Mauser M03 - Barrel Change

I made a short video on the weekend showing the 6.5x55 Match barrel being removed and the 243 Winchester barrel being installed. The Kahles K624i scope is then reinstalled to the receiver. I had loosened the two barrel mounting screws before starting the camera. They were as 'hand-tight' as I could get them, so getting them loosened was a bit of a trick. I don't use a torque wrench; I just tighten by hand, as consistently as I can, with the Mauser T-key. It seems to be working as the 243 barrel dropped two rabbits with the first two shots, at 230 meters. :-)

Mauser M03 + Kahles K624i + Rabbits

This is a quick mobile post from yesterday's outing. With the first shot from the 6.5x55 barrel, cold & clean, I dropped the rabbit seen through the Kahles. Same again with the next two shots, all at 250m. Later in the day I installed the 243 barrel and hit at 230m with the first shots. Very happy with the repeatability and accuracy of the Mauser M03 system.

Mauser M03 Deluxe in 6.5x55 with Kahles K624i riflescope

The view through a Kahles K624i scope with MSR-K reticle

With the 6.5x55 & 140gn Nosler Accubonds,
better velocity from 46gn of 2209.

Mauser M03 - Chronographing 6.5x55 Loads

In the video linked below I'm firing 6.5x55 hand loads over a chronograph. The idea is to use the velocity and ballistic coefficient of the projectile to work out the ballistic curve, for long range shooting. But I think I'll be working the load up to a higher velocity, which hopefully will help improve the group size too - often does. These loads were Lapua cases and 45 grains of 2209 pushing Nosler Accubond 140 grain bullets. The average velocity from the 60cm barrel was 2667fps. The group size is 24mm; not as good as the 12.5mm three shot group from the previous week.

Lapua Cases - 243 Win & 6.5x55

I'm developing hand-loads for my Mauser M03 barrels in 243 Winchester and 6.5x55 calibers. The pictures below show the spread of weights for new Lapua cases, in 0.1 grain groupings. 

The 243 cases are in a wide, peaky, skewed Bell curve distribution; the mode is 171.3gn. Can you see the case that is fifth from the end of the long column? Even the best cases come with dings.

The spread for the 6.5x55 cases is not as wide, but isn't a neat Bell curve either. The mode for the 6.5 cases is 179.2 gn. It's an unusual distribution, which almost suggests the cases are from two batches.

I need a volunteer to do this with a thousand cases, to see if the curves get neater. :-)

Lapua 243 Winchester cases, sorted into 0.1 grain groupings. Mode = 171.3gn.

Lapua 6.5x55 cases, sorted into 0.1 grain groupings. Mode = 179.2gn.

Mauser M03 - Accuracy - 243 Win & 6.5x55

It was a beautiful spring day yesterday, though the wind picked up a little in the afternoon while I was doing some load testing with my Mauser M03 Deluxe and two barrels - a standard profile 243 Winchester and a match profile 6.5x55. The video below shows a group from the 243 and then the first three shot group from the 6.5. I'm quite happy with how these barrels are working. The target board I'm using, the same as in my earlier videos, shows how hand loading is delivering better results than the factory ammunition used with my 270 Win and 30-06 barrels. I'll be developing hand loads for those later.

The 243 load uses 95gn Berger VLD Hunting and 42gn of 2209.
For the 6.5x55 it's 140gn Nosler Accubond and 45gn of 2209.
Lapua cases and RWS primers for both.