Decided to give these little buggers a try in my Weatherby Vanguard. Maybe I should have checked the twist rate beforehand, but I didn't honestly give it a thought.

As it turns out, the Weatherby Vanguard is a 1:10", which is most suited to bullets of 100 grains or more.

Well, surprise surprise surprise...using Varget, the little 55gn bullets performed better than I anticipated. I decided to give the OCW method a go and I am pleasantly surprised with the results.

I selected 45.5gn as the maximum charge weight per the Nosler Reloading Data. This gave me a start point of 40.95gn which is 10% below maximum.

Using 1% increments for my loads, I loaded three rounds per increment, plus a few extras. Loads were:

Load..........Rounded off to:
41.35gn.....(41.4gn)
41.77gn.....(41.8gn)
42.2gn
42.62gn.....(42.6gn)
43gn
43.47gn.....(43.8gn)
43.9gn
44.35gn.....(44.4gn)
44.78gn.....(44.8gn)
45.24gn.....(45.2gn)

Headed off to the range to do some testing. Lovely day, very little breeze, so I was in a good way. Had a ball shooting, and was surprised with a couple of respectable groups...which gave me my load for this bullet. I have pretty much settled on 43.5gn of Varget as the Optimal load for this bullet...but the others aren't too bad either.

Have a look at the pic below and let me know if I selected the right one.

Don't think I will bother with any fine tuning...that's about as good as I will ever be able to shoot.

Cheers, Vince

Vince, The 43.9 load looks like it has the same lateral dispersion as the 43.5 but better verticle. I assume 45.2 was spread out more.

It only takes 2 shots to determine if its a bad load but several strings of 5 to confirm its a good load.

I'd recommend loading 15 more. 43.5, 43.7, 43.9.

In my experience, 3-shot groups are good indicators but they don't tell the whole truth about the consistency of a load.

Your twist isn't off for that bullet. I get a stability factor of about 1.7. Above 2.0 is where accuracy could be an issue.

I used to like the 243, they shoot flat like laser gun.

I would use either 43.5 or 43.9, mind you there is also human factor on the result on the target.
I would usually wait a few weeks and shoot them again.
It may be due to other circumstances that make the group changes.

I think that 43.9 looks like the one You might have pushed the trigger (rh) a little if it wasn't bagged solid

or the wind?

This is the full range of targets I fired On Monday.

The way I read the OCW 'instructions', you only need fire 3 shots per load to determine a load that is your start point for fine tuning. In this regard I believe the exercise I did on Monday is a screaming success.

Slim, you are correct about the final determination on a load by firing a number of 5 shot groups...which is exactly what I intend doing. I might even do a little fine tuning...a 1/10th of a grain either side just to see if it makes an appreciable difference.

You could well be right Fnuser. I was also the Range Officer on the day and I was back and forth up and down the range doing the usual safety checks etc, so my concentration might have been off a little, also the wind did pick up slightly towards the middle of the shoot, but not what I would cal significantly. I have to agree with your observation...user error mate...the Nut behind the butt was loose.

Cheers, Vince

The dimensions of the target are:

5" in diameter
rings 1/2" apart
Large outer red ring is actually two smaller 1/2" rings

Cheers, Vince

Targets 7, 8 and 9

Last one

So out of those targets, which one is the FIRST shot out of a COLD barrel?
Thats the important one.

None from a cold barrel mate...I fired three fouling shot before I started the groups. I allowed a few minutes between groups for the barrel to cool.

Cheers, Vince

I think when you get done you are going to have a tack-driver. A good example of the understanding that the OCW process can give. I definitely would shoot some more in 43.9. It the wind blew the third off to the right, this would be a great load if it can hold together for a 5-shot group!

Lookin good Vince It's always a great day when we can send some lead down range .

Great work Vince,
I've played around with the OCW a bit, and as with all things we adapt.
I just simplified the process for myself. Others may be offended, but....
Here goes.
Most of my loads seem to shoot best near max.
I only make up 18 rounds.
Start half grain over max and work back.
Making 3 rounds at each increment at the half grain mark.
My 4th edition ADI manual (heard there is a 5 now)
Max 45grn 2208 - start 41grn
My loads would be
3x45.5, 3x45, 3x 44.5, 3x44, 3x43.5, 3x43
and try those, I don't know if measuring out to the 1/100 of a grain at this point is either beneficial or easy.
Just my 2 bobs worth,
but it is fun trying to find that load that just makes 1 hole with 10 shots