Need help finding a new load for my custom build .308

[shawscar17]

Hey guys, so I am just about a week away from my custom build (.308) being completed and having to start finding a new load that will work with the new set up. As you guys know finding components is freaking hard these days so this is what I have as far as bullets and powder: 4 boxes of Nosler Custom Comp. 175 gr (BC .505), 1 box of SMK 175, 2 boxes of Hornady match HPBT 178 (bc .530). Powders are as follows, 3.5 lbs of Varget, 8 lbs of Pro 2000 MR.
Now my rifle was a Remington 700 sps varmint, now it has been trued and blueprinted and has a Bartlien barrel on it, M24 contour, 1-11.25 twist rate, and 26 inches long.
I developed a load for my friends rifle a Remington 700 target Tactical that has a barrel with a 1-11.25 twist, 24 inch barrel, rate using SMK 175 and 46 gr. of varget, .01 off the lands and that shoot great! Just not sure about using the Hornady 178's and Pro 2000 MR.
Anyone out there find a load that works well with the Bartlien 1-11.25 barrels? Thanks for any input just trying to save myself some time in the workup, I hate trying to find a load. I have only like a month to break it in and find a load then I am shipping the rifle to FL for a training and I need it done before then. With working full time and two little ones any help saving me time would be greatly appreciated.

Sean

 

[Deadshot2]

It's tough to develop a load with the lack of components that exists today.

I have found that my rifle which sports the 1:11.25 twist seems to really perform well with a 175 gr Nosler Custom Comp, Sierra SMK, or the 178 gr A-Max when it's pushed at a speed of 2550 to 2600 fps. I get there with 43.5 gr of Varget, 42.5 gr of IMR-4064, 46 gr of CFE223, and 41.5 gr of IMR 8208 XBR.

Over the last few years I've plotted accuracy nodes and speed with all the different powders I've played with and found that all I need to find a good starting point is to extrapolate a starting load from the manufacturer's data that gives me that 2550-2600 fps speed. Some slight adjustments from their are all that's needed. After the initial ladder test to find the barrels accuracy node, with every shot being over a chronograph, your rifle's "personality" is pretty well revealed.

If you want a good start load for the powders you listed I'd use 43.5gr Varget and load as long as your magazine will allow. If you don't mind single loading then go out to a 15-20 thou jump.

For the Alliant, I'd run a ladder test first and see where the higher speed nodes fall for your barrel. Start at around 45 gr and max at 47, single shot each load, increasing by .3 gr with each shot. This will show you where your barrel has sweet spots. If you have to reach out a long distance go with the higher node. If 800 yards or less is good, then go with the lower/slower one. Better brass life and often far more accurate.