Gunsite XLR class- system calibration

[CoryT]

After twp XLR classes here this month, I can tell you that the combination of the Labradar and Shot Marker targets are the absolute heat for calibrating the ballistic system. We currently use the following system to get valid configurations for your ballistic computer.

1 Establish a solid 100 yard zero
2 Determine 300 yard actual drop, Labradar for velocity
3 Calibrate rifle scope using bore sight laser
4 Enter base data into computer, confirm 300 yard solution matches drop data +/- .1 mil or .5 MOA
5 Shoot at 500 yards on paper to confirm settings while using Labradar for velocity
6 Move to 500 yard Shot Marker target, getting shot position with muzzle and target velocity reading, correct elevation as required and record
7 Move to 1000 yard target, getting muzzle/target velocity and elevation setting, correct elevation as required and record
8 1436 yard steel target test, correct elevation as required and record
9 In classroom, run BC computation using 500 and 1000 yard velocity pairs to get true average BC
10 Update computer and compare output to actual recorded elevation settings
11 Shoot steel on the 1500/2000 meter ranges, alternating between near/far targets and checking impact against waterline/multi plate targets

This is proving to be VERY accurate and requires a minimum of ammo. 40 to 50 rounds should get a solid BC and the 1500/2000 m ranges should just be confirmation and minor tweaks to velocity/DK/DC/BC depending on the software used.

The Shot Marker targets are huge time savers and also provide a velocity at the target which has proved to be VERY accurate if the frame is solid and well made. They are well worth the investment, but make sure you take the time to build good frames. I made mine from Aluminum square tubing so they are rigid and lightweight. I use strapping tape to suspend an aiming point so wind does not vibrate the frame.

The Lab Radar NEEDS the airgun microphone for reliable triggering with suppressors. I use the Android or iPhone app to run the unit from behind the line. The unit also needs a solid base, I made one from 1/2" marine plywood and 1x2's for feet, using a Manfrotto ball head to align the unit and a 10lb weight on the base to eliminate movement. This has resulted in very reliable readings. A USB battery pack runs the unit all day

We are contemplating getting one of the new Oehler System 89's, but I'm not sure it will improve on the current system.

Cory

 

[timintx]

Cory, The Oehler system will help immensely. The Oehler system is great for studying bullet stability and down range velocity and BC, not to mention the velocity reads will be more accurate at least from my testing. I was having trouble truing at 2650 and once the Oehler numbers were input to my program it matched to the click. This is not meant to be a rag on labradar but with radar in general there are a lot of variables that can and will affect your velocity reads and on the Oehler not so much. Good luck to you sir.

 

[CoryT]

I was not aware they were delivering yet, I'm on the order list and last I heard they are still 30-60 days out. A System 88 would l d be great, but I can't afford that, stuff like this comes out of my pocket, Gunsite won't buy it.

 

[overspin67]

Cory, would it be possible to know the approx. price for an Oheler System 89 BC? Thanks...

 

[CoryT]

My quote is for 2495, less the required Windows laptop. That would give you one target.

 

[northern50]

Good stuff. I'll have to look into the shot marker system. I've been using the Oheler 88 b.c. number for my 416 in FFS. Calibrated scope, correct zero and velocity from labradar has been spot on at the spearpoint matches. Elevation check at two miles was perfect with a 3 minute right impact of target due to wind, can't be mad at that. Having good data to calibrate and work B.C. Numbers is money in the bank for getting things done efficiently.

 

[CoryT]

The 88 is the heat for sure, but SPENDY does not begin to cover it. I balk at spending six figures on stuff for classes. Now if I turn up a winning lottery ticket, that could change. Of course I never buy tickets, so it's a bit less likely for me to win, but just a bit

 

[northern50]

Haha, you and I are in the same boat for the lottery then. Thankfully our bullet maker has the 88 and we get to utilize the data. Prior to this all my data is collected the old fashioned way, on paper. All other operations are equal to yours. The shot marker system would be real nice to correlate velocity to a single shot vs, shoot five then run down and measure the average, etc. gotta love time savings.

 

[CoryT]

Yeah, the Shot Marker is instant feedback, shot location and downrange velocity. If you use the Lab Radar at the same time, you can correlate velocities to POI, have group size and offset to POA and it's all instantly available and saved for further analysis. You can use the target at any range the bullet is still supersonic, just make the frame an appropriate size and make it STIFF, a wobbly frame will not provide good data.