Well I guess it's not all bad.

It's about my load development hypothesis.

I thought it might be possible to:

1. Find the max velocity for your rifle

2. Load about 12 shells only varying the seating depth to tune it. Groups of 3.



It worked ok in my .243 wssm. I found a good load in 9 shots. I then tried to fine tune the seating depth by .005" on either side of the tested depth.

The tested depth was still the best.

I then tried tuning more but with charge weight. I loaded .3 grains on both sides of the first tested load.

The group that was loaded .3 grains higher tightened the groups up.



I did the test last week with my .300 win mag as well. I found a decent load. It grouped just over an inch at 200 yards. This week I thought I could push the velocity higher and did. With the higher velocity I couldn't tune the load to anything I liked with just the seating depth. I took the best groups by seating depth and then tried to tune with adjustments in charge weight (like I ended up doing with the .243 wssm). No luck


Even though I found a decent load, it still took some charge weight adjustments to make it as good as it could be with the .243 wssm.

I think that I got there a little faster though.

With the .300 win mag, The gun definitely shot better at the lower velocity with the bullet in question. It's possible it just doesn't like that particular bullet. It's a 165 gr SST. It shoots the 180 gr Accubond better. I may try again with a 165 Gameking............

Sometimes finding the perfect load is like trying to win the lottery.

Seating depth is important but it is only one of several variables.

At least you are getting good accuracy.

The good news is that you are working at it and keeping us informed! Thanks for all the interesting info you are providing! When I get my suppressor mounting sorted out, I will be applying your method to my 303-25. I started by finding a load that gives me 'enough' presure without overdoing it. The next step will be seating depth.

rca,
While I have some good loads I also have my share of loads that shoot great on a trip to the range.

The next trip I will shoot up the reminder of whatever I loaded and they do not perform anything like they did on the first trip.

It is sometimes amazing to get smaller groups with cast bullets in a tang sighted BPCR than with one of the better known scoped bolt guns.

I think it must be my lack of typing skills that is impeding my load development.

quote:

Originally posted by SR4759:
I think it must be my lack of typing skills that is impeding my load development.

Years ago while stationed in Montana with the Air Force (1988-1992), I loaded some 165 grain Game Kings in my 300 WM down to 30-06 velocity. I shot two deer with them and the bullets did not perform like I wanted.

The first shot went straight through the chest (not broadside) of a button buck at about 40 yards. When I gutted it, all I found were bullet fragments and no exit wound. Next, I shot a 4x4 whitetail buck broadside at about 60 yards as he attempted to cross a creek and escape me. The bullet exited and left what I initially thought was a new kind of Department of Fish and Game tag! What looked like a rivet on the offside of the hide was actually the bullet jacket. The jacket stayed in the hide while the core seperated and exited.

Some would argue and rightfully so, the bullets performed just fine. After all, I did kill and recover both deer. However, I wasn't satisfied with their performance so I switched to 180 grain Speer Grand Slams and 180 Grain Nosler Partitions loaded to 300 WM velocity and my problems disappeared. Some folks don't believe you need so-called "premium bullets" for deer and that's fine but I'd rather have em and not need em than to need em and not have em. Back in Montana, elk were also on the menu so stouter bullets were a good idea. I now live in Alaska and bears are on the menu so I now only use "premium bullets".