Author Topic: New Play Toy  (Read 556 times)

Alan

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New Play Toy
« on: March 29, 2018, 05:03:20 PM »
I bought the laser pointer and scope mounted Picatinny rail adapter from Amazon Prime for $19.95, and $9.95 respectively. Making sure everything was proper aligned took about 30 minutes, using three small levels, including one which clamps on the Picatinny mount. But it isn’t just the parts which tell the story.

The laser pointer is green, rather than the traditional red, and for the price I paid, it isn’t bad. The adjustments aren’t all that great, but it is workable. It uses a single rechargeable CR123 which costs about $1.25 on Amazon. They last for about 20 hours of off-on use. By the way, for a few dollars more, you can get the charger with it, but I already had one.

Now pay attention to the fact the laser is green (532 nm)! They say it can be seen for 300 meters, assumingly at night. Well… In daylight, I can see the green dot past 100 yards while looking through the scope. At night, the dot can be seen well past 500 yards. But enough about the hardware.

The centerline of the laser is 2.375 above the scope’s centerline, and the scope’s centerline is 2 inches above the bore centerline. I should mention at this point, that the gun shoots 25.4 grain pellets at ≈884 FPS.

Getting to the meat of the deal, I had to relearn some high school math (drat!), and get out my Casio calculator! But it turns out that sighting the scope and laser at ≈60 yards, places the laser beam very close to the mil dot distances. At least close enough to have a ± 1 inch kill zone from 10 yards out to about 125 yards, which is beyond what I normally shoot.

The graph isn’t all that great or to scale, but I think you can get the idea of what is occurring. Rather than hold over using the mil dots, I just put the laser dead on, and pull the trigger! It worked good enough today, to take 4 pigeons from 40 to 65 yards!



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Alan

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steveoh

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Re: New Play Toy
« Reply #1 on: March 30, 2018, 10:05:28 AM »
This is very interesting Alan. I've often thought of lasers, but never did actually buy a set up. 

Very clear graphic too.

Pigeons didn't notice the laser?
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rsterne

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Re: New Play Toy
« Reply #2 on: March 30, 2018, 11:09:32 AM »
I tried a laser setup, but instead of using it to aim, I used it in conjunction with the scope for a rangefinder.... I mounted the laser on the bottom of one of my reversed tank blocks, where I have a Picatinny rail to mount a BiPod.... That placed it 4.0" below the boreline, so about 5.5" below the scope.... I aimed it upwards so that it intersected the 2nd MilDot  above the crosshairs at 100 yards.... I then made a chart and table for where the laser dot was, relative to the upper MilDots, so you can use that to determine the range.... Then you use a table to get your holdover as normal, except you have a pretty good idea what the range is....



The lines on the chart are 1/2 MilDot apart.... so halfway between the dots on the reticle is 0.25 MilDots on the table below....



The large distance between the laser and scope increases the convergence angle, so it lets you get a better estimate of the range.... I tried it out, and the green laser I had was visible in daylight out to about 100 yards if it was on a dark, even target, but the cheap laser I was using had a relatively wide spot at that distance.... However, the idea worked well within about 70 yards or so....

Bob
« Last Edit: March 30, 2018, 11:13:28 AM by rsterne »
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Alan

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Re: New Play Toy
« Reply #3 on: March 30, 2018, 04:47:06 PM »
I didn't mention the range finding (estimate) ability, and probably should have. Thanks for reminding me!

The way it is, isn't perfect. I tried to use a rail extender on the bottom rail where my bipod is usually attached, but that was too, shall I say, flimsy.

The laser I bought isn't anything to write home about, but it is 5 mW so 100 yards on a dove isn't out of the question if there isn't too much sun light. I have a similar one on my 397, but I remove the scope from the rail, and install the laser for shooting in the hay barns. In that case, I sighted it in for 15 feet, as the roof is about 20 feet. It doesn't matter in that case how big the laser dot is, you just put the dot on the pigeon, and pull the trigger. Heck, you don't even have to shoulder the gun!

By the way, I like your graph better than mine! I could have used Chairgun, but I'm on OS High Sierra, and the requisite Java app won't run.And speaking of that, I didn't get a warm feeling from Chairgun when I brought that fact to their attention.

Thanks again Bob; you're the man!
  • Roswell, New Mexico
Alan

I have an Omega compressor. If you're a fellow Guild member, and you pass through Roswell, NM, I'll fill your portable tank as a courtesy.

Monkeydad1969

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Re: New Play Toy
« Reply #4 on: April 09, 2018, 09:42:07 AM »
Cool stuff... 8)
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Alan

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Re: New Play Toy
« Reply #5 on: April 09, 2018, 11:26:19 AM »
While we're on this subject....

Using two vertically-placed and properly mounted lasers (one red, one green), you could not only calculate the distance to target, you could also detect cant except at the crossover points. Food for thought if nothing else.
  • Roswell, New Mexico
Alan

I have an Omega compressor. If you're a fellow Guild member, and you pass through Roswell, NM, I'll fill your portable tank as a courtesy.

rsterne

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Re: New Play Toy
« Reply #6 on: April 09, 2018, 12:05:32 PM »
That was essentially the concept I used, except instead of the red laser I used the scope reticle.... It has the added advantage of being calibrated via MilDots that can be converted to distance to target by using which dot the green laser intersects....

Bob
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