Long Distance Load Tuning

bkondeff · #1 07-24-2009, 01:00 PM

I have found a good load for my new Tikka SS 25-06.

52.0 gr IMR 4831, Berger 115, Fed 210, seated to touch, neck and bullet runout less than .002 ave. Velocity = 3040

Four initial groups at .90, .55, .44, and .25. The first of the string included a first shot, cold bore, fouling shot that was approx .40 from the other shots.

Now when I take this load out to 200 yards, my groups have been 1.60 1.90 and 2.1.

It may be me, but so far it seems that the groups are opening up. As I test at longer ranges, are their tricks anyone has found to tune. I already went through some seating and primer tests, but should I redo them at longer ranges?

jmason · #2 07-24-2009, 01:37 PM

Quote:

Originally Posted by bkondeff

As I test at longer ranges, are their tricks anyone has found to tune. I already went through some seating and primer tests, but should I redo them at longer ranges?

Do you have a chronograph? What's your es? for how many shots?

loaders_loft · #3 07-25-2009, 12:58 AM

are they opening up horizontally or vertically?

bkondeff · #4 07-25-2009, 06:17 AM

cloverleaf up close and a fairly even triangle at 200.

3fingervic · #5 07-25-2009, 07:50 AM

Were you talking inches? If so, those groups @ 200 yard seem pretty close to the MOA you were getting @ 100 yards. If I shoot .5" group @ 100 yards, I would expect to shoot a 1" group @ 200 yards. And that's if the wind isn't a big issue.

bkondeff · #6 07-25-2009, 02:29 PM

My point s that I went from basically .5 MOA load, to 1.0 MOA load from 100 to 200 yards. I didn't believe it was the wind or the equipment, though some portion may have been due to a relatively thick center crosshair on my Zeis Z-600 reticle.

At 200 yards I would expect to maintain closer to the .5 MOA with a goal of under or at MOA out to about 600 yards.

As it turns out I ran some more of my 52.0 grain 4831 loads and shot them at 100 yards again and got 2 groups between 1.5-2.0 moa. I'm sick. I had to bump the shoulder back a few thousands before this reload instead of just neck sizing and had a harder than expected time with the FL Die, as they seemed to want to stick in the die even though they where well lubricated. So much so that I actually stuck a die in. While the neck runout seemed to stay around .001", I think somehow the friction on the cases are the cause of this group as all else seemed well. I have ordered a Carbide sizing button and will run the rest of the brass with that and see if all is well again.

This can sure be frustrating.

Michael Eichele · #7 07-25-2009, 03:51 PM

It helps to tune your loads at the distances you intend to shoot and not worry about 100 groups. 100 yard shooting, testing and development has its place but as you are finding out, it can be frustrating.

Make sure your paralax gets adjusted from 100 to 200 yards when you move.

What bullets and twist are you using?