Shawn Carlock
Sponsor
Cutting Edge Bullets Test
I talked with Dan Smitchko at Cutting Edge Bullets (CEB) about a project we were looking at for extreme distance shooting and agreed to send some test samples for us to try. Dan had sent some early samples to us years ago and said that these were generations ahead of the ones I had tried prior with mixed results. I was excited to give them a run again as I had been hearing good things form a couple of people whose opinion I respect. I was looking for a couple of things, we were searching for a 375 bullet for an upcoming project that was high in BC, heavy for caliber, match quality, suitable for hunting and above all supremely accurate. This as you know is a pretty tall order.
I received bullets from CEB in the following configurations:
· MTH 338 265 MAX Single Feed 1-10 twist BC .800
· MTH 338 275 MAX Single Feed 1-9.5 twist BC .820
· LZR 338 275 MAX Single Feed 1-9.5 twist BC .773
· MTAC 338 277 Mag Feed 1-9.5 twist BC .825
First test will be the MTH 338 275 MAX, I will test this in the shop LRKM chambered in 338 Terminator (Gen 1 short chamber). As I have not worked with a solid bore rider design much and have seen several variations on this the first course of action was to measure and spec the bullet itself. With the measurements out of the way I checked the oal to the "touch point" of the bullet in the chamber. My initial concerns were that the +P portion of the throat might not support the bullet like it would want for killer accuracy.
OAL Base to Tip: 4.055" I was advised by Dan to start testing with the "sealing band" .025" off the touch point as a minimum.
Armed with this information I started looking in Quickload for a good starting load. Using the following specs:
· OAL 4.030" with MTH 338 275 MAX
· Primer: CCI 250
· Case: 338 Terminator – Formed / Fired 2x, Hornady Brass
· 32" 1-9.3 twist barrel
It appeared after some debate on my part that RL 33 was the top velocity powder at just over 3220 fps and a max load of 118 gr. This was using 103% of case capacity so a drop tube might be in order. This load is probably close to max, I shoot the 300 gr Berger in this rifle normally and both RL 33 and VV N570 regularly achieve 3100 fps with these powders. Like I said, I'm just looking for a good solid place to start. Test loads as follows:
Charge Velocity Notes
112.0 gr 3172 fps
113.0 gr 3198 fps
114.0 gr 3227 fps
115.0 gr 3250 fps faint ejector mark
116.0 gr 3289 fps ejector mark, bolt lift and extraction tough, no tap
Also powder density pushed OAL out .006"
I am going to start load development at 114.0 gr of RL 33 and go from there. Even with different powder charges seemed like it wanted to shoot well. Next load development step:
OAL Group ES Notes
4.030" 2 + 1 11 fps Bullet runout on 2 were perfect <.001" the 3rd
was .006" out. They said bullet runout was critical
4.025" 2+1 6 fps 2 in a hole 1 touching, nice load, velocity
average 3227 fps
Loaded up some test rounds at:
4.025" OAL, CCI 250, 114.0gr - RL 33, Hornady Case trimmed to 2.830". I will test these for accuracy and long range BC validation at 784, 965 and 1880 yards. I expect good things here.
Reloading notes: Bullet runout is critical as instructed. I had to use a bushing .002" smaller than the loaded case where the bullet was seated (sealing band was not in the neck, but setting right at it). If you normally run a .366" bushing you will need to drop to a .364" bushing as the rear portion of the bullet is smaller than a conventional bullet. With this neck tension you can faintly feel the machine marks on the bullet passing the neck.
Expansion testing impact speeds of 3225 fps and 1600 fps to simulate close range impact and 1 mile impact. Note reduced load of H50BMG to achieve muzzle velocity of 1650 fps is 65.0 gr.
12-06-16
2987'
26.8 baro
51%
28 degrees
I ran the advertised BC of .820 and our chronographed velocity of 3228 fps at distances of 784 and 986 yards. BC appear to be spot on. Conditions didn't allow for longer range testing, the wind over terrain features was too unstable to test with. The accuracy in the conditions we had to work with looked really promising.
12-08-16
Loaded some long range test loads:
275 gr. MTH / MAX
4.025" OAL
CCI 250
114.0gr - RL 33
Hornady Case trimmed to 2.830"
Average Velocity: 3228 fps
