Suppressors Changing load to Suppressor for accuracy?

[Darkop]

I have a Gemtech Quicksand, that when I attach to my Blueprinted Remington 5R opens the groups from about .65" to 1.25" with factory ammo and my Handloads. I sent the can back to Gemtech and they couldn't find any problem with it.

I reduced my handloads and found that by reducing by .8 grains the groups tightened to .75" Which I can live with. My problem is if I use factory loads or my unsuppressed Handloads with the can, I'm back to 1.25"-1.50"

Has anyone had to reduce loads to get their can to shoot accurately?

TIA,
Darkop

 

[flyrodder]

Re: Changing load to Suppressor for accuracy?

I have done all my suppressed rifle load development with the can on. I am getting "typical" loads to work, like 175 SMKs over 45.0 of Varget, so I wouldn't say I needed to reduce the loads to get them to work. However, changes in loads result in changes in group size just like it does with unsuppressed rifles. The can would likely alter harmonics, so I wouldn't be surprised to have to develop a suppressed and unsuppressed load if you want to shoot both ways.

 

[JFComfort]

Re: Changing load to Suppressor for accuracy?

Man that sucks! The only other load I wanna develop for a suppressor is a sub sonic load. From what I have seen suppressors can be a little hit or miss. Are you shooting a .308 Win. out of a .308" can?

 

[KYS]

Re: Changing load to Suppressor for accuracy?

The Sandstorm is known to have a first round shift. How many rounds do you have thru it?

 

[Fred_C_Dobbs]

Re: Changing load to Suppressor for accuracy?

I'd be curious to learn your MVs, suppressed versus un, and how close that .8 grain drop, suppressed, puts you to the original load's unsuppressed MV.

 

[Darkop]

Re: Changing load to Suppressor for accuracy?

Flyrodder
My unsuppressed load: 45.4g Varget 175g SMK @ 2725fps= average .60" groups. Shoots an average of 1.25" with can

I have reduced the same load to 44.6g Varget and am getting an average of about .75" groups suppressed/unsuppressed. I might play with this load a little and se if I can do better.

JFComfort
Yes .308 in a .300 WM rated Quicksand

KYS338
After having the action squared and blueprinted I really don't have a 1st round shift. With the can it's just larger groups.

Fred
I don't have any Suppressed chrono data. It looks like it might be above freezing this week so I'll try to get out and get Suppressed chrono numbers

 

[Darkop]

Re: Changing load to Suppressor for accuracy?

OK, I went out today and shot through my chronograph. Here is what I got.

44.5g Varget 175 SMK W/O Can= 2670 fps average 9rds. Group size .94"
44.5g Varget 175 SMK W/ Can= 2675 fps average 10rds. Group size .74"

Hornady 168g Match factory loads open up to about 1.5" When suppressed.
Fed GMM 168 open up to about 1.25" When suppressed.
My 175g hand loads that shoot .60" open up to 1.25" When suppressed.

So there really isn't much of a difference between suppressed and non suppressed in FPS.

I guess I'll have to live with it.
Darkop

 

[Conqueror]

Re: Changing load to Suppressor for accuracy?

Suppressors do change barrel harmonics, that's a fact of life. On a different rifle you might find that the same silencer tightens the groups. It's the same reason why POI shift is unpredictable.

 

[Darkop]

Re: Changing load to Suppressor for accuracy?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Conqueror</div><div class="ubbcode-body">Suppressors do change barrel harmonics, that's a fact of life. On a different rifle you might find that the same silencer tightens the groups. It's the same reason why POI shift is unpredictable. </div></div>

unfortunately this one hasn't "tightened" groups on 3 different rifles. I'm just disappointed that I have to down load ammo to get it to shoot semi-good groups and factory ammo shoots larger than MOA on a sub-MOA gun.