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Incurable Tinkerer
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Just did an analysis of the effect of lighted nocks on FOC, using arrows of 20" and 22"s, four different broadheads and three versions of lighted nocks. Long story short: LIGHTED nocks reduced FOC from a low of 3.08 to a high of 4.41 percentage points, with a mean effect of 3.52 percentage points (less FOC).
The highest FOC (17.77 %) was achieved with 150 gr 3" Swhacker heads on 20" Gold Tip arrows and unlighted J nocks, with an overall weight of 400 grns. The lowest, (10.40%) with 100 gr CarniFour heads on 22" BEES and Nocturnal lighted nock. Unlighted J nocks were used for comparison throughout.
Cold, snowy winter, retired, man's gotta fiddle with crossbows somehow.
 

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I want to get lighted nock................. What would you say was your average speed difference and point of impact difference?
Lots of variables involved. On my Ravin R29, shooting 445gr. Spynal Tapps at 435fps; loss of speed is 3-5fps and drops 1 1/4" - 1 1/2" at 50 yd. with factory lighted nocks. Don't know how the Lumenok's Ravin uses compare to other lighted nocks. I'm guessing the drop in POI is due more to the increase in weight, than to the loss of speed. Others might have different results. All my testing is done at a 50 yd. indoor range.

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Incurable Tinkerer
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Discussion Starter · #4 ·
I want to get lighted nocks and start experimenting. I never would use them with vertical but I want to go there with crossbow. What would you say was your average speed difference and point of impact difference?
1 fps for 4-5 grains of increased weight. Though I'm thinking the launching speed of the arrow makes a bigger difference in POI than the weight gain in more powerful bows.
 

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Lots of variables involved. On my Ravin R29, shooting 445gr. Spynal Tapps at 435fps; loss of speed is 3-5fps and drops 1 1/4" - 1 1/2" at 50 yd. with factory lighted nocks. Don't know how the Lumenok's Ravin uses compare to other lighted nocks. I'm guessing the drop in POI is due more to the increase in weight, than to the loss of speed. Others might have different results. All my testing is done at a 50 yd. indoor range.

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I have toyed with the idea using illuminated nocks but FOC variation kinda scare me away. I shoot 100 to 125 grain broad heads and use 19 and 20" arrows.
 

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When I spoke to Jerry of South Shore Archery on the phone about custom arrows for my wickedridge rdx 400, we briefly spoke about lighted nocks. He's not a fan, doesn't use them himself and says the extra weight isn't worth how it changes the FOC.
 
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I have toyed with the idea using illuminated nocks but FOC variation kinda scare me away. I shoot 100 to 125 grain broad heads and use 19 and 20" arrows.
I can only address the testing I did for my bow. I tried the factory lighted arrows. The shafts were 20 1/4". Total weight was 400gr. with a 100gr. point and the FOC was 10.6%. Total weight of 425gr. with a 125gr. point with a FOC of 12.2%. They flew nice, but were producing 3" groups at 50yd. I didn't shoot them at longer distances.

Increased the front insert weight by 45gr., this produce a 445gr. arrow with a FOC of 16.9% with 100gr. point. Using a 125gr. point the weight was 470gr. with a FOC of 18.9%. Both of these arrows show a slight tail whip around 17 yds. They group under 3/4" inch at 50yds. and open up to 1 1/2" - 2" at 100 yds. off my tripod and 3" off hand. I can live with that.

The 445gr. arrows seemed to work the best for my setup.
 

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Lots of variables involved. On my Ravin R29, shooting 445gr. Spynal Tapps at 435fps; loss of speed is 3-5fps and drops 1 1/4" - 1 1/2" at 50 yd. with factory lighted nocks. Don't know how the Lumenok's Ravin uses compare to other lighted nocks. I'm guessing the drop in POI is due more to the increase in weight, than to the loss of speed. Others might have different results. All my testing is done at a 50 yd. indoor range.
Variables follow a pecking order dictated by physics. #1 is speed (or launch velocity); all else precedes or follows speed. Speed determines time of flight (TOF). TOF determines drop during flight. Gravity rules and is a constant acceleration toward the ground. Unless you put wings on that sucker, it's going to drop 32.2 fps per sec. #2 is energy. The more you've got, the more speed you'll get and the less time for the arrow to drop getting to the target. The mass (or weight) of the arrow only matters while it is still on the bow. The heavier the arrow, the more energy is needed to reach a given launch velocity. Mass does not matter once it has left the bow. So, you add weight, the arrow is slower and TOF is longer which gives gravity more time to make it drop. Speed, energy, and mass are variables but gravity is a constant.
 

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I saw a reference to 36 grains for a lighted nock (above) and an aluminum nock weights 20 grains(on average) so we are talking about 16 grains here. Honestly.... You cannot be serious, in suggesting that 16 grains is worth consideration as to that weight being the deciding factor, in whether to use a nock or not?
JMO.... All factory arrows are ridiculously light to begin with and standard FOC is just as ridiculous. Most people (for whatever reason) go right to the 100 grain head, so adding a lighted nock and retaining FOC is as simple as going to a 125 grain head.
End result is a better arrow for the bow, without consideration being given to the benefit of the lighted nock itself.
 
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