SilencerTalk

Sound Suppressor Discussion
It is currently Thu Apr 24, 2014 3:53 pm

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 14 posts ] 
Author Message
 Post subject: Another Trail Boss .308 experience
PostPosted: Sat Jan 31, 2009 11:34 pm 
Offline
Silent But Deadly

Joined: Sun Jun 08, 2008 9:26 pm
Posts: 348
Location: Washington State
After reading everything I could find on here about subsonic .308's I loaded a few rounds up using Lapua brass, 150 Hornady rn .30-30 bullets and 9 grains of Trailboss. I raced down to the range to just make sure the darned things would exit my monstrosity of a barrel but I didn't have a chance to chrono them.

So, the results? Well, they made it out of the tube, and hit the target.
I will probably try to chrono tomorrow with luck.

I am shooting these out of the most accurate rifle I have ever fired because it happens to be my only .308 at this exact moment. It has a 26'" 5R M-24 barrel (well, it would be an M-24 barrel except they left it long).

I used the same basic load info as another fellow here who shoots a (as I recall) 5R 22" barrel.

My initial feel is that it felt and sounded good.

More data to come...

_________________
---Something witty that makes me sound smart should be inserted here...


Top
 Profile  
 
 Post subject:
PostPosted: Sat Feb 07, 2009 9:53 pm 
Offline
Silent But Deadly

Joined: Sat Sep 20, 2008 9:22 pm
Posts: 193
Location: Missouri
Hi Muab-anything new going on with the subsonic project?


Top
 Profile  
 
 Post subject:
PostPosted: Tue Feb 10, 2009 7:09 pm 
Offline
Silent But Deadly

Joined: Sun Jun 08, 2008 9:26 pm
Posts: 348
Location: Washington State
I went to the range this last weekend with several test loads... then realized my test loads were sitting on my reloading bench still...
Shot rimfire with my son instead.

Hopefully shoot the subs next week when I get back to town. I am working with these 150 gr 30-30 bullets right now. Once I get a feel I will try shooting some 168's and see if they stabilize okay.

_________________
---Something witty that makes me sound smart should be inserted here...


Top
 Profile  
 
 Post subject:
PostPosted: Tue Feb 10, 2009 11:33 pm 
Offline
Elite Industry Professional
User avatar

Joined: Sat Apr 28, 2007 8:52 pm
Posts: 1419
Location: SE Louisiana
Don't feel bad, I went to my range today to chronograph some loads in my 77/44. I forgot the chronograph, though. :oops: At least I know the loads I had were subsonic and did exit the gun.

_________________
Shooting Supplies
Class 3/SOT
Sales, Transfers, Special orders


Top
 Profile  
 
 Post subject:
PostPosted: Wed Feb 11, 2009 12:08 am 
Offline
Silent But Deadly

Joined: Sun Jun 08, 2008 9:26 pm
Posts: 348
Location: Washington State
Landry308 wrote:
Don't feel bad, I went to my range today to chronograph some loads in my 77/44. I forgot the chronograph, though. :oops: At least I know the loads I had were subsonic and did exit the gun.


Funny. Shooting subsonics I suspect we are some of the only shooters around that are seriously checking to see if "the bullets exit the gun".

The other day at the range I ran up just as they were closing and told them I just needed to shoot a couple quick shots to see if the bullets would come out of the gun.
The two old RO's stood there staring at me slowly nodding.

Hah.

"Feller is shooting a gun to see if bullets come out...huh..."

:wink:

_________________
---Something witty that makes me sound smart should be inserted here...


Top
 Profile  
 
 Post subject:
PostPosted: Sat Mar 14, 2009 8:15 pm 
Offline
Silent But Deadly
User avatar

Joined: Thu Mar 12, 2009 10:38 am
Posts: 350
Location: The Palmetto State
I had to laugh when I saw your post.Ive been playing with the same loads, 170 grn rdnose for a 30-30 with 11.0 grns of Trailboss in my 26" custom 308. I kept pulling the bolt out to look down the barrel and two older benchrest shooters kept eyeing me...I guess it finally got to them... one came over and asked what in the world I was doing... I gota laugh right now typing this... I said making sure the bulletts are exiting my barrell. They packed up and left!


Last edited by boogyman on Sat Mar 21, 2009 8:09 pm, edited 1 time in total.

Top
 Profile  
 
 Post subject:
PostPosted: Wed Mar 18, 2009 8:38 pm 
Offline
Member

Joined: Thu Jan 01, 2009 7:59 pm
Posts: 48
--------------------------------------------------------------------------------

I had to laugh when I saw your post.Ive been playing with the same loads, 170 grn rdnose for a 30-30 with 11.0 grns of Trailboss in my 26" custom 308. I kept pulling the bolt out to look down the barrel and two older benchrest shooters kept eyeing me...I guess it finally got to them and one came over a asked what in the world I was doing... I gota laugh right now typing this... I said making sure the bulletts are exiting my barrell. They packed up and left!

This made me laugh out loud.


Top
 Profile  
 
 Post subject:
PostPosted: Wed Mar 18, 2009 11:08 pm 
Offline
Silent But Deadly

Joined: Thu Dec 13, 2007 8:46 pm
Posts: 635
Been there, done that .

Started shooting over the chrono all the time and using fresh targets so I could see the holes.

And every once and a while I need to look down the barrel.

The real fun part is shooting targets while other people are talking.


Top
 Profile  
 
 Post subject:
PostPosted: Thu Mar 19, 2009 3:45 am 
Offline
Silent But Deadly

Joined: Sun May 29, 2005 12:37 am
Posts: 4217
Location: South Sioux City, NE
In my 26" Howa I had to drop to 8grains of TB with the 150 projo. 9 was super, 8.5 super in cold temps. 8 always seems good.

_________________
NFA shooters blow their load with only one pull of the trigger.


Top
 Profile  
 
 Post subject: A few posts about my 308 load development.
PostPosted: Sat May 02, 2009 12:25 am 
Offline
Elite Member
User avatar

Joined: Thu Jul 19, 2007 11:49 pm
Posts: 3314
Location: SW NH
Below are some posts from this thread: http://www.silencertalk.com/forum/viewt ... highlight=

It should probably be here in a 308 thread instead of a 30-06 thread.
I just finished loading 50 rounds after getting my last data results. I am going to order soem more Trail Boss powder. It seems to oput perform my other pistol powders. I used to use Unique for this... No more. Trail boss has it beat hands down.


Hopefully some of this is helpful to others who are trying to work up loads for the 308. Notice how the ES (Extreme Spread) gets lower as the load density goes up.

From the other thread:

(SNIP)

The 30-06 would probably have a 1:10 twist so a 170-180 gr flat base round nose bullet would stabilize OK. The issue is the case is huge! If you have a 308 I would use that as the case if you have a 1:10 twist in a 308 hat is even better.

A 30-06 holds 70.6 gr of H2O and a 308 holds 58.9 gr of H2O Figure you will only be using 40% or less of the space in a 30-06. Compare that to 0ver 45% usage in the 308.

Trail boss has a density of .328 g/cc so a load of 9 gr in a 30-06 case would only fill 39% of the case.

8.8 gr of trail boss in a 308 with a 150 gr bullet (flat base round nose) will fill 46% of the case. It will be stable in a 1:12 and 1:10. and is subsonic.

Even that load density will cause less than stellar performance with a fairly wide range in velocity

In Winchester brass using Winchester primers 8.8 gr of Trail boss with the 150 gr Hornady 30-30 bullet gave me average vel of 961 Extreme spread of 77 fps and a SD of 30 in a 1:11.25 twist in a 22" barrel.

Next step is to go up to a 170 gr 30-30 bullet and seat it deeper to take up more case space. I suspect it will give me a better pressure curve and better more consistent velocity.


For the 30-06 I would start by using 170-180 gr 30-30 bullets (flat base round nose) Use Trail boss powder... and try 10-11 grains to start. It will probably be super sonic. Cut back .5 gr at a time till you get close then change .2 gr at a time. Target 1025-1050 FPS.

Once you get close to that... Shoot 2 or 3 5 shot strings over your chronograph and see what your #'s are. While doing that set the target up at 25 feet. check to see if your holes are nice and even. If you are sure the load is stable then use your silencer.

1100 fps is the most unstable velocity.

The 150 gr bullet out of a 1:12 has a Stability factor of 2 at 1100 fps. 1.25 is all you need.

A 168 gr SMK at 1750 fps just gets to the 1.26 stability factor. At 1100 fps it is only .68 and is very unstable. While at 800 fps it is at a stability factor of 1.04 and is considered "Marginal"

While a 180 gr flat base round nose bullet at 1100 fps in a 1:12 twist has a stability factor of 1.64 so it more than stable at sub sonic speeds in a 1:10 and 1:12 twists.

Getting a stable bullet is not the problem it's the large case capacity and the problems that causes. Trail Boss powder is light and fluffy so it will fill more of the case but STILL it is really not enough for a good burn.

I would consider the 308 case the largest I would try and use for subsonic loads. I am sure the 30-06 can work but getting it to be accurate it the problem.

===========================

OK .. You guys got me started.

I went out and got some 170 gr RN FB bullets.

I upped my charge to 8.9 gr Trail boss.

150 gr & 170 gr bullet

941 fps --- 866 fps
964 --- 875
923 --- 844
1008 --- 919
998 --- 902

AV=967 --- av= 881
ES= 84 --- es=75
SD=36 --- Sd= 29

The heavier bullet looks promising...

I ran back and loaded some new rounds

150gr -- 170 gr Bullets

9.2 gr -- 9.5 gr Trail Boss

1042 FPS - NA (leads backwards)
988 -- NA
1002 -- 965
1000 -- 957
886 ERR 930

Av=983 Av=951
SD 58 ES=35
es= 156 sd= NA


The 170 gr bullet looks good... I will bump it to 10 gr Trail Boss next time I load some more.
The 150 I will bump to 9.3 gr but I may get Super/Trans sonic "flyers." so the max may be 9.3 gr.

The 170 gr bullet is getting better/consistent pressures.

At a load of 9.5 gr we are at 50% full
At 10 gr trail boss we are at 53% full.

I don't have enough time to do another trip to my press and range before I loose light.

Maybe tomorrow I will have the best loads for the 308 using trail boss and the 170 gr and 150 gr bullets.

I suspect the 170 will be my keeper sub-sonic round till I get my whisper built.

=============================

I finally got good results with the 308

22" 5R Mike Rock GAP M700 1:11.25 twist

Winchester brass, Winchester primer

Trail Boss powder

150 gr Hornady RN Flat base and 170 Hornady RN Flat Base

I went up to 9.4 gr in the 150 bullet

998
1003
1033
1018
1007

Average= 1011 FPS, ES = 34, SD= 13

I will settle in at 9.5 gr and call it quits.

I shoots very well. All sounded consistent.
My goal was 1000 fps - 1050 fps.


The 170 gr bullet

10.5 gr Trail Boss

1056
1020
1000
986
1009
Average 1014, ES= 69, SD=26

I am going to go up to 10.7 and call it quits there.

The exterior ballistics for the 170 and 150 are very close at up to 150 yards.

Sighted in at 100 yards scope height at 1.9"... bullet path is about 3.5" high at 40-70 yards... 1.5" high at 90 yards... then 1.9" low at 110 yards. 4" low at 120 yards..

The 170 gr bullet has 325 ft lbs at 100 yards, and 299 ft lbs at 150 yards.
The 150 gr bullet has 286 ft lbs at 100 yards, and 263 ft lbs at 150 yards.

The 150 is a much softer point and will expand easily. I think the 170 is made for more rugged conditions.

For most of my applications the 150 will do. The 170 for larger critters or where I need more penetration or to knock over steel..

Rodents and raccoon size game the 150 Hornady would be a good mix.

The sound of the bullet hitting the hemlock stump was by far louder than the "report" M700 GAP AAC short Cyclone

_________________
Long distance, the next best thing to being there!


Top
 Profile  
 
 Post subject:
PostPosted: Sat May 02, 2009 12:32 pm 
Offline
Silent But Deadly
User avatar

Joined: Thu Mar 12, 2009 10:38 am
Posts: 350
Location: The Palmetto State
Absolutely outstanding data!!! Thanks John for taking the time and posting this awesome data! I have herd people using a filler(IE pillow stuffing ,cream of wheat and I think a company makes a synthetic filler for larger pistol cases). Would this be the route to go with the 30-06? Any one have some input?

_________________
Great Danger lies in the notion that we can reason with evil.....


Top
 Profile  
 
 Post subject:
PostPosted: Sat May 02, 2009 1:39 pm 
Offline
Silent But Deadly
User avatar

Joined: Wed Aug 17, 2005 11:47 pm
Posts: 4260
Location: Phx,AZ
boogyman wrote:
Absolutely outstanding data!!! Thanks John for taking the time and posting this awesome data! I have herd people using a filler(IE pillow stuffing ,cream of wheat and I think a company makes a synthetic filler for larger pistol cases). Would this be the route to go with the 30-06? Any one have some input?


Anything you put on top of the powder will get pushed into the can.
here's a review of the synthetic filler I think your thinking of .
http://www.silencertalk.com/forum/viewt ... light=puff

_________________
"Trying to tax yourself into prosperity is like standing in a bucket and trying to pick yourself up by the handle." - Winston Churchill


Top
 Profile  
 
 Post subject:
PostPosted: Sat May 02, 2009 2:06 pm 
Offline
Elite Member
User avatar

Joined: Thu Jul 19, 2007 11:49 pm
Posts: 3314
Location: SW NH
case fillers work but have some serious disadvantages. Dacron(sp) fiber fill is often used, also cotton balls pulled apart, and for uniformity single ply toilet paper cut into 1/4s http://www.reloadammo.com/rel-location.htm

The issue is movement of the powder. Even if you had a filler that burned completely the powder would move around when handled. Eventually causing inconsistent ignition.



http://www.mcace.com/adapters.htm They have adapters that you could use.. I believe they have one that shoots a 7.62x39 in a 30-06

I would not locktite it in but in a bolt gun this might really work well.

This guy used one for a 7.62x39 in a 308

http://www.surplusrifle.com/reviews/tig ... /index.asp

That would be good... you could use the small case and shoot heavy bullets.

Just another way to work around the problem.

_________________
Long distance, the next best thing to being there!


Top
 Profile  
 
 Post subject:
PostPosted: Sat May 02, 2009 4:53 pm 
Offline
Silent But Deadly
User avatar

Joined: Thu Mar 12, 2009 10:38 am
Posts: 350
Location: The Palmetto State
Oh no I smell another project coming!!!! I built my son a 7.62x39 bolt gun four years ago to hunt with. He shot his first deer at 7 with it. I built it with a .308 size barrel so I could handload regular .30 cal bullets in it. Got plenty of brass for it. Ill order an adaptor Monday. Did you see the .32 acp adaptor for .308? By the way thanks for the info! My bride will not like it though.....more gunstuff? I can here it now!Image

_________________
Great Danger lies in the notion that we can reason with evil.....


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 14 posts ] 

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: bani, XLmoby and 70 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group