Hi,
what is the best way to make a good cartridge for a silenced .308Win rifle, i.e. to get as good a punch as possible with as little noise as possible. I guess sub-sonic is required(?) and then just to get as heavy a bullet you can get for that cartridge and load it at about 330m/s?

GE,

I don't have any first hand experience but there is some interesting reading around this site.

http://guns.connect.fi/gow/gunwriters.html

Lot's of interesting reading, thanks!

GE,

You should post the question in the European Forum, ans many stalkers in the UK use sound moderated rifles. I know a few guys that use 243, 270, 308win and 30-06 moderated so you should get some good advice.

On a Supersonic load the moderator will take some of the noise out of the bang, but it can't do anything about the sonic boom. If you go subsonic, then you solve that problem but may cause yourself other issues depending on what you use the rifle for.

Which mderator are you looking at?

Rgds,
FB

What is the twist rate of your barrel? That is a serious issue as larger bullets may not stabilize, and then you have to keep going down in size until you find one that does stabilize in your rifle at subsonic velocities.

quote:

Originally posted by Fallow Buck:
GE,

You should post the question in the European Forum

Which mderator are you looking at?

Rgds,
FB

I'll try there aswell. This is for a friends rifle, I do not know if it is a commercial one or home made. Posted here to start learning about the subject before getting into the details.

quote:

Originally posted by Mark:
What is the twist rate of your barrel? That is a serious issue as larger bullets may not stabilize

Thanks for the heads-up. I do not know the twist rate right now, it's a friends rifle. What is the heaviest .30 bullets available? I vaguely remember seeing 225gn but guess there can be heavier available...

quote:

one that does stabilize in your rifle at subsonic velocities.

Then you have to ask if the bullet will expand at that velocity (assuming you are hunting with it).

LWD

I have and reload for a 300-221 Fireball aka 300 Whisper.
First off, Sierra makes a 240 gr HPBT and that is about the heaviest easily obtainable bullet out there.
You need a fast twist barrel usually accepted to be around 1:7 or 1:8 to stabilize that weight.
If the twist is slower, it is doubtful the bullet will stabilize and accuracy goes to hell in a handbasket NOT to mention that you are very likely to strike the baffles in the "can" or sound suppressor. This occurrence will not make you a happy camper considering g the cost and paperwork of the suppressor.

At subsonic velocities there is virtually NO expansion of the bullet but in actual hunting scenarios the bullet appears to yaw or tumble in deer sized game and quick kills of whitetail deer is very achievable with a well placed shot.
Since subsonic rounds never, by definition, go transsonic they tend to be inherently more stable and maintain velocities near their launch velocity much much longer than supersonic rounds.
In the Whisper, if my muzzle velocity is 1050 fps, it is still in the 940 fps to 960 fps at 200 yards.

One other note, if you do shoot supersonic, ie, regular rounds through a suppressor, the crack is still heard but it does not seem to affect the game as usual as they do not seem able to delineate the direction of the shot.

I have acquaintances who have had the rounds intentionally shot over them while they were in the 200 yard "pit" on the range and although they heard it they were not able to figure out the direction or distance- they said it was like a jet sonic boom but without directionality.
Hope it helps.

Gary

Gab,
thank's for your input. The barrel twist, I assume you mean in subsonic bullet velocities(?).

I am thinking regarding the relatively low velocity reduction at 200 yards that it is a non-linear relationship, i.e. air resistance increases more than 1:1 with velocity which is good.

The main "interest" here is not the game experience of the shot noise but to minimize the noise range, guess someone may be wondering "why" but the reason is "local wildlife policies" (nuff said).

Spent Brass Cases !. I couldn't resist !.

Haven't a clue illegal over
my way .
Good Luck .

Shoot Straight Know Your Target . ...

Goran,

Here is a tidy article that I forgot was in my bookmarks. Again, I cannot vouche for any of this stuff from my own experience.

http://members.shaw.ca/cronhelm/DevelopSubsonic.html

Edit: One thing I can add from experience. If you try any loads using pistol/shotshell powder, I suggest you weigh the charged cases before seating bullets and weigh the loaded rounds to be certain that a little too much powder did not find it's way into any of your cases. I have found that visually inspecting the powder level is not very effective.

GE,
the twist rate really is related to the length of the bullet. Usually the longer the bullet the heavier it is and the faster the twist needed to adequately stabilize.
With the advent of the all copper bullets(Barnes) they tend to be longer than a conventional lead core bullet and they too will do better in a bit faster twist if you get up to the top weights but mainly due to bullet length.

quote:

Originally posted by John in SC:
Goran,

Here is a tidy article that I forgot was in my bookmarks. Again, I cannot vouche for any of this stuff from my own experience.

http://members.shaw.ca/cronhelm/DevelopSubsonic.html

Thanks!