Others FX True Ballistic Chronograph

[Alan]

The TBC has been shipping for about two weeks. I received my early last week. It is everything FX says it is, but unfortunately not all of the features have been activated. One example is the data stream. It appears that all of the data presented on the screen (preset distance velocities, BC etc.) are send via BlueTooth, but the current smartphone app doesn't suppose the data. The small chronograph velocity readout can't be used either. Not that you need it, but it should in my opinion.

One good thing, the RA4 ballistic profile (22LR) is included (can be downloaded if not), but ever that falls short past about 100 yards. Hopefully soon, FX will include more accurate profiles for both pellets and slugs.

Alan

 

[jnjhess]

Nice piece of equipment, wouldn't mind to have one. But is to rich for me, so i will do with the FX Pocket crone what i own right now, it does so far everything i need, but would be nice to have all that bells and whistles avail.

 

[rsterne]

I certainly hope that FX unlock all the data they must record with every shot so that those that want to can do a deep dive into it.... It would be an immense help if they recorded it onto an SD card like the LabRadar does, so that transferring it to your home computer would be a breeze.... It is obvious that the G1 profile most are using is not suitable for airgun slugs, if you measure the BC of a slug at 800 fps and then check it at 1000 fps, the G1 profile calculates a huge difference.... Since the BC should be constant at every velocity if the drag profile matches your slug, and you would get big errors in trajectory if you use the wrong BC(G1).... I am delighted to hear that FX have now included the RA4 drag profile, as that is a vast improvement over the G1 for our slugs.... However, given the data that these ballistics radars gather, an even better profile can be developed....

Bob

 

[Alan]

I am confident that FX will indeed "fix" the shortcomings. When is the only question.

I can capture the BlueTooth data stream, and it does appear to be somewhat more robust than just the velocity. I suspect the shortcoming is the app, not the TBC. That said, they do need to pay attention to the more-astute airgun hobbyists who are capable of developing a ballistic profile to properly fit both slugs and pellets. And... make sure these new profiles can be added to the TBC.

 

[Alan]

Once you figure out how to launch the correct page of the FX smartphone app, you can look at most of the "needed" ballistic data. In other words, you can use it to set the hold over (under too). It is certainly closer to reality than a static BC, but as predicted, the RA4 profile is not ideal. This said, setting the distances at 100, 150, 200, and 250, the POI is is closer to ideal. That is, within a 1.5 inch kill zone (Point Blank Range as it were).

 

[N28763]

I am a benchrest guy. When I see someone using the device on the line in competition and actually improving their score real time @ 100 yards I'll be less skeptical for bench purposes. I theory, it would allow you to adjust your speed to the very best for conditions. This is great for our "almost no rules USA Extreme competitions" but it will never fly in worlds... well for now I'd LOVE to see someone shooting in real time (video) and adjusting using the FX to current conditions. That would be a GREAT video and make me consider it...

 

[CTAirgunner]

Is it really worth it over the labradar as well? I have been wanting to ditch my pocket chrono for a better chronograph , I use the pocket chrono to tune for consistency and accuracy... as simple as possible and leave it there. I just know the pocket chrono is not the most accurate especially when conditions/position of the chrono could change day to day.

 

[Alan]

I not sure adjusting the velocity is as important as adjusting the hold over-under as the case may be. Even as it sits (sans upgrade to a better app), is does show the basic BC, and as well know, that figure is dependent on the ambient conditions.

Playing with the TBC set at the RA4 profile (and messing with the current app) to figure the POA, works very well out to about 100 yards or so. If you're calculating the POI as a point blank range of 1.5 inches, you're within the PBR out to 125 yards. This on a target range, not afield.

 

[Centercut]

I certainly hope that FX unlock all the data they must record with every shot so that those that want to can do a deep dive into it.... It would be an immense help if they recorded it onto an SD card like the LabRadar does, so that transferring it to your home computer would be a breeze.... It is obvious that the G1 profile most are using is not suitable for airgun slugs, if you measure the BC of a slug at 800 fps and then check it at 1000 fps, the G1 profile calculates a huge difference.... Since the BC should be constant at every velocity if the drag profile matches your slug, and you would get big errors in trajectory if you use the wrong BC(G1).... I am delighted to hear that FX have now included the RA4 drag profile, as that is a vast improvement over the G1 for our slugs.... However, given the data that these ballistics radars gather, an even better profile can be developed....

Bob

Bob, what is this new G5 profile that I've seen pop up in Chairgun Elite+? It says it's for blunt nosed boat tail projectiles, but perhaps it could fit airgun slugs, especially those like the Altaros Smooth ATP? Thanks,
Mike

 

[rsterne]

It is not new, it has been around for years.... It is "blunt" compared to the G7, as that one has a spire point....

The G5 model has a tangent ogive and boattail, making it useful for bullets that share that basic shape. However, it is so close to G7 that it is almost never used.

It is not very similar to our slugs in shape.... Here is a chart showing various Drag Models....

So far, the RA4 profile is the best match for out airgun slugs.... It is based on the .22LR bullet....

Although Ondrej uses the G1 profile in his advertising (because the numbers look great), he actually uses the G7 profile when doing his long range shooting with the Altaros slugs.... Interestingly, the RA4 profile is much like using the G7 Cd times about 1.5.... in other words the shape is similar but the BC numbers are more like what we are used to seeing when using the RA4 instead of the G7....

Bob