Home Forums Hunting & Shooting Ask The Gunwriters Measuring BC.

It seems as if the ability to measure TOF/drag/BC is about to be within reach of more shooters.

Dr. Oehler sent me a document yesterday that describes the Oehler System '89. The '89 was born from lessons learned with the '88.

I have a System '88. I've used it to measure time of flight (TOF) and BC on a number of tests. I've had a lot of fun and learned a lot of things with my '88. I believe in the technology.

I was present when both an '88 and a Weibel radar were operated for a 10 shot test at just about 1 mile. The two systems agreed within 1 fps on velocity and to the third decimal place on BC. The operator of the radar later said he thinks the placement of one of his instruments probably accounted for the 1fps variance (I guess he also believed the two machines were in agreement).

In my opinion, the development of this technology may be as important to long and extremely long range shooting as the chronograph has proven to be. Shooters will have the ability to not only choose loads with the most consistent velocity, they can choose loads with the most consistent drag (BC). For what it is worth, one of the highest BC .30 caliber bullets I've ever tested had a significant spread in BC over 10 shots. In other words: Yeah, the average looked good but the shot to shot variance would render hits as attributable to nothing but luck.

I don't know how to post the .pdf here. If someone will tell me how to do it, I'll do so. Alternately, I can email it to you if you know how.

I know Dr. Oehler frequents these forums so I'd like to tip my hat to my friend and say "Thanks, Ken".

Is this it?
https://oehler-research.com/wp-content/uploads/2017/12/System-89-Prelim.pdf

Tyrone, that is an older document, from the concept days. The one I got from him, yesterday, is more current. I'm still trying to figure out how to post it.

If you email it to me, I will post it here. Sending my email address on PM.
Chris.

Emailed to you, Chris. Thanks!

Thank you Chris & Mr Boone :

I haven’t had time to digest all of that, but find it VERY interesting. One point in particular - I’ve attempted to point out and was hoorahed - is brought out here. “Time of Flight” has bearing on more than BC.

One reason I’m NOT interested in Less Velocity (slow bullets & SLOW cartridges) is longer Time of Flight. It IS real and can have negative consequences. Maybe, Hopefully, this article will turn on a light for ‘some’ at least.

Also I promise to NOT derail this thread by getting involved in an argument/s over this specific point. I will not take the bait.

THANKS to both of you & Dr Ken.


BTW I’m still using my O 33 that I bought in 1981. It provides all the data I need, not being involved in really long range hunting.

Jerry

This is an amazing advancement for the little guys doing long range work needing precise BC's. FWIW, there's tell that the (non-gubmint) folk doing serious work of this type have dropped over 100K on set-ups to do similar.

Funny aside; almost 20 years ago, LarryB was telling me about his experience in Texas capturing velocities and TOF at 1000 yards using TWO M43 PBL's (with acoustic targets) and a whole 'lotta Cat5 cable and an amplifier. Seems that one of the limiting factors was the ground squirrel's and mice' appetite for the cable insulation. My recollection was that Dr. O was on site to lend his technical expertise (but apparently his expertise did not extend into rodents). I'm going to guess that the M89 is the grandchild of that earlier effort and I am amazed that all of this can now be setup and operated by a single person with a laptop.

*

I just heard the price of the System '89 is $2,485.00

When Dr. Oehler told me he thought he could price it "About like a good scope", I had visions of a Schmidt Bender, or similar.

This is significantly more affordable than I expected.

These are exciting times.

Buford,

Thanks again for your posts--and Ken, who just keeps truckin'.

That's a bargain for those who want to know, rather than guess!

Thanks for sharing. It's always good to expand one's horizons, even if one is like me and has zero interest in long range shooting/hunting nor the places to do it.

What distance is the BC measured over with the new 89?

Inasmuch as the '89 uses the same sensors as the '88, I believe it would have the same distance capabilities. The radio link between controllers may actually be more powerful.

I have used (or been present during the use of) the System '88 at distances as short as ~100 yards/meters and as long as two (2) miles.

The 2-mile target was a plywood wall 12' wide and 8' tall. The '88 got data every time the target was hit.

MD - Stop by the Oehler Research Booth next week. I'd enjoy saying hello. I've been spending the last few SHOT Shows with Dr. Oehler (call it "getting some Ken time").

These are exciting times for ELR shooting.

Unfortunately, I'm not going to be at SHOT. Otherwise I'd definitely do that....