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Deeangeo, here is the data that the gun maker supplied when I had my custom mannlicher made. The usual disclaimers apply, this worked in my rifle, it might not in yours, best, Mike

"Load Development (by Rocky Hays)

The customer requested hand loads using Woodleigh 160 grain Weldcore and Barnes 130 grain TSX bullets. When I do load development, I blueprint each case, uniform the primer pocket and flash hole, re-size and trim to length. I take portable loading equipment to the range, so I can load one round and shoot it. That way, the barrel is always cold when fired. In addition, if I have an unacceptable load, I don't have others like it. I shoot from a bench rest using a Lead Sled and try to hold the gun the same way for each shot. I record weather data and chronograph every shot. The idea is to remove all possible human and weather-induced variables.

I found one line of load data for IMR 4350 powder in an old reloading manual to use as a starting point. 36.8 grains was supposed to yield 2100 feet per second (fps) for the 140 grain bullet and 34.0 grains was supposed to yield 1900 fps for the 160 grain bullet.

The first load tried in the new rifle used 36 grains of Hodgdon 4350 powder and a 130 grain Barnes TSX bullet. Winchester primers and new Norma brass were used for all loads. The chronographed velocity was 2636 fps 10' from the muzzle. The fired primer showed signs of slight cratering, so experimenting with this load was discontinued.

The second load I tried was 34 grains of Hodgdon 4350 with a 156 grain Norma bullet. This chronographed at 2555 fps and showed the same slight primer cratering. Again, testing was stopped. I concluded that the old load data was essentially useless with modern bullets and powders in this rifle.

I reduced the minimum load to 32 grains of H4350 and fired 30 test rounds. I switched to Accurate 4350, which lowered the muzzle velocity by about 200 fps. The average 100 yard group size was 2-1/2" with either 4350 powder, which I regarded as unsatisfactory for this rifle.

I then tried IMR 3031 powder. This yielded an appropriate muzzle velocity of 2124 fps with the 156 grain Norma bullet and a 1-5/16" group size. Better accuracy, but still not what I was looking for.

I moved on to IMR 4895 powder. 28.8 grains yielded a 1", five shot group. IMR 4895 clearly agreed with this rifle. It should be noted that the maximum load with IMR 4895, according to the reloading manual, is 34 grains. I exceeded that muzzle velocity by 100 fps with 30 grains of powder.

The following trip to the range was to develop a hunting load using IMR 4895 powder. I used Woodleigh Weldcore 160 grain bullets and Winchester WLR primers. The results were as follows:

powder (gr) velocity (fps) avg. 100 yd. group std. deviation

28.6 2043 1-1/16" 217

28.8 2110 1" 107

29 2181 3/4" 69

29.2 2219 3/4" 104

29.4 2251 1" 207

29.6 2278 1-1/8" 125

29.8 2302 1" 114

30 2323 1-1/4" 181

The next range day was devoted to the Barnes 130 grain TSX bullet, with IMR 4895 and Winchester WLR primers:

powder (gr) velocity (fps) avg. 100 yd. group std. deviation

29.8 2094 fps 1-3/4" 69

30 2145 1-3/4" 71

30.2 2186 1-1/2" 57

30.4 2194 15/16" 62

30.6 2115 15/16" 53

30.8 2232 5/8" 14

31 2260 3/4" 64

31.2 2289 1-1/2" 87

31.4 2330 2-3/4" 106

It became obvious that pushing the 130 grain bullet much over 2260 fps in this barrel degraded the accuracy, perhaps due to the 1:8" twist. By the end of the third day at the range, I had fired nearly 250 rounds and had developed sufficient loading data for each of the requested bullets. The targets indicated I could switch between the 130 grain and 160 grain bullets without re-adjusting the scope.

Next, I loaded more of the selected loads with 130 and 160 grain bullets and shot both bullet weights at the same target to form a composite group. The 130 grain bullets produced a group that was centered 7/8" high and right from the bull's eye. The 160 grain group was centered 9/16" low and left from the bull's eye, which means that there was only about 1-1/2" between the centers of impact of the two bullet weights. Compared to the size of a big game animal, this is negligible."

Edited by Mike_Bailey (31/03/16 07:09 PM)

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