Crazy factory 6.5 PRC 143 ELDX muzzle velocity with limited data points.

DisplacedHusky

Lil-Rokslider
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Sep 28, 2023
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I know the easy answer is to find a better chronograph and go back to the range, but unfortunately with family and work obligations, I will probably not be able to do that anytime soon and this has been bugging me.

Newly built Tikka 6.5 PRC with a 21” CarbonSix barrel and a SilencerCo Harvester Evo.

First trip to the range was to try a few different factory loads and get a rough 100 yard zero. My buddy had a, new to him, Labradar and could not get a reading on my rifle with the suppressor. I didn’t shoot it without the suppressor.

On the next trip to the range I firmed up a good 100 yard zero with 143 ELDX and then took it to 300 yards which was the maximum of that range. My other buddy had an older Chrony F1 and between batteries and environmental factors, only 2 shots to registered, 3034 and 3040 fps. I had initially estimated 2,800 for velocity and the rounds were impacting high from what 4dof told me to dial at 300 yards. I started “truing” the velocity and the last round, set at 3020fps was about 3/4” high at 300.

On a recent hunting trip they have steel targets on public land on the way in to an area we were hunting. Using 4dof numbers, set at 3020 fos MV, I took one shot at 500 yards and the elevation was approximately 3 inches high and the wind was correct. I took one shot at a target at 1050 yards that had a pretty stiff crosswind and according to my spotter, the elevation was correct but I had underestimated the wind. No more time for shooting as we were trying to get into an area before nightfall.

Is there any way I am getting a MV of about 3040 on a 21” 6.5 PRC barrel with factory 143 ELDX ammo or am I missing something?
 
Joined
Sep 16, 2021
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I have shot and documented around 400 rounds out of a 21" 6.5 prc. The most fast I have seen shot over a Garmin(zero failed to pick up btw) is 2970. that's a 140 grain copper creek with 140 Bergers on a very warm day.
 
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DisplacedHusky

DisplacedHusky

Lil-Rokslider
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Sep 28, 2023
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The two rounds chrono’d on mine were at about 50 rounds down the new barrel. Temps were around 50 degrees.
 
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DisplacedHusky

DisplacedHusky

Lil-Rokslider
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I have shot and documented around 400 rounds out of a 21" 6.5 prc. The most fast I have seen shot over a Garmin(zero failed to pick up btw) is 2970. that's a 140 grain copper creek with 140 Bergers on a very warm day.
I saw on their website that they have them at 2990 from a 24” barrel. Who made your barrel?
 
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DisplacedHusky

DisplacedHusky

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I was just changing altitude, temp and humidity on the 4dof app depending on the conditions I was in.
 
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When my brother put a suppressor on his T3 7mm-08 the mv of his hunting load increased significantly. No change except adding the can.

Could your suppressor be changing the equation?




P
 
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DisplacedHusky

DisplacedHusky

Lil-Rokslider
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Sep 28, 2023
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243
Could be. I probably should have shot it without the can. We were focused on diagnosing the chrono troubles.
 

Packmansion

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Sep 24, 2022
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286
sounds like a good problem to have. I wouldn't let it keep you up at night! If the Garmin says 3000+ I would buy it. I would adjust the BC rather than the velocity to calibrate your ballistics.
 
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