.308 win seating depth

[vaeevictiss]

I have a question on seating depth. My rifle is a nearly stock 700 SPS Varmint, barrel cut to 22"(1:12 twist). My current load is a 178gr A-Max on 43.8gr of Varget in Lapua brass, with a OAL of 2.910.

Yea...that seems long but the rifle has a very long throat. That 2.910 is actually only .020 off the lands. Im shooting sub 1/2 MOA at 100yrds.

My question is i have been looking at these..

Berger Target Bullets 30 Cal (308 Diameter) 150 Grain Hollow Point

Ive been reading that the flat base bullets are better for the 100-300yrd ranges i usually shoot. the thing i am concerned with is the length.

the length of the A-Max is 1.325 so when seated to my length, there is .430 in the case.

With the Berger, its length is 1.172 so when it is seated there is only .277 inside the case.

Is that enough? or will i just have to seat deeper and be farther from the lands.


I also have no idea what my velocity is with that round, like i said it is nice at 100 yrds, but im thinking that is not enough powder...but when i shot my 44gr load during testing, something didnt "feel" or sound right so i stuck with the 43.8.





thanks for any help.

 

[melloyello]

I would think 43.8gr would put you pretty close to 2500-2550 range. That's looking at numbers from my aac-sd and an average looking at that charge on many different forums.
I know exactly what you are talking about when you say deep throat. Mine works out to 2.935" touching the lands with 178gr amax. My magazine will only go to 2.860" so I don't worry about loading that far. out. I personally wouldn't load those shorter bullets out that far. I would check the .308 loads quoted on this forum in another thread(forget what it's called right now) and see if anyone else is loading those that far out.

 

[vaeevictiss]

Yea i guess I should have posted in the new reloading section. Damn changes haha.

 

[gvanhyning]

When I was loading for a factory barrel I didn't worry about how much the bullet was jumping. The fact that your max COAL is determined by the magazine length, unless your going to shoot single shot, is the limiting factor. If you change bullets then you go back to square one on load developement. When I build a load I start the COAL at max magazine length and find the charge that groups best and then play with the seating depth to tighten the groups. If you're looking at Berger in the 150 grain range consider the 155.5 Full Bore. The bullet is very forgiving with regard to jump. Good luck.