I just thought I would post my recent results of working with my 9.3x62. I'm not doing near the amount of load testing that Ku-dude is doing, but I thought I would add my results to the thread.

Date: Nov 19, 2004
Cartridge: 9.3x62
Firearm: CZ 550 American
Scope: Leupold VX-II 1-4x
Barrel Length: 23.6" (60 cm)
Bullet: Prvi Partizan
Bullet Weight: 285 (18.5g)
Powder: RL-15
Powder Weight: 58.0
Case Make: Graf
Primer: WLR (not magnum)
C.O.L.: 3.29"

Chronograph
Shot# Velocity fps
1 ___ 2,317
2 ___ 2,320
3 ___ 2,327
4 ___ 2,314
5 ___ 2,319
6 ___ 2,307
7 ___ 2,309
8 ___ 2,299
9 ___ 2,314
10 __ 2,318


Summary
Average Velocity: 2,314 fps
Energy: 3,389 ft lb
High Velocity: 2,327 fps
Low Velocity: 2,299 fps
Extreme Spread: 28 fps
Standard Deviation: 7 fps
Coefficient of Variation: 0.30 %

(Coefficient of Variation = std deviation / average velocity)
(Just a handy ratio for comparing one load to another.)

This load was very accurate with a couple of 5-shot groups hovering right around 1 inch or so. Velocity is on the mild side but still within 9.3x62 velocity specs. (If I remember correctly, Kynoch/ICI loaded their ammo to 2250 fps. Sellier & Bellot currently loads to a spec of 2280 fps.)

For those of us in the USA, the 9.3 Prvi Partizan bullets are available at Grafs at very attractive prices. ($18.99 per 100) I was very pleased with the accuracy of this bullet considering their price. Should make a great practice load and it would probably work just fine on hogs down here in Texas.

-Bob F.

Saturday, I completed the third part of my experiments by examining the 286gr Nosler and Varget.

Having determined the reasonable limits for the 270 Speer with H4895 and Varget, and the same for the 250 Nosler Ballistic Tip, the next task was to determine what the limits would be for the 286-grain bullets. Prior to beginning the experiments I had concluded based upon my work with the 270 Speer that the charge of H4895 I was using to get just at 2400fps was too much. I limited my consideration to Varget, with which I was already working, and RL-15.

I loaded five Lapua cases with 60 grains of RL-15 primed with a 210M primer under a 286 Lapua Mega. This load is over the maximum stated in most manuals; however, based upon my experience with this rifle, I concluded that this would be an appropriate starting charge. The velocity was 2295fps, indicating that it would take approximately 63 grains of RL-15 to achieve a velocity of 2400fps. The work done with the 270 and Varget indicated that Varget was probably a better choice that RL-15 to powder this weight bullet.

Therefore, after the initial firing, I switched to Varget. In addition, I also concluded that the Partition bullet was probably the best choice of bullet based upon the velocity envelope at which it will reliably expand (1800fps and up). I commenced loading the 286gr Partition with 59 grains of Varget and the 210M primer. I seated the bullets to the same depth for which the stem was set for the 250-grain Ballistic Tip because I was also loading the last of that test series. The initial tests at this weight consisted of two series of five, which produced a average velocity of 2333. There were no signs of pressure, so the charge weight was increased to 60 grains and another series of five was fired. This produced an average velocity of 2360 and no signs of pressure problems. Finally, a charge weight of 61 grains was reached, which was for purposes of extended testing taken as a maximum. Another seven series of five shots was prepared and fired that produced an average velocity of 2393. Again, no indications of pressure were identified.

Upon the conclusion of the this test, the Lapua brass used had been fired once with RL-15, two times with 59 grains, one time with 60 grains, and seven times with 61 grains of Varget, or a total of eleven times. At this point, one of the cases was sectioned. Examination of the case walls revealed no indications of case separation and the primer pockets were as tight was they were when I started the test.

As with the other two bullet weights, the accuracy was good at all velocities, and frequently increased with velocity. The last five shot group was approximately .75" center to center, in one elliptical hole, which reveal upon examination, three bullets through one hole and two through another near by. The other groups were large holes approximately an inch in diameter, center to center, with an occasional flier, which I consider "operator" error.

The temperature during the test was the lowest we have had, starting at between 45 and 50 degrees Fahrenheit, and ending the day at approximately a high of 65-70. Varget is one of the extreme powders from Hodgden, and is suppose to exhibit a low variance to temperature. However, I will be using these loads to hunt dangerous game in weather that may reach the upper seventies or better. I could see no reason to move on to 62 grains of Varget for increased velocity. As will be mentioned below, there are other ways to add that velocity.

My tests also revealed three interesting things that I had never observed previously because I generally load at home. First, standard deviations tightened when I trimmed the cases, which I did after the fifth or sixth firing, when I observed the extreme spread and standard deviation go way up. Secondly, they tightened further when I cleaned the primer pockets before re-priming. Lastly, perhaps most surprisingly I observed that, when I lubed the case mouth very slightly to ease passage of the expander button, the velocity dropped nearly 25fps and extreme spreads and standard deviations went up significantly.

I conclude from this that cases should be trimmed prior to their "for real" loading, their primer pockets should be cleaned before being re-primed, and bullet should be "crimped" in insure proper neck tension. At these velocities with their attendant pressures the cases are good for well over eight re-loadings. I'd suggest, if shooting high intensity loads, sectioning a case after 8-10 reloads, and then section a case from that lot every second reloading until signs of case separation are observed. At that point, trash the entire lot and start over.

The recoil from the 286 Partition right at 2400fps is unpleasant from the bench, but it would be quite tolerable in hunting situations. However, as mentioned in the discussion of the 9.3x62 as a dangerous game rifle, velocity isn't everything. The next task is to find a comfortable load for the 286grain Woodleigh solid (and soft point) and determine their trajectory. This is for a reliable, low recoil, dangerous game load. Ku-dude

PS: ppod commented about using only one load, the Partition, as a KISS issue. This is a valid point; however, because of the perceived need to have a "long range" antelope load, I will carry the 250BT on the trip. The 286 Partition and 286 Woodleigh soft point essentially do the same thing, kill large and dangerous animals. I would want to use solids if following up on Bufalo, but any of the 286 loads would be sufficient for everything else. The good news is that, when zeroed from max point blank range, they all have the same curve out to 200 yards. Life is really good, and the 9.3 is such a wonderful cartridge! k-d

Ku-dude,
I like very much these topics on 9.3x62, and I have only a consideration about them, they should be only one. This morning, here in Italy of course, I visited the forum and the second topic was still highlighted, four new answers were arrived.

Except this consideration, I benevolently envy you because you can spend so much (powder, bullets,etc.etc. money in short and moreover time) in conducing these tests.