Shotmarker - in a indoor setting

[Left_to_lobster_2020]

Hopefully I posted in the right spot, I actually came across the site from googling the topic and just became a member.

My local range has just completed building indoor/heated shooting tubes. We have a 100 and (2) 200 yard ranges. Each range has a shot marker setup. I’m shooting a lot more using these tubes given 10-32F weather here in Michigan. I find these setup’s as amazing investments. A couple of questions:

• When googling I noticed people say accuracy of shots/data can be impacted by elements out doors - in the open. I haven’t seen anything on my ranges setup - totally enclosed concrete shooting tubes - each range has its own tube. How accurate will the data be in this scenario?

• I noticed Shotmaker doesn’t advertise any accuracy with ES/SD/average FPS, neither does anyone online from a googling search. I did some chronograph testing initially with my magneto speed sporter. My .223 data in Strelok Pro vs the Shotmarker showed a ~ 130 FPS gap at 200y. From what I read I need to stick with the magneto speed for app work to build tables. Even in the indoor setting?

• I’ve shot every weekend for the past month. I shot my best group ever at 200y this weekend with M77 FTW in 30-06. I shot a .45” - 3 shot group with Hornady Precision Hunter factory ammo. My Accubond deer reloads shot as expected. I felt like I won a national championship in football with those Hornadys. Using Strelok back calculation based on the average FPS - puts me at 2904 FPS at the muzzle with a 24” barrel. Hornady advertised 2750 FPS at the muzzle with a 24” barrel. If the FPS is in accurate would you trust the group?

 

[Walt Krafft]

Welcome to the forum. The velocities measured by the Shotmarker are not very accurate in an absolute sense. They have not been calibrated for speed accuracy. They can vary with conditions and between units. Inside there may be a lot of echos messing with the system. Ask Adam, he will know. As far as advertised velocity, who knows how accurate it is.

 

[jepp2]

My local range has just completed building indoor/heated shooting tubes.

Interesting. Did they install them for your comfort or to meet regulations to keep the range operating?

From what I read I need to stick with the magneto speed for app work to build tables

Don't count on the Shotmarker velocities at all. Even your magneto speed accuracy is only claimed to be 99.5%. And isn't your ballistic program only using a single BC value? The BC changes with the velocity change. The adjustment you made is correct for your rifle.

If the FPS is in accurate would you trust the group?

This is my own personal opinion. The only thing a 3 shot group tells me is if a load will not shoot. I never put any trust in what a 3 shot group shows me. I want to see 5 shot groups repeated to determine the true accuracy potential for the load I am working with. In the Bulletin section of the forum Sierra provides a very good explanation.

Welcome to what I consider the BEST forum available.

sierra flyers « Search Results « Daily Bulletin

bulletin.accurateshooter.com

 

[Dave M.]

Interesting. Did they install them for your comfort or to meet regulations to keep the range operating?


Don't count on the Shotmarker velocities at all. Even your magneto speed accuracy is only claimed to be 99.5%. And isn't your ballistic program only using a single BC value? The BC changes with the velocity change. The adjustment you made is correct for your rifle.


This is my own personal opinion. The only thing a 3 shot group tells me is if a load will not shoot. I never put any trust in what a 3 shot group shows me. I want to see 5 shot groups repeated to determine the true accuracy potential for the load I am working with. In the Bulletin section of the forum Sierra provides a very good explanation.

Welcome to what I consider the BEST forum available.

sierra flyers « Search Results « Daily Bulletin

bulletin.accurateshooter.com

Based on his location, I’m certain he’s speaking of the tube ranges that were installed in Midland, Michigan. I’ve found them to be very accurate and I can shoot similar sized tiny .150-.225” 5 shot groups at 100 yards in the tubes as I can at 100 yards on standard BR target paper.
Dave

 

[9146gt]

Based on his location, I’m certain he’s speaking of the tube ranges that were installed in Midland, Michigan. I’ve found them to be very accurate and I can shoot similar sized tiny .150-.225” 5 shot groups at 100 yards in the tubes as I can at 100 yards on standard BR target paper.
Dave

Is that Duncan's range?
Tom

 

[Dave M.]

Is that Duncan's range?
Tom

Not sure what Duncan’s range is but I’m thinking that he is referring to the midland county sportsman’s club.