Subsonic cast bullets for suppressed 308

[Ken]

A friend was asking me about subsonic loads for his suppressed 308. My thoughts went to cast bullets.
Has anyone tried cast bullets for subsoncic supressed loads. If so would you share data and experiences. My first thoughts go to a 200 or 220 grain bullet with 5-6 grains of red dot or tight group. I wonder if 2400 or Unique would work? Would the big bullets even stabalize at 1000 fps or less.
thanks

[HARRYMPOPE]

Unique(my favorite) and Red dot are good with 200g bullets in the 5g to 8g range,2400 doesn't do as well for me with plainbase in 308 and 30-06 or 7.62 x 54.You shouldn't have any problem with most 200g cast bullet designs stabilizing at -1000 unless they get super pointy and long.

HMP

[JeffinNZ]

9.5gr of Trialboss under a 205gr bullet is subsonic out of "Tertles" .308 with a 21 inch barrel.

[HARRYMPOPE]

9.5gr of Trialboss under a 205gr bullet is subsonic out of "Tertles" .308 with a 21 inch barrel.

you get TB in NZ?

HMP

[redneckdan]

Trail boss is the way to go, i've done subsonic workups in several different calibers. Based on the suggestion given I would do a work up between 8.0 and 12.0gr of trail boss in .5gr increments. This will give you a good idea how that particular barrel responds to TB. I usually find a sweet spot right around 1050-1075 fps. Once you find the increment that is closest to your idea velocity then do another work up in .1gr increments for best velocity/accuracy.

[HARRYMPOPE]

11g of TrailBoss in the 7.62 x 54 with a 200g goes 1175 fps.I agree with redneckdans sweet spot for plainbase 30's though i go to 1150 with good luck.After about 1300 accuracy doesn't seem to hold up for more than 10 shots.


HMP

[303Guy]

We get some surprizing stuff in NZ. In fact, I have an idea it's made by our Auzzie cuzzies! I could be wrong there - correct me someone, please.

There are software calculators on the web that will show the required twist rates for various boolits at different speeds.

Try http://www.jbmballistics.com (http://www.jbmballistics.com/)

[Ken]

Has anyone had experience with cast bullets fouling supressors?
Great info- thanks

[redneckdan]

not any worse than what you get with a 22 rimfire. what is the suppressor construction type and material?

[JeffinNZ]

you get TB in NZ?

HMP

Yes, but we get the privilege of paying 3 times what you do even though it is made in AU.

Would you believe Alliant powder are cheaper here than ADI powders. Don't get me started.

[Ken]

It's a Yankee Hill supressor

[HARRYMPOPE]

Yes, but we get the privilege of paying 3 times what you do even though it is made in AU.

Would you believe Alliant powder are cheaper here than ADI powders. Don't get me started.

that's a bunch of ****! Sort of like when i lived close to the Shell Oil refinery and gas was the most expensive in the state in the county they produced it in.

I buy trailboss when our local hardware/discount mart has it on sale for $10.99 per jug.That's $2 off normal price there,most shops want $14-$16 locally.

HMP

[Artful]

Trail boss should do you well in 308 suppressed - be aware it can be position sensitive. (ie muzzle down the up to shoot will give different velocity than slung muzzle and and shooting uphill.

As far as cleaning a steel can you can use "DIP" as it won't eat stell like it does aluminum. Just be careful in your disposal of Lead Acetate solution (hazardous and toxic solution)

[MT Chambers]

In my .300 Whisper accuracy increased as i increased velocity, I'm sure my 185 gr. castbullets wouldn't stabilize in the 1-12" twist until i increased velocity to well beyond subsonic.

[Artful]

If he has done his homework in having a suppressed 308 host rifle I'm sure he must have at least 1:10 twist and I find cast easier to stabalize than jacketed.

[303Guy]

From JBM Ballistics

Stability
Input Data
Caliber: 0.308 in Bullet
Weight: 220.0 gr
Bullet Length: 1.000 in
Muzzle Velocity: 1000.0 ft/s
Barrel Twist: 12.0 in
Temperature: 59.0 °F
Pressure: 29.92 in Hg

Output Data
Stability: 2.818

Stability
Input Data
Caliber: 0.308 in
Bullet Weight: 220.0 gr
Bullet Length: 1.200 in
Muzzle Velocity: 1000.0 ft/s
Barrel Twist: 12.0 in
Temperature: 59.0 °F
Pressure: 29.92 in Hg

Output Data
Stability: 1.675

23/05/11 02:06, JBM/jbmstab-5.1.cgi

[nanuk]

that's a bunch of ****! Sort of like when i lived close to the Shell Oil refinery and gas was the most expensive in the state in the county they produced it in.

I buy trailboss when our local hardware/discount mart has it on sale for $10.99 per jug.That's $2 off normal price there,most shops want $14-$16 locally.

HMP


we pay almost $30 per lb up here...

[gerrycan]

We pay $35 here and we make it.go figure. Gerry[Austr]

[303Guy]

We pay $35 here and we make it.go figure. Gerry[Austr]
Hey! We pay flippin' NZ $85 over here! Holy cow! [smilie=b:

Still, it's better than sitting around watching TV. :castmine:

[Ken]

I loaded up some 200 gr jacketed with mag primers and 8.8 trail Boss for a first try. The bullet didn't make it out of the barrel. I opened the primer flashole to 9/64 as recommended. maybe it was a fluke or position sensitive got me.

[Tertle]

I loaded up some 200 gr jacketed with mag primers and 8.8 trail Boss for a first try. The bullet didn't make it out of the barrel. I opened the primer flashole to 9/64 as recommended. maybe it was a fluke or position sensitive got me.

Ken,

I recently went through the same exercise in regards to subsonic loads.i dont know if any of this may help but....

I too initially settled on o 208 gr lead WW cast projectile but didn’t like the shape of the projectile, it was a rather pointed taper and I far prefer a flat nose projectile. I am using FC brass with CCI lr primers no enlarging of flash whole, i debur but thats it.

I settled on an 180gr fn with 9.5 gr trail boss, but what I have done is use a filler. it’s a natural wool fiber filler that JeffinNZ markets.

Whilst I appreciate that some powders may not be position sensitive I am a firm believer that we make rounds as accurate and as consistent as humanly possible, I weigh and sort projectiles that I cast, weeding out visually deformed or too light a projectile, as I also do with the brass I shoot, so why wouldn’t I ensure that the powder is in exactly the same place on every round?

i dont know if that somehow has helped but ive never had a problem. I am also aware of another gunshop owner that runs a load lighter than yours (in weight of TB) and also uses a filler and that to is a extremely quiet round.

now I have also a rather large suppressor that I had custom built but the noise signature is Low I even took tome ammo of my initial 208gr ammo out when I picked up the suppressor and let the manufacturer have a go, he too was impressed.

we chrono some of the loads and according to my range book 3 rounds at 9.5 trail boss with filler with no flaring on the mouth of the case sized at .310 produced the following data 1034, 1033, 1065.so I am possibly at the top end of where I want to be for that projectile. (as well as needing to tighten up on my quality control!!)

I would like a flat nose heavier projectile as I was getting an inch group with the 208gr. i look at the bottom of the page from my range book for that day and it indicates that the 208's ''Very quiet,Very accuate''

I don’t know if any of this helps, I have a stack load of photos of targets and scribbled notes somewhere and can dig them out if you are interested
But the end result has been an accurate round with a lot of features that I like trailboss.

[Tertle]

if you have a look at the photo named '' the selection'' far right projectile is what i tried 1st off

2nd from the left is what i am currently using and the stunning brut in between is what i am progressing to.......its beyond discription and can handle a bit of presure when loaded with some ADI2206 ;)

the other photo compares fatboy on the left to a stock standard supressor that Gunworks make, and then a photo of the old girl!

[Larry Gibson]

311041 HP cast very soft of 40-1 alloy and loaded over Bullseye in well fire formed cases right at 1070 fps does the trick for me. I get a crack at 1100+ fps. It expands well out ot 100 yards on any critter of sufficient size. Accuracy runs 1.5 moa.

Larry Gibson

[Ken]

you guys are amazing!
I have a 220 grain round nose mould that iIwill try. I will also use filler in the case. I'll let you know.
thanks

[Artful]

Ken for subsonic you always want to start high and work down to velocity range you want - each barrel's coefficient of friction will differ - you can get two guns off the line and each one will want a different amount of powder to make 1050 fps. Read these

http://guns.connect.fi/gow/arcane1.html
http://guns.connect.fi/gow/arcane2.html
http://guns.connect.fi/gow/arcane3.html
http://members.shaw.ca/cronhelm/
http://www.quarterbore.net/forums/showthread.php?t=280

[Larry Gibson]

you guys are amazing!
I have a 220 grain round nose mould that iIwill try. I will also use filler in the case. I'll let you know.
thanks

I would be leary of using a filler with a suppressed gun. The filler may get stuck in the suppresser(?) or clog it eventually(?). I don't know as I developed my sub sonic rounds without a filler because of my concerns. May have been unwarrented as mentioned.

Larry Gibson

[Tertle]

Larry,

i am new to this myself and have the sneaking suspicion that you may have a hell of a lot more experience in this matter :)
(nearly 6000 posts to my 50 odd !!!!) :)

I think you are right to draw attention to the use of a filler and to be aware of what you are using, the size, composition and the like.

the fillers that i use are a small, say 10mm round natural wool fiber, it is not a cloth as such but more a dense weave of say 4mm. it is They are a product that JeffinNZ markets and so far am rather happy with. i will post a picture later but the battery in my camera has run out!!!!

the beauty of this filler is that it totally burns up and doesnt leave any residue in the barrel.

i am going to take the suppressor back in a few months to do a bit of a review with the maker so that we both get a better understanding of what is actually happening in the suppressor and any alterations or improvements that we could make.

[Larry Gibson]

Tertle

That's a dandy looking suppressed rifle you've got. Mine is Sionics, a design from the '60s, which I've had since the mid '70s. I originally had it on an M1A, then a shorter barreled .308W, a couple other rifles and now the 22" barreled .308W. I've rebuilt it twice. It is as effective as any of the newer designs with both subsonic and sonic rounds.

"i am going to take the suppressor back in a few months to do a bit of a review with the maker so that we both get a better understanding of what is actually happening in the suppressor and any alterations or improvements that we could make."

I would really be interested in your findings so please keep us posted.

Larry Gibson

[JeffinNZ]

if you have a look at the photo named '' the selection'' far right projectile is what i tried 1st off

The bullets are L - R:
Lyman 311316
CBE 316 175
Lyman 311466 flat nose conversion (poor man's Eagan)
CBE 313 215

Here is "Fatboy" and one of it's first rabbits with a 311316 the other week.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/DSCN2512.jpg

No Tertle. I wasn't calling you fat. I suspect it's a glandular thing.......

[mpkunz]

Has anyone had experience with cast bullets fouling supressors?
Great info- thanks

FWIW, I have a 44 cal rifle I shoot only as a suppressed rifle. The specs on this are that it uses .30-'06 cases cut to 1.900", so its my personal wildcat. I built an AR-15 upper in it, and I also have Turk Mauser chambered for it. Its the longest straight walled cheaply available case I could come up with, and it fits 44 cal bullets nicely. LEE was nice enough to make a double cavity 460 grain mould for me a couple years back for only $129. (You read it correctly, 460 grains !) I shoot them with 8.3 grains of Red Dot and I get 950 to 980 fps out of them. These are gas checked bullets. The lube is Thompson Red Angel. I only used that because I was given a 50 cal ammo can full of it about 10 years ago. (Nearing the end of that cache now.) The Mauser has well over 2000 rounds of this load through it with a suppressor on it. The barrel has never been cleaned and is as bright and shiny as the day I put it on the Mauser, and the can has never needed cleaning. Its still so quiet that I can shoot out in the back yard for an hour while my wife is in the kitchen with the window open and she doesn't hear me. Actually on a couple of occasions she heard me ringing an armor gong almost 200 yards away and thought it was the neighbor working outside.

Good fences make good neighbors. Get a can if your state allows it. Keeping down the noise is about being considerate when others don't want to hear the noise. If your CLEO is a d*ck, PM me and I'll go through the legal way to keep him out of the NFA loop.

[308 caster]

I have cast a lot of 308 bullets and I use 10gr of IMR 4759, A saeco by redding mold casting a 150 gr. with almost pure lead it will weigh 153 gr. The speed will be about 955fps. However If you are trying to get a cast bullet to expand or frag. upon impact I have that solution also.. Many have tried but I finally found this solution to expand cast bullets at subsonic speed and get it to frag, resulting in instant kills..

[Artful]

I have cast a lot of 308 bullets and I use 10gr of IMR 4759, A saeco by redding mold casting a 150 gr. with almost pure lead it will weigh 153 gr. The speed will be about 955fps. However If you are trying to get a cast bullet to expand or frag. upon impact I have that solution also.. Many have tried but I finally found this solution to expand cast bullets at subsonic speed and get it to frag, resulting in instant kills..

so are you heat treating the nose, or putting soft lead in the nose or is it a new trick - you did want us to beg you for the secret fomula right :-D

[nanuk]

Artful: Cryptic speak. He'd tell ya, but then...... You know

[308 caster]

so are you heat treating the nose, or putting soft lead in the nose or is it a new trick - you did want us to beg you for the secret fomula right :-D It has nothing to do with heat treating are using (soft lead) I already mentioned I was using pure lead sometimes considered (soft Lead) Although I tried heat treating about a year ago and had poor results.. I have tried everything even making solder bullets.. Mixing solder with lead only makes lead harder If you can find the bullet, you could probably load and shoot it again.

[bigted]

so put a price on it or spill yer guts bubba!!!

[nanuk]

It has nothing to do with heat treating are using (soft lead) I already mentioned I was using pure lead sometimes considered (soft Lead) Although I tried heat treating about a year ago and had poor results.. I have tried everything even making solder bullets.. Mixing solder with lead only makes lead harder If you can find the bullet, you could probably load and shoot it again.

So how do you get a boolit to expand or frag for instant kills at subsonic velocities?

inquiring minds want to know

[308 caster]

I can,t disclose how to expand or frag a cast 308 right now,as I am working on a deal with Hornandy.. However one way is to hit it with a hammer Ha , Ha Maybe Later I'll tell you

[barrabruce]

big hollow point with a split nose would probably work. Filled with grease or mercury topped off with a ball bearing or such.
I tried hollow pointing the base of my bullets to shoot backwards and try that but I couldn't get the pin in the pour spout quick enough before the lead set.
Maybe I'll have better luck some other time.

Maybe a split x nose would work. A simple split will bend at least one side and the bullet will tumble at least.

Barra

[Artful]

I remember back when I started casting someone had an article about putting thin metal foil between the blocks to make the split, I tried and found too much trouble to bother with.