Had a lot of $$$ in molds for the 30cal's and thought why not spend a little more and buy a good match grade bbl for those molds. Ended up ordering a shilen 30" bbl with a .340 match chamber. Did some initial testing and saw the good, the bad the ugly. The good was the bbl showed promise with hv pc'd bullets. The bad & the ugly was me and my lack of effort in the rifle's setup and the range equipment used.
All testing is @100yds.
This was the 1st outing I put any 10-shot groups on paper.
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Did a 2nd outing and saw horizontal stringing.
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In the 1st outing that 35gr of h3335/160gr lee tl pc'd group actually looked pretty good except for the 2 fliers. Was starting to test rl19 in the 2nd outing with 186gr/180gr bullets (2350fps load/left). Figured that was a good place to start. So I finished bedding the bbl, changed to high rings. Changed the rear bag I was using & changed targets. The other thing I did was open the box on a new 308w that I bought 2 years ago & brought it to the range to test for function. It's always good to have 2 rifles at the range of the same caliber. Any issues with ammo you can check it with a 2nd rifle. Or pick up on mechanical issues like inconsistent ignition, resetting the torques (receiver bolts),etc.
Finely got a little time and a break in the weather and hit the range and got both rifles sighted in and did 2 different test loads with the 30" bbl'd 308w. I started out with the 35gr of h335/lee 160gr tl pc'd bullet and shot a 10-shot group. Saw vertical string in the 1st group (left target) so I reset the torques on the hold down bolts and shot the 2nd group. Too tight/too much torque on your action screw will cause vertical stringing, too little will cause horizontal stringing. You want round groups & 10-shot groups will clearly show if they are round, vertical, horizontal, etc. The 2nd group can in @ just under 2" (2 1/8" outside to outside) and the vertical stringing was gone.
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The initial rl-19 test load (2350fps/44gr) didn't do well. So I bumped the load up to 46gr trying to push the velocity into the +/- 2500fps range. I loaded up 10 rounds of each bullet cast from a cramer 2 cavity mold. The mold casts a 186gr sp bullet and a hp of that same bullet in the other cavity. It a cramer #43 that is similar to the lyman 311334. The 46gr load did surprisingly well. Looks like I'll be doing more testing refining.
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That hp bullet/10-shot group had 9 shots in a 1 3/8" group outside to outside and 1 flier that opened the group up to 2 1/8" outside to outside. Don't know when the flier happened because I set the rifle up to test the rifles setup/myself, not the loads. To do this the bullets impact should be out of view in the scope. The shooter only sees the aiming target and works on trigger control, scope alignment, scope/target alignment, consistent hold. The shooter never sees the groups/bullet impact. I set the rifle up for 15moa and shot those 4 groups above. What the rl-19 targets looked like. I was aiming at the small red centered targets (bottom) and the bullets with hitting 15moa (15 inches) higher out of the field of the scope.
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It's a start, got rid of the horizontal stringing & just shot 4 10-shot groups with 2 loads & 3 different pc'd bullets that averaged under 2"'s and had 2500fps+ average. Changed the rings from medium to high & didn't like the high rings I put on the rifle so I ordered a set of burris with the offset insets. Need to refine the rear bag a little. Just need to keep dialing everything in to be able to push 14 different pc'd bullets to their limits. I'm hoping to get the 180gr+ pc'd bullets in the 2600fps+ range and the 160gr- pc'd bullets in the 2900fps range. The 10-shot groups need to be cut down to the 1 1/2" range.
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