simply looking to short list my ladder testing, looking at what AIAW said I would start 2 gr below that charge and work my way up.

 

[Criver600]

Ladder nodes depend on your barrel, I've shot thousands of rounds of .308 through AI rifles loaded to 2.8 OAL, Win brass, Federal 210GM primers and Varget.

 

[ShtrRdy]

For those of you that load a 175 SMK and Varget for the AI AT, what velocity did you end up with?

 

[AIAW]

For those of you that load a 175 SMK and Varget for the AI AT, what velocity did you end up with?

2701 fps on a 26"

I can push them harder but the ES creeps slightly, along with slight primer cupping.

 

[918v]

I understand there is lots of load data but I was looking at experience from other AI owners. Reason being I know that a lot of rifles from manufacturers appreciate the same thing or have similar accuracy nodes.

I was simply looking to short list my ladder testing, looking at what AIAW said I would start 2 gr below that charge and work my way up.

What components do you have?

 

[Sogan]

Every barrel is unique. Every AI .308 barrel can be different. Do your normal work up all thought I will say I have an AI and it likes varget anywhere from 39.8-44.5. All about the same grouping and I was picking over minor differences

 

[ShtrRdy]

Every barrel is unique. Every AI .308 barrel can be different. Do your normal work up all thought I will say I have an AI and it likes varget anywhere from 39.8-44.5. All about the same grouping and I was picking over minor differences

With the 175 SMK?

 

[GIXXER2000]

When i had my AI-AT IN .308 26in 1-10 twist it shot 175smk, 175scenar and 178Amax all very well. My powered of choice is Varget but both IMR 4166 and 4064 work well. I like the 4166 better seemed to be less temp sensitive. The powder charge was within .2 of a grain Varget Vs 4166. From what I saw if you can't get Varget then try 4166 it has been easier to find.

 

[nn8734]

My buddy’s AI AEmk3 likes 41.7g IMR4064 in a LC LR case, WLR primer all under a 175 smk. He runs a 16” 1/12 AI barrel.

 

[Mareshow]

What components do you have?

I have 175 gr projectiles aformentioned, federal match primers and as far as powder goes stuff that may work is:
Varget
CFE 223
H4350

I have a few other powders as well but not sure how well they'll do in 308

I'm thinking maybe grab a pound of IMR 4166 and IMR 4064 as they seem more available than varget around here. Hate to do a load up and run out of powder

 

[918v]

CFE will get you the most velocity and same accuracy as Varget. I got 2800 FPS with 175SMK in my gun (24”). Interestingly, even though CFE is temperature sensitive, it’s zero shift associated with temperature changes offsets the change in velocity.

 

[AIAW]

CFE will get you the most velocity and same accuracy as Varget. I got 2800 FPS with 175SMK in my gun (24”). Interestingly, even though CFE is temperature sensitive, it’s zero shift associated with temperature changes offsets the change in velocity.

Damn, 2800 fps is moving nice. I don't believe I have ever tried any CFE.

 

[Huskydriver]

For those of you that load a 175 SMK and Varget for the AI AT, what velocity did you end up with?

Uh depends on barrel length...I don't own any 308s longer than 18" barrels

 

[FisherT&C]

IMR 4350 is an old trusty with 175s in a .308 Win.

 

[Mareshow]

I had a 10 kmh diagonal wind while doing these so not ideal but I couldn't wait to try. Looks like they all did really well with the 4166 42 gr showing the most promise. CFE 223 was meh so I didn't even label it. I'll try some 5 round groups next. Needless to say I'm pretty happy with the result so far.

I did a couple 5 shot groups at 200 yds with 185 gr GMM and was shooting clover leafs so for back up I'll just buy a couple boxes of that as well.

 

[shoot4fun]

Maybe I am an "outlier" but I have always loaded the 308/175SMK with 44.5 grains Varget and Federal GM primers in Lapua brass. I load them out to just fit for reliable in the AW mag. I've used this one in everything from GAP chambered, AINA chambered and AIUK chambered barrels without ever piercing a primer and have managed a dozen firings on brass without failure.
Disclaimer: While it works for me it may not for you so back down a couple grains and work up.
Currently I shoot the 185 Hybrid/Varget combo in my 10 twist AW and the 155 Scenar/IMR4166 combo in my 12 twist UK barrel.

 

[MK20]

41.7 IMR 4064
FC or LC case
FGMM primer
175 SMK.

With the FC case that is the dtic spec for MK316 Mod 0

 

[MK20]

Here you go.

 

[AIAW]

Here you go.

View attachment 7633205

If you divide the total quantity of powder by the charge weight of each the powder order of 889 pounds is dead nuts on so that's good!

That $12,500 toilet seat evidently isn't being laundered in munitions requisitions.

 

[NukeMMC]

Just an FYI ... Federal Gold Medal Match GM308M2 that I have measures 2.790" COAL and a Base-to-ogive of 2.220". For my AIAX barrel, that's about 0.050" of jump. It shoots light-out. SMKs are notoriously jump-tolerant, which is why Uncle Sam uses the crap out of them for Match and sniper ammo. Every barrel is different and every chamber is cut a little differently. The SMK design is the most forgiving to these differences for DoDs purposes.

 

[Sniperwannabee]

Reloading Depot

Open discussion on reloading, *always exercise caution* when reloading

www.snipershide.com

 

[81sfo]

 

[81sfo]

In my Aw 762 UK barrel i found two good accuracy nodes. 175-178 grain smk 41.7 imr4064 Lake city LR brass , and 175-178 gn and 44.5 imr4064 in Lapua brass.