Help decipher my ladder test.

[IA_shooter]

Did a ladder test today @ 305 yards. Shooting off of my Stable Table. Bipod in front, bag in rear. What do you make of the results? 308 shooting 168 gr A-Max with Varget. Started at 44.0 gr, 44.4 gr went lower, 44.8 gr went lower still, and then 45.2 gr jumped back up higher and 45.6 gr and 46.0 gr went higher each time as well. 46.0 gr POI veered to the right on both sets for some reason. The two 45.5 shots were left overs from a previous group test so I just shot them both on the right area as well. I'm thinking that the sweet spot might be in the 44.2 gr to 44.6 gr area? Do you think I'll possibly hit another node above 46.0 gr? Thoughts?

 

[DHuffman]

Unless your on a "need for speed" chase I would shoot the 44.0-46.0 range again in three shot groups. Is there a chance you mixed up rounds? There looks to be a node between 44.4-44.8 on the first string then on the second string it appears to be between 44.4-45.2 then 45.6 looks very good also. I think above 46 much and you'll be encountering stiff bolt lift if your savage is anything like the two I have.

I think I would explore those 3 nodes and use a smaller jump between charges to find the middle of each node using three shot groups.

I have two of those model 10 savages that shot 3 shots into 1 hole with that bullet and 43.5 grains Varget

The 44.0 being higher on both strings would be barrel harmonics or whip in IMHO

A lot of guys will disagree with me but I do my early load development @ 100 yards to help take "me" out of the equation.

Just my 2 cents worth!

 

[effendude]

Ditch the portable bench, get on the ground or a permanent bench. Get a level on your scope. Be honest with yourself on evaluating how each shot broke. Load three of each powder charge, shoot increasing charges at a target, then start over on the second and third target to attempt to determine a pattern. One test is not enough.

Scott

 

[kevinbritvec]

Brass used?

I consider 46.0 grains of Varget a maximum load with 155 grain match bullets. I would be looking at a range between 42.0 and 43.5 on the high end when loading Varget with 168 grain match bullets. These loads would be tops for me in Winchester or Lapua brass.

Lake City military surplus brass would be maximum closer to 41.5/42.0 grains to reach maximum pressure.

Double check your scope base and rings to insure they are tight. I would group shoot at least five rounds each starting with 42.0, 42.5, 43.0 and no more than 43.5 grains. Not seeing pressure signs is a good thing, but by the time you do see pressure signs you're probably over 70,000 psi.

 

[IA_shooter]

I went back and shot groups with 44.4, 44.6, 44.8 and 45.0 grains and the 44.6 shot best so I took it out to 200 and got this with it.........

.....took it out to 400 yards and shot 3 different groups that were 1-3/4" average and just today took it out to 600 yards and shot a 3 shot group of just under 2.5" so I think I'm sticking with this load.

 

[YEW PLUCKER]

Barrel harmonics are always in play. You will never know exactly where the tip of your barrel is in space at the moment it releases the bullet. Different loads will create different vibrational patterns. Each one will cause the muzzle of barrel to be at a different point in space relative to your platform, at the moment it releases the bullet.

 

[dkhunt14]

Brass used?

I consider 46.0 grains of Varget a maximum load with 155 grain match bullets. I would be looking at a range between 42.0 and 43.5 on the high end when loading Varget with 168 grain match bullets. These loads would be tops for me in Winchester or Lapua brass.

What is maximum in your rifle and his could vary an awful lot. The barrel, freebore, bullet used and lot of powder used can change this amount by way more then a grain. Matt

 

[DHuffman]

I went back and shot groups with 44.4, 44.6, 44.8 and 45.0 grains and the 44.6 shot best so I took it out to 200 and got this with it.........

.....took it out to 400 yards and shot 3 different groups that were 1-3/4" average and just today took it out to 600 yards and shot a 3 shot group of just under 2.5" so I think I'm sticking with this load.

Outstanding! I think you owe it to yourself to try 43, 43.5 & 44 all my savage model 10 .308s shoot that 44.5 load good and there is a good node @ 46.5 as well however the node @ 43.5 is better than both higher nodes accuracy wise.

 

[IA_shooter]

Outstanding! I think you owe it to yourself to try 43, 43.5 & 44 all my savage model 10 .308s shoot that 44.5 load good and there is a good node @ 46.5 as well however the node @ 43.5 is better than both higher nodes accuracy wise.

I'll take that into consideration. Thanks.

 

[escopeta]

My Tango 51 runs best with 42.5 of Varget and 168SMK. Lapua brass. Runs 2650 out of 20" barrel and under .3" @ 100.

 

[SHootSTraight22]

44.0-45.2gr needs to be shot now in a OCW type test using .2-.3gr increments... This is what I would do.. Try that and post the pics of the targets...

 

[Rtheurer]

Brass used?



Lake City military surplus brass would be maximum closer to 41.5/42.0 grains to reach maximum pressure.

Is this fact or just rumor past on over the last two decades. The reason I say this as the last Lapua brass I measured on a lab scale balance for internal capacity and some LC 85 Match Brass was within .3 of a grain of internal Water capacity of each other. Not saying its not a good idea to pass along the thought that LC brass " Could" have less case Capacity. Its not always true like most old wives tail's passed down over time. Not trying to be critical or an Ass hat,Please don't take it that way, just an observation of actual testing.
Hope all is well
Russ T