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Subsonic .308
- Thread starter onechance
- Start date
Re: Subsonic .308
lots here on it, search, get some trailboss and 180RN bullets. Dirty powder but it works... very well!
lots here on it, search, get some trailboss and 180RN bullets. Dirty powder but it works... very well!
Re: Subsonic .308
Go with the heavy bullets like the 210-240 class bullets. If they don't stabilize nose first, stick them in the case backwards.
Try Trailboss and start high (for the 220's in a 308 you should start at 10.5gr and work down in 0.2gr incrememnts).
Or try Red Dot and start with about 11.5gr in the case and work down in 0.2gr increments. You will probably need a cottonball filler for the powder. If you seat the bullets backwards and deep they will take up a lot of the case capacity and reduce the chance of a SEE without the cotton filler.
Do not approach subsonic load testing with the suppressor attached to the rifle, this type of testing should always be done with the can off the gun first. Once they're proven stable on paper at 100-200yd then you can put the suppressor back on there.
Go with the heavy bullets like the 210-240 class bullets. If they don't stabilize nose first, stick them in the case backwards.
Try Trailboss and start high (for the 220's in a 308 you should start at 10.5gr and work down in 0.2gr incrememnts).
Or try Red Dot and start with about 11.5gr in the case and work down in 0.2gr increments. You will probably need a cottonball filler for the powder. If you seat the bullets backwards and deep they will take up a lot of the case capacity and reduce the chance of a SEE without the cotton filler.
Do not approach subsonic load testing with the suppressor attached to the rifle, this type of testing should always be done with the can off the gun first. Once they're proven stable on paper at 100-200yd then you can put the suppressor back on there.
Re: Subsonic .308
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: onechance</div><div class="ubbcode-body">Trailboss is very unpredictable for me. I don't know if it's due to the weather or location. Sometimes I hear a sonic crack or I get a poof and a bullet stuck in the barrel. </div></div>
TB fills case volume great but it's still sensitive to (case volume filled) & needs minimum of 40% volume filled on the .308 case to be consistent on the burn rate .
Use a deeper seating depth than your normal .308 OAL seating for the length of Magazine . Deeper on the bullet seating will eat some case volume up & will help consistent burn on the TB powder on the subsonic .
.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: onechance</div><div class="ubbcode-body">Trailboss is very unpredictable for me. I don't know if it's due to the weather or location. Sometimes I hear a sonic crack or I get a poof and a bullet stuck in the barrel. </div></div>
TB fills case volume great but it's still sensitive to (case volume filled) & needs minimum of 40% volume filled on the .308 case to be consistent on the burn rate .
Use a deeper seating depth than your normal .308 OAL seating for the length of Magazine . Deeper on the bullet seating will eat some case volume up & will help consistent burn on the TB powder on the subsonic .
.
Re: Subsonic .308
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">
Or try Red Dot and start with about 11.5gr in the case and work down in 0.2gr increments. You will probably need a cottonball filler for the powder. If you seat the bullets backwards and deep they will take up a lot of the case capacity and reduce the chance of a SEE without the cotton filler.</div></div>
Several years ago, I loaded some .308s with a low dose of Red Dot and, I believe, 150g FMJs for firelapping. With no can, they were very quite and IIRC accurate beyond what I expected. I am thinking they were under 1moa.
bohem, how do you use the cotton filler? Do you pack it in, loose fit, how much, etc.?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">
Or try Red Dot and start with about 11.5gr in the case and work down in 0.2gr increments. You will probably need a cottonball filler for the powder. If you seat the bullets backwards and deep they will take up a lot of the case capacity and reduce the chance of a SEE without the cotton filler.</div></div>
Several years ago, I loaded some .308s with a low dose of Red Dot and, I believe, 150g FMJs for firelapping. With no can, they were very quite and IIRC accurate beyond what I expected. I am thinking they were under 1moa.
bohem, how do you use the cotton filler? Do you pack it in, loose fit, how much, etc.?
Re: Subsonic .308
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: nashlaw</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">
Or try Red Dot and start with about 11.5gr in the case and work down in 0.2gr increments. You will probably need a cottonball filler for the powder. If you seat the bullets backwards and deep they will take up a lot of the case capacity and reduce the chance of a SEE without the cotton filler.</div></div>
Several years ago, I loaded some .308s with a low dose of Red Dot and, I believe, 150g FMJs for firelapping. With no can, they were very quite and IIRC accurate beyond what I expected. I am thinking they were under 1moa.
bohem, how do you use the cotton filler? Do you pack it in, loose fit, how much, etc.? </div></div>
I use it when % fill of the airspace (when the bullet is seated) drops below 70%. I use cotton and I lightly pack it, just enough so I'm comfortable with the powder being up against the primer with regular day to day handling.
The polyester fill I've used in an old 7.62x54R with Red Dot and found some burned plastic looking residue in the throat which I assumed to be latent residue from the poly-fill. I have just started using cotton or gun cotton instead.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: nashlaw</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">
Or try Red Dot and start with about 11.5gr in the case and work down in 0.2gr increments. You will probably need a cottonball filler for the powder. If you seat the bullets backwards and deep they will take up a lot of the case capacity and reduce the chance of a SEE without the cotton filler.</div></div>
Several years ago, I loaded some .308s with a low dose of Red Dot and, I believe, 150g FMJs for firelapping. With no can, they were very quite and IIRC accurate beyond what I expected. I am thinking they were under 1moa.
bohem, how do you use the cotton filler? Do you pack it in, loose fit, how much, etc.? </div></div>
I use it when % fill of the airspace (when the bullet is seated) drops below 70%. I use cotton and I lightly pack it, just enough so I'm comfortable with the powder being up against the primer with regular day to day handling.
The polyester fill I've used in an old 7.62x54R with Red Dot and found some burned plastic looking residue in the throat which I assumed to be latent residue from the poly-fill. I have just started using cotton or gun cotton instead.
Re: Subsonic .308
take it with a grain of salt. and do your own work up.
1/10 twist powder Hodgdon Titegroup
5.5 gr 150fmj just for plinking havent shot them past 50yds but they were shooting good and very quite.
6 gr 168amax same as above
I havent had any problems with the 150fmj's being that they are a light bullet for the twist rate
also with the titegroup i have not had a problem with the case beight to empty i use no other filler and no issues. hodgdon has some subsonic loads on their website.
take it with a grain of salt. and do your own work up.
1/10 twist powder Hodgdon Titegroup
5.5 gr 150fmj just for plinking havent shot them past 50yds but they were shooting good and very quite.
6 gr 168amax same as above
I havent had any problems with the 150fmj's being that they are a light bullet for the twist rate
also with the titegroup i have not had a problem with the case beight to empty i use no other filler and no issues. hodgdon has some subsonic loads on their website.
Re: Subsonic .308
With the faster twist barrel, I would be trying IMR SR 4759 with 210 or 220 grain bullets.
http://www.snipershide.com/forum/ubbthre...rue#Post1797498
With the faster twist barrel, I would be trying IMR SR 4759 with 210 or 220 grain bullets.
http://www.snipershide.com/forum/ubbthre...rue#Post1797498
Re: Subsonic .308
Didn't notice the twist... like others have said with fast twist barrels the 220RN worked well for me. Plus they take up lots of room!
It has been mentioned in other threads but I didn't clarify the RN bullets are shorter and thus are 'safer' less chance of a baffle strike with an unstable bullet. Do not test loads with the supp on!
My results with the Red Dot were not that great very temp sensitive.
I have stayed away from fillers but I hear Cream of Wheat works with zero residue.
Didn't notice the twist... like others have said with fast twist barrels the 220RN worked well for me. Plus they take up lots of room!
It has been mentioned in other threads but I didn't clarify the RN bullets are shorter and thus are 'safer' less chance of a baffle strike with an unstable bullet. Do not test loads with the supp on!
My results with the Red Dot were not that great very temp sensitive.
I have stayed away from fillers but I hear Cream of Wheat works with zero residue.
