Advice please on my finicky .308...

[jb1000br]

Duff -- square to rectangular mark on the bullets from the lands is nice.

When you know you are in the lands you can keep seeting the bullet incrementally deeper till the marks go away. I personally prefer 20 thou in or off, not much in between.

When in the lands you will have to chase them as they erode, but it aint too hard.

Load up 3 rounds each of:

current depth
+0.003
+0.006
+0.009
and maybe 12thou long if it is more than a couple hundred rounds.

When you shoot these at 200yds or more you will see a nice pattern that will point to the best depth (large...then shrinking groups, then they'll open up again) pick the length with the best group.

My 6.5 did this one day at 200yds

+3thou = 0.075 (yea, 75thou)
+6thou = 0.210
+9thou = 0.700

I stuck with the 0.075 obviously.

IIRC, the 3 shot group at current depth was around .25 or so.

FWIW,
JB

 

[Bart B]

Rheinhardt, if you get in touch with anybody on one of the USA's long range highpower rifle teams and ask 'em about how they seat their bullets, you'll learn that they push 'em into the lands a bit. Even when the world championships are held and sample ammo is sent to everyone, they have their barrels chambered such that the bullets get pushed back a few thousandths when the bolt is closed.

Best accuracy has always happened when the bullet is pushed into the leade. Otherwise, it won't be as perfectly centered in the rifling when it starts moving down the barrel.

 

[jb1000br]

Bart -- us Long range BR people do it too...

I have always found best results in the lands.

Next load i develop will start at jam length...

YMMV,
JB

 

[billpock]

If your rifle fails to shoot well with these load recipes, I think it's safe to say that there is definitely a problem with the mechanics of the rifle...

Or your loading technique or equipment thats where the Gold Medal Match comes in.
BP

 

[green 788]

bp... point taken. /ubbthreads/images/graemlins/smile.gif

 

[GA1dad]

Re: Advice please on my finicky .308... *DELETED*

Post deleted by GA1dad

 

[GA1dad]

Guess I should've added 168 gr. Matchkings in front of 41 to 42 grs. IMR4895. Typically if a modern 308 will not shoot this load atleast decently,,,,there is something wrong.