Gunwerks G7 BR2 Rangefinder Review

[COBrad]

I was down in Utah shooting prairie dogs a couple weeks ago. This was an interesting test of the G7, and it did not fare well this time.
I have used it extensively ranging marmots out to 1400 yards, and it worked quite well, but this was all in steep mountains above timberline where the hillsides formed pretty vertical surfaces to range against.
Out in the flats of the high desert, the unit had a hard time getting accurate ranges at longish distances, 600 yards and beyond, unless the target was on even a slight hill. I even had a hard time ranging antelope around 950 yards, but it seems part of the difficulty was lighting.
All in all I am still very impressed with this unit, but I will have to gain more experience with it in this setting to figure out how to get accurate ranges every time.

 

[Greyfox]

I was down in Utah shooting prairie dogs a couple weeks ago. This was an interesting test of the G7, and it did not fare well this time.
I have used it extensively ranging marmots out to 1400 yards, and it worked quite well, but this was all in steep mountains above timberline where the hillsides formed pretty vertical surfaces to range against.
Out in the flats of the high desert, the unit had a hard time getting accurate ranges at longish distances, 600 yards and beyond, unless the target was on even a slight hill. I even had a hard time ranging antelope around 950 yards, but it seems part of the difficulty was lighting.
All in all I am still very impressed with this unit, but I will have to gain more experience with it in this setting to figure out how to get accurate ranges every time.

I had similiar difficulty until I figured out which range mode to use for each circumstance. It's very fast and accurate ith some practice and can get a range when other RF's cannot.

 

[Jerry Cunningham]

The great thing about this forum is that you can glean so much from other shooters. Here is something to think about. I had access to a military rangefinder for a couple of years. It was not eyesafe but it would range nearly anything. When you hit the button it was like the hammer of God. It gave the range immediately. However, it was so expensive that I hated to even handle it. One thing I learned was that the aiming square or circle typically is the width of the projected beam at the target location. I also own a Leica 1200 and a Swarovski Guide. I strongly suspect the aiming square or circle is the beam width with those units as well. However, I don't know that for sure.
I have heard that the eyesafe feature has more to do with the wave length of the pulse and not anything to do with the strength of the laser itself. I read that somewhat on a newer rangefinder for the military. Therefore, I really don't understand why the G7 BR2 can't range further. That said the G7 sounds like a good unit because it gives the firing solution right away. Time is of the essence when you have to make a shot.
I would also like to mention that the Lieca and the Swaro will fill many hunters needs. For example, the Lieca 1200 ranged a coyote at 900 yards+ and under very good conditions I have ranged 1250+ many times the Swaro. The truth of the matter is that a 800 yard shot is still a heck of a shot. Having the latest and greatest is not absolutely necessary to have quality long range hunts. New products often have new unknown bugs. Often the cost of being on the cutting edge is the price of being an unpaid bug finder.I personally feel that a rangefinder will reliably range about half of it rated range. That means the Lieca 1200 is typically a 600 yard product in the field under nearly all conditions. If a buyer applies the "half rule" on rangefinders he/she will have few surprises.
The last suggestion is that rangefinders can do no better than the user holds them. With using a tripod the user can typically extend their ranging ability by about 20% to 30%. A rangefinder is just like a rifle. If you don't hold dead on you will "miss." The number the user gets may not be the target. Hopefully this will add to the group thoughts.

 

[COBrad]

Jerry C, IME I find your comments to be accurate, though I have not had opportunity to use a military grade LRF.
The primary reason I chose the G7 over the Vectronix PLRF05 was the ballistic software and fast solutions built into the G7. I have not been disappointed. Even shooting the lowly marmots were frequently gone by time I had ranged, consulted my drop chart, calculated come-ups, and dialed them in.
I am heading down into Utah again tomorrow and will do some more testing to learn how to get accurate ranges from the unit in that topography.

 

[Jerry Cunningham]

CB
You are so right. Getting the firing solution is where it is at. Getting the right dope fast enough can make or break your season! I will be watching to hear about your experience with the G7. Best of luck!
Sincerely,
Jerry C

 

[COBrad]

I was able to test the unit a little more yesterday on a prairie dog on the flat high desert above Moab Utah. The only one I shot at was somewhere between 725 and 775 yards. I could not be sure. I ranged with the tiny target high in the aiming square, as well as low. I took multiple ranges, and it appeared to be 725, which called for +13.5 MOA. I fired and found I was a couple MOA low. After several shots I ended up at +16 MOA, which my data sheet says should be 775 yards.
I walked out to the mound he had been sitting on, and ranged back to my car. That range was an even 750 yards.
I am going to do more field testing of the rifle on targets before I test the rangefinder any further in that setting. I know from the other two rifles I have entered into the rangefinder that I had to do some very careful testing before I got it dialed in.
I am happy to say that, for those two rifles, it is dialed. I was ranging and shooting at marmots out to 1380 yards earlier this fall with my LR varmint rifle, and shooting my light weight elk rifle out at 842 yards yesterday. In both cases ranges and corrections were right on.
Once I am certain I have the rangefinder and rifle in sync, I'll try again.

 

[Jerry Cunningham]

COBrad

Please let us know your continuing results. I have found that praire dogs and antelope are the very hardest test for a rangefinder. Keep us abreast as many of us are looking for field information. That of course applies to anyone who is using the G7.

Thanks again,
Jerry C

 

[Greyfox]

This season I have spent more then 2 weeks of time in stand and had the opportunity to range well over 100 animals. I went through a couple of batteries! Also was able to get comparison readings using Leica Geovids and Swarovski binos. Some observations:
The accuracy of the G7 compared to the other finders out as far as 1300 yards was many times within 1 yard, many times identical to the other finders.
The target animal, especially out past 1000 yards, the animal has to be exactly in the middle of the ranging square and a rest used. Poor or no readings were almost always caused by lack of steadiness. I was able to get readings on small whitetail does and antelope out to 1400 yards on flat, hilly, and brushy foreground and background terrain. Knowing how to use the near/far ranging capability makes a BIG difference with difficult targets. With practice you can determine range differences of the interferences and pinpoint your animal.When in doubt, get replicate readings. If they are the same or within a yard or two, it's usually a good reading. You will get erroneous readings with glare or ranging into a sunset.
The ballistic program matches my Shooter program and rifle set-up exactly.

 

[COBrad]

Greyfox, thanks for sharing your experiences. I have been ranging in the different modes, trying to learn how to best use this unit. When I have been able to get multiple readings within that yard or two, I have had good success. I'll keep working on it until I get it figured out. I am still not entirely satisfied my data for the 22-250 is accurate enough yet to be reliable. I need to do some more field shooting to verify my actual drops.
I was thinking about that Utah PD this morning, wishing I had tried a few shots with the 270 WSM I had with. I have done all the work with that rifle and the solutions I am getting from the G7 for it have been spot on. On that same trip last week I ranged a paper target at 842 yards, then placed a shot from the 270 1.5" above center of bull. I tried again and placed another 1st round cool barrel shot right on for horizontal and 1/2 MOA left of center.
The G7 has worked better than I really expected with the two rifles I have really tuned the input data for.

 

[Greyfox]

Greyfox, thanks for sharing your experiences. I have been ranging in the different modes, trying to learn how to best use this unit. When I have been able to get multiple readings within that yard or two, I have had good success. I'll keep working on it until I get it figured out. I am still not entirely satisfied my data for the 22-250 is accurate enough yet to be reliable. I need to do some more field shooting to verify my actual drops.
I was thinking about that Utah PD this morning, wishing I had tried a few shots with the 270 WSM I had with. I have done all the work with that rifle and the solutions I am getting from the G7 for it have been spot on. On that same trip last week I ranged a paper target at 842 yards, then placed a shot from the 270 1.5" above center of bull. I tried again and placed another 1st round cool barrel shot right on for horizontal and 1/2 MOA left of center.
The G7 has worked better than I really expected with the two rifles I have really tuned the input data for.

My situation with the G7 was quite easy. I had already established my ballistic data/drops a couple of years ago using Ballitic FTE for my 6.5x284. Both the G7 and FTE use JBM software so the outputs were identicle. All I really did to confirm this was to take readings at actual ranges and compare the drops which were dead on. Also tested the angle and atomospheric outputs as well which were also the same for both devices. My final test was to use a 1000ft/50 degree temp yardage turret when I went to Wyoming. Using this turret with the G7, at 4700 feet/33 degrees at a 12 degree angle I used the adjusted yardage output of 1004 yards to hit a few inches right of a softball sized rock. I didnt correct for a spin drift of 6 inches. Even more impressive was when I had a group of does at 700 yards. There were two that were partially in line with each other. Using the near/ far modes I could distinguish the difference they were apart by 12 yards. Set up for the shot is so fast with this thing I actually feel like I'm cheating!

 

[AaronSkipDavidson]

I was able to test the unit a little more yesterday on a prairie dog on the flat high desert above Moab Utah. The only one I shot at was somewhere between 725 and 775 yards. I could not be sure. I ranged with the tiny target high in the aiming square, as well as low. I took multiple ranges, and it appeared to be 725, which called for +13.5 MOA. I fired and found I was a couple MOA low. After several shots I ended up at +16 MOA, which my data sheet says should be 775 yards.
I walked out to the mound he had been sitting on, and ranged back to my car. That range was an even 750 yards.
I am going to do more field testing of the rifle on targets before I test the rangefinder any further in that setting. I know from the other two rifles I have entered into the rangefinder that I had to do some very careful testing before I got it dialed in.
I am happy to say that, for those two rifles, it is dialed. I was ranging and shooting at marmots out to 1380 yards earlier this fall with my LR varmint rifle, and shooting my light weight elk rifle out at 842 yards yesterday. In both cases ranges and corrections were right on.
Once I am certain I have the rangefinder and rifle in sync, I'll try again.

Nearest mode is the ticket for ranging those prairie dogs and antelope on the flats. Most lasers are 905 nm wavelength, this is just outside the visible light spectrum, but not enough that our eyes can't be damaged. The eyesafe requirement actually limits the power output. Military lasers are generally 1550 nm, which is outside the visible spectrum, and you can pump as much power as you want. Big different in cost of the laser diode!

You can use the G7 Ballistic Calculator on our site or here at Lens site to calculate exactly the same calculation that the rangefinder will calculate (both use the G7 Ballistic Engine). If it doesn't match, use the Trajectory Validation feature to correct your muzzle velocity and use the corrected Ballistic Profile (BC and MV) in the BR2. The correction will match.

 

[COBrad]

Thanks for your input Aaron. I tried the far mode, but did not try the near.
After careful field testing at both near and extended ranges, I used the validation feature with the two other rifles I have programed into the rangefinder. In both cases I get solutions that are accurate beyond my expectations.
I need to do more of that kind of testing with the 22-250 to be certain my input data is correct.
Once I am confident my data is right, I'll head back down and work with it again.
Sad part is the barrel is about toast in that rifle. I bought another thousand JLK 52 gr. Low Drag bullets for this winters' shooting, and expect to rebarrel next spring, when they are gone.
I guess I'll have reason to do a lot of shooting again to get data for a new barrel.
It's tough, but someone's gotta do it.

 

[COBrad]

Ah HA!,
I did some more testing with the 22-250 over the weekend. I discovered my input data was flawed.
I shot groups at 100, 289, and 576 yards, then spent some time on the G7 web site changing things on the Ballistic Calculator until it all fit with the new data.
My velocity was off by 127 fps according to the Trajectory Validation feature. I wonder if the amount of throat erosion since I last collected field data could contribute to this.
The 52 gr. JLK low drag bullets are represented as having a BC of .309. In previous testing I concluded it was .244. On G7 I changed it to .242 and my field results matched precisely what the software predicted.

This barrel may be about shot out, but it is still shooting; .178 three shot at 100, and just a hair less than half MOA 5-shot groups at the longer ranges.

 

[alarsene]

If i could get data like that with my 22-250 i'd post to the forum as well.
I'd say you have it together very well with a bit of erosion or a head wind?