First Suppressor, First Impressions. And losing velocity?

Mark @ Exo

Well-Known Member
Joined
Apr 25, 2020
Messages
96
Location
Here to Learn...
After a 6-month wait, the ATF let me have my Thunderbeast Ultra 7 30-Cal. Some of my findings on POI shift, accuracy and velocity on my Tikka...


Accuracy and repeatability of zero after removing and reinstalling the suppressor are great. POI shift with and without the can is about 2.25-2.5"

What surprised me most was the velocity loss of about 10fps with the can. That's contrary to the slight increase that seems to be most common when shooting suppressed. Anyone else see velocity loss with a suppressor?

Small sample sizes here, but I have shot again since this video and had similar results.
 

woodnut

Well-Known Member
Joined
May 5, 2009
Messages
936
Location
roanoke,va.
From my experience, your results are on par. I do , however, usually get better accuracy with the can. Knowing barrels are flexible, I bet the POI shift is caused by the wt. of the can as well as a change in harmonics.
 

AKironhead

Member
Joined
Sep 21, 2017
Messages
18
Location
Alaska
Great vid and great build! With my 24" proof I get about a 1" poi shift with an ultra 7 and gain an avg of 15fps with a 6.5 creedmoor. I have used an Ultra 7 on 6 different rifles and all have had varied impact shifts do to harmonics as woodnut stated but all of them had an increase in fps typically in the 10-20 fps range. A short barreled .260 rem however had an increase of 40 fps so may have more to do with barrel length and powder burn rate/charge weight. As long as the poi is repeatable you're good to go. Here is a vid where I shoot round robin style taking the Ultra 7 off every other round and correcting for the offset
[youtube]
[/youtube]
 

Mark @ Exo

Well-Known Member
Joined
Apr 25, 2020
Messages
96
Location
Here to Learn...
Great vid and great build! With my 24" proof I get about a 1" poi shift with an ultra 7 and gain an avg of 15fps with a 6.5 creedmoor. I have used an Ultra 7 on 6 different rifles and all have had varied impact shifts do to harmonics as woodnut stated but all of them had an increase in fps typically in the 10-20 fps range. A short barreled .260 rem however had an increase of 40 fps so may have more to do with barrel length and powder burn rate/charge weight. As long as the poi is repeatable you're good to go. Here is a vid where I shoot round robin style taking the Ultra 7 off every other round and correcting for the offset

Thanks for the info and video. I'll be running this Ultra 7 on a 20" 6.5 Creed as well, and am very interested to see the results for that rifle.
 
D

Deleted member 103481

Guest
Sounds right, I think most expect a slight velocity increase but it’s overblown
 

cohunt

Well-Known Member
Joined
Jan 21, 2016
Messages
2,715
Location
Colorado Springs, CO
i have noticed that poi change is shooter dependent--which leads me to believe that it is partially contributed to how the individual shooter handles the recoil and recoil impulse.
I find that in every one of my rifles with every shooter with my suppressors the suppressor always shoot lower than un-suppressed --but the amount of vertical shift changes with each shooter--I mainly think this is attributed to the slight reduction in recoil, and the way it recoils an how the shooter handles that change in recoil
I agree that some of the poi shift is in the can itself, but I think some resides in the individual shooter also
 

AKironhead

Member
Joined
Sep 21, 2017
Messages
18
Location
Alaska
i have noticed that poi change is shooter dependent--which leads me to believe that it is partially contributed to how the individual shooter handles the recoil and recoil impulse.


That's an interesting data point and makes a lot of sense. I'll have to test that out on a few folks.
 

woodnut

Well-Known Member
Joined
May 5, 2009
Messages
936
Location
roanoke,va.
Hard to argue that point about poi change is sometimes the shooter. I still maintain though that the wt of the can and better harmonics contributes more to change in poi and accuracy. But still, a good point about each shooter. For instance, and not about cans, but I can zero my rifle perfectly and two shooters can get behind it and get a very different poi!
 

Primary

LRH Assistant
Here are some related products that LRH members are talking about. Clicking on a product will take you to LRH’s partner, Primary, where you can find links to LRH discussions about these products.

 
 
Top