.308win Subsonic Loads

butta9999 · March 7, 2010, 04:58 AM

G day, a friend of mine says he has subsonic loads for his .308win. I ask is this possible to have a safe load with subsonic verlocities in the .308win.

If this is possible could members please suggest safe starting loads. Prefer ADI or Reloader powders as IMR powders are hard to come by in Aussie Land.

Approx verlocities would also be helpful.

Cheers

SKULLANDCROSSBONES65 · March 7, 2010, 06:44 AM

G'day. My Speer No 11book shows 100gr Plinker with SR 4759 minimum load 15gr has a velocity of 1516 F/S. Not quite sub sonic but getting close

butta9999 · March 7, 2010, 09:28 AM

Yeah without saying too much it needs to be subsonic...

**Unclenick** · March 7, 2010, 11:31 AM

Plus he gave you an IMR powder number that is popular here for its bulk in lower velocity loads.

Bottom line answer is sure, it's done all the time. Best bet is a fast twist barrel and a heavy bullet so you don't have to use squib loads so small you risk detonation issues. Some guys load heavy boattails backward so the center of pressure is behind the center of gravity, which promotes stability and reduces the required spin. Poor ballistic coefficient that way, but subsonics aren't going to set any range records anyway. Lead bullets are also loaded subsonic frequently.

I think you'll find something in the neighborhood of 6 grains of AS70N (corrected per subsequent posts; sold here as Hodgdon Universal Clays) behind a 180 grain cast lead bullet will work. Buy a bag of polyester pillow stuffing and place a tuft over top of the powder in the charged case before seating the bullet. That holds the powder over the flashhole. It has very low bulk density and melts easily. Some guys fill the remaining space with it because it seems to help wipe the bore clean. I haven't tried using that much, though.

freakshow10mm · March 7, 2010, 11:42 AM

It's an IMR powder but I think it's actually an ADI made in Australia, 10gr of Trailboss behind a 180gr RN is a good load.

**Unclenick** · March 7, 2010, 12:43 PM

Their powder number AS 25 BP. This stuff is strictly for cast bullets. The warning is given repeatedly that unexpected pressure spikes have been observed when trying to make jacketed bullet loads with it. It is a good choice from the standpoint that it is bulky enough you can forget about needing fillers like the polyester.

freakshow10mm · March 7, 2010, 12:48 PM

I've shot several thousand rounds of TrailBoss subsonic handloads in both .223 and .308 using jacketed bullets and never ever had pressure spikes or any safety issues.

wxl · March 7, 2010, 01:03 PM

Re Unclenick...Correction on nomenclature

AS50 is sold here as International Clays, AS70 is Universal (AS30 is Clays)

**Unclenick** · March 7, 2010, 01:20 PM

Wxl,

Thanks for the catch. Looks like I skipped a line on my own chart. I'll stick it in below, for reference. Its taken from Hodgdon's MSDS sheets, but I have no IMR powders listed in it yet.

Freakshow 10MM,

We have a guy on another forum who's done the same. I'm just repeating what a Hodgdon tech told me as a warning. It was probably experienced with handgun rounds in revolvers, which have funny pressure curves because of the forcing cone impact, so I don't know if it would apply in rifle or not? I believe the issue was the higher start pressure from the jacketed bullets sometimes increasing the burn rate unexpectedly? Apparently, like Alliant's issue with Blue Dot, it's not explained or predictable, so they just tell people not to use it that way.

Code:

Hodgdon            |  Military  | Winchester            | Thales
                   |  & OEM     |                       | (ADI)
___________________|____________|_______________________|________
HP-38              | OBP231     | 231                   |
H110               |  WC296     | 296                   |
H414               |  WC760     | 760                   |
H380               |  WC852     |                       |
Lil' Gun           | OBP516     |                       |
Hybrid 100V        | SHP771     |                       |
HS-6               |  WC540     |                       |
H335               |  WC844     |                       |
BL-C(2)            |  WC846     |                       |
Titewad            | OBP132     |                       |
Tightgroup         | OBP242     |                       |
Longshot           | OBP473     |                       |
US869              |  WC869     |                       |
                   |  WAA90     |  WST                  |
                   | WXC170     |  WSF                  |
                   | OBP124     |  AALite (WFL)         |
                   | OBP465     |  Super-Handicap (WSH) |
                   |  WC760     |  760                  |
                   |  WC748     |  748                  |                 
                   | WMR780     |  Supreme 780          | 
                   | SMP224     |  AutoComp             |
Clays              |            |                       | AS30N
International Clays|            |                       | AS50N
Universal Clays    |            |                       | AS70N
H4227              |            |                       | AR2205
H4198              |            |                       | AR2207
Benchmark          |            |                       |  BM2
H322               |            |                       | AR2219
H4895              |            |                       | AR2206H
Varget             |            |                       | AR2208
H4350              |            |                       | AR2209
H4831              |            |                       | AR2213
H4831SC            |            |                       | AR2213SC
H1000              |            |                       | AR2217
Retumbo            |            |                       | AR2225
H50BMG             |            |                       | AR2218

butta9999 · March 9, 2010, 02:27 AM

Freakshow, 10gr of trailboss behind a 180gr bullet. Trailboss is ADI?

Do you have verlocities on this load.

Also whats your barrel twist in the .308win

SKULLANDCROSSBONES65 · March 9, 2010, 02:56 PM

G'day.

Trailboss is ADI?http://www.adi-limited.com/handloade...quivalents.asp

**Unclenick** · March 9, 2010, 03:07 PM

According to the Trail Boss MSDS at the IMR site, it is made at Mulwala, Australia by Thales, same as the other ADI powders. There are several powders referred to in the various powder MSDS's that don't appear on the ADI site. AR2215 and AR2210 are two that come to mind. AS 25 BP (Trail Boss) is just another. Probably OEM grades they feel they don't have a domestic canister grade market for, or else that they've cooked up to Hodgdon's specifications?

butta9999 · July 15, 2010, 04:38 AM

Tried working loads from 12 grains ended up at 9.5 still supersonic. This is using the 173gr cast bullet though.

I read somewhere to use 4.5gr of trailboss and use a magnum prmer. Also read to drill the flash hole out to 9/64 and get maximum ignition.

March 7, 2010, 04:58 AM	#1
butta9999 Senior Member Join Date: June 29, 2008 Location: Melbourne, Victoria, Australia Posts: 692	.308win Subsonic Loads G day, a friend of mine says he has subsonic loads for his .308win. I ask is this possible to have a safe load with subsonic verlocities in the .308win. If this is possible could members please suggest safe starting loads. Prefer ADI or Reloader powders as IMR powders are hard to come by in Aussie Land. Approx verlocities would also be helpful. Cheers __________________ Knowledge is Power!

March 7, 2010, 06:44 AM	#2
SKULLANDCROSSBONES65 Senior Member Join Date: August 19, 2008 Location: Far Nth Wst QLD Australia Posts: 992	G'day. My Speer No 11book shows 100gr Plinker with SR 4759 minimum load 15gr has a velocity of 1516 F/S. Not quite sub sonic but getting close __________________ If you're not confused, you're not trying hard enough! When you're confused, I'll try to use smaller words!!!

March 7, 2010, 09:28 AM	#3
butta9999 Senior Member Join Date: June 29, 2008 Location: Melbourne, Victoria, Australia Posts: 692	Yeah without saying too much it needs to be subsonic... __________________ Knowledge is Power!

March 7, 2010, 11:31 AM	#4
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Plus he gave you an IMR powder number that is popular here for its bulk in lower velocity loads. Bottom line answer is sure, it's done all the time. Best bet is a fast twist barrel and a heavy bullet so you don't have to use squib loads so small you risk detonation issues. Some guys load heavy boattails backward so the center of pressure is behind the center of gravity, which promotes stability and reduces the required spin. Poor ballistic coefficient that way, but subsonics aren't going to set any range records anyway. Lead bullets are also loaded subsonic frequently. I think you'll find something in the neighborhood of 6 grains of AS70N (corrected per subsequent posts; sold here as Hodgdon Universal Clays) behind a 180 grain cast lead bullet will work. Buy a bag of polyester pillow stuffing and place a tuft over top of the powder in the charged case before seating the bullet. That holds the powder over the flashhole. It has very low bulk density and melts easily. Some guys fill the remaining space with it because it seems to help wipe the bore clean. I haven't tried using that much, though. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle Last edited by Unclenick; March 9, 2010 at 12:07 PM.

March 7, 2010, 12:43 PM	#6
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Their powder number AS 25 BP. This stuff is strictly for cast bullets. The warning is given repeatedly that unexpected pressure spikes have been observed when trying to make jacketed bullet loads with it. It is a good choice from the standpoint that it is bulky enough you can forget about needing fillers like the polyester. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

March 7, 2010, 11:42 AM	#5
freakshow10mm Junior member Join Date: January 23, 2008 Location: MI Posts: 1,398	It's an IMR powder but I think it's actually an ADI made in Australia, 10gr of Trailboss behind a 180gr RN is a good load.

March 7, 2010, 12:48 PM	#7
freakshow10mm Junior member Join Date: January 23, 2008 Location: MI Posts: 1,398	I've shot several thousand rounds of TrailBoss subsonic handloads in both .223 and .308 using jacketed bullets and never ever had pressure spikes or any safety issues.

March 7, 2010, 01:03 PM	#8
wxl Member Join Date: November 8, 2005 Location: Texas Posts: 81	Re Unclenick...Correction on nomenclature AS50 is sold here as International Clays, AS70 is Universal (AS30 is Clays)

March 7, 2010, 01:20 PM	#9
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Wxl, Thanks for the catch. Looks like I skipped a line on my own chart. I'll stick it in below, for reference. Its taken from Hodgdon's MSDS sheets, but I have no IMR powders listed in it yet. Freakshow 10MM, We have a guy on another forum who's done the same. I'm just repeating what a Hodgdon tech told me as a warning. It was probably experienced with handgun rounds in revolvers, which have funny pressure curves because of the forcing cone impact, so I don't know if it would apply in rifle or not? I believe the issue was the higher start pressure from the jacketed bullets sometimes increasing the burn rate unexpectedly? Apparently, like Alliant's issue with Blue Dot, it's not explained or predictable, so they just tell people not to use it that way. Code: Hodgdon \| Military \| Winchester \| Thales \| & OEM \| \| (ADI) ___________________\|____________\|_______________________\|________ HP-38 \| OBP231 \| 231 \| H110 \| WC296 \| 296 \| H414 \| WC760 \| 760 \| H380 \| WC852 \| \| Lil' Gun \| OBP516 \| \| Hybrid 100V \| SHP771 \| \| HS-6 \| WC540 \| \| H335 \| WC844 \| \| BL-C(2) \| WC846 \| \| Titewad \| OBP132 \| \| Tightgroup \| OBP242 \| \| Longshot \| OBP473 \| \| US869 \| WC869 \| \| \| WAA90 \| WST \| \| WXC170 \| WSF \| \| OBP124 \| AALite (WFL) \| \| OBP465 \| Super-Handicap (WSH) \| \| WC760 \| 760 \| \| WC748 \| 748 \| \| WMR780 \| Supreme 780 \| \| SMP224 \| AutoComp \| Clays \| \| \| AS30N International Clays\| \| \| AS50N Universal Clays \| \| \| AS70N H4227 \| \| \| AR2205 H4198 \| \| \| AR2207 Benchmark \| \| \| BM2 H322 \| \| \| AR2219 H4895 \| \| \| AR2206H Varget \| \| \| AR2208 H4350 \| \| \| AR2209 H4831 \| \| \| AR2213 H4831SC \| \| \| AR2213SC H1000 \| \| \| AR2217 Retumbo \| \| \| AR2225 H50BMG \| \| \| AR2218 __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

March 9, 2010, 02:27 AM	#10
butta9999 Senior Member Join Date: June 29, 2008 Location: Melbourne, Victoria, Australia Posts: 692	Freakshow, 10gr of trailboss behind a 180gr bullet. Trailboss is ADI? Do you have verlocities on this load. Also whats your barrel twist in the .308win __________________ Knowledge is Power!

March 9, 2010, 02:56 PM	#11
SKULLANDCROSSBONES65 Senior Member Join Date: August 19, 2008 Location: Far Nth Wst QLD Australia Posts: 992	G'day. Trailboss is ADI?http://www.adi-limited.com/handloade...quivalents.asp __________________ If you're not confused, you're not trying hard enough! When you're confused, I'll try to use smaller words!!!

March 9, 2010, 03:07 PM	#12
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	According to the Trail Boss MSDS at the IMR site, it is made at Mulwala, Australia by Thales, same as the other ADI powders. There are several powders referred to in the various powder MSDS's that don't appear on the ADI site. AR2215 and AR2210 are two that come to mind. AS 25 BP (Trail Boss) is just another. Probably OEM grades they feel they don't have a domestic canister grade market for, or else that they've cooked up to Hodgdon's specifications? __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

July 15, 2010, 04:38 AM	#13
butta9999 Senior Member Join Date: June 29, 2008 Location: Melbourne, Victoria, Australia Posts: 692	Tried working loads from 12 grains ended up at 9.5 still supersonic. This is using the 173gr cast bullet though. I read somewhere to use 4.5gr of trailboss and use a magnum prmer. Also read to drill the flash hole out to 9/64 and get maximum ignition. __________________ Knowledge is Power!