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Posted: 7/28/2007 4:59:01 PM EDT
Well, just got my Jet .308 Titanium suppressor this week. I had some 180 grain Black Hills SMK subsonics I bought from my dealer, and I hurriedly shot 5 rounds at the ranch last week, just to check it out.

The sound? Just a firing pin, a little swoosh, and the TANG! sound of the bullet striking my sillouhete. I am totally impressed with it. I believe they have improved their design recently, because this is definitely the most quite Jet I have ever heard. Yeah, it took a long time to get it, as their turn around is a little slow....but I think it was worth the wait. In their defense, they just built a 4500 square foot storefront, and put in CNC machines, etc.

Can anyone tell me just how big a bullet I can get in the .308 case for subsonic reloads, and still have the bearing surface appropriately seated, whilst not compressing powder, having OAL issues or causing erratic flight? I will need the heavy bullet to kill feral hogs at my protein feeders. These are big beasts.

I just ordered 200 bullets, a hundred of the 180 grain SMK's because I knew they'd work, and then I also ordered some of the 180 grain round noses, because that is what TTi is loading. Can I get away with the 200, 210 or 220gr.??

I have a custom made Mike Rock 5R barrel in a Remington action, trued & pillar bedded, with 1 in 10 twist, and Jewel Trigger.

If I neeed to move this over to ammo, then so be it. I have pretty good expierience with suppressors, but not enough with reloading, and even the Sierra guys couldn't answer ths. Thanks for any help.
Link Posted: 7/28/2007 6:42:47 PM EDT

Originally Posted By silentbushmaster:
I have good luck and accuracy with a 170 Hornady RN and Trail Boss powder.


Thanks very much, that's useful information!

Link Posted: 7/29/2007 6:27:50 AM EDT
Its not the weight of the bullet that matters , its the length
And second what is the twist of your barrel
A round nose can be heavy but still short enough to be stabilized
if you have a 1in 10twist you might use 200smk but test without the can haveStart at 11gr this will all most for sure be supersonic ,but it is better to start that way and later work the load down ,this way you will not end up with a bullet stuck in the barrel You all so have to clean the barrel more often ,as the loads is more senticive for a dirty barrel
Link Posted: 7/29/2007 8:32:42 AM EDT
[Last Edit: 7/29/2007 8:35:05 AM EDT by hi-tech-rancher]

Originally Posted By Wolfdk:
Its not the weight of the bullet that matters , its the length
And second what is the twist of your barrel
A round nose can be heavy but still short enough to be stabilized
if you have a 1in 10twist you might use 200smk but test without the can until you know for sure
I have used n110(powder from Finland )burns clean under lower pressure ,and no need for filler
Start at 11gr this will all most for sure be supersonic ,but it is better to start that way and later work the load down ,this way you will not end up with a bullet stuck in the barrel
You all so have to clean the barrel more often ,as the loads is more senticive for a dirty barrel




Thanks very much....good info.

....and please see previous post. It is 1 in 10" as I expected to use both full-power and SS loads.


Well, just got my Jet .308 Titanium suppressor this week. I had some 180 grain Black Hills SMK subsonics I bought from my dealer, and I hurriedly shot 5 rounds at the ranch last week, just to check it out.

The sound? Just a firing pin, a little swoosh, and the TANG! sound of the bullet striking my sillouhete. I am totally impressed with it. I believe they have improved their design recently, because this is definitely the most quite Jet I have ever heard. Yeah, it took a long time to get it, as their turn around is a little slow....but I think it was worth the wait. In their defense, they just built a 4500 square foot storefront, and put in CNC machines, etc.

Can anyone tell me just how big a bullet I can get in the .308 case for subsonic reloads, and still have the bearing surface appropriately seated, whilst not compressing powder, having OAL issues or causing erratic flight? I will need the heavy bullet to kill feral hogs at my protein feeders. These are big beasts.

I just ordered 200 bullets, a hundred of the 180 grain SMK's because I knew they'd work, and then I also ordered some of the 180 grain round noses, because that is what TTi is loading. Can I get away with the 200, 210 or 220gr.??

I have a custom made Mike Rock 5R barrel in a Remington action, trued & pillar bedded, with 1 in 10 twist, and Jewel Trigger.

If I neeed to move this over to ammo, then so be it. I have pretty good expierience with suppressors, but not enough with reloading, and even the Sierra guys couldn't answer ths. Thanks for any help.




Link Posted: 7/29/2007 9:59:38 AM EDT
Your best bet with your 1-10 would be a 180gr round nose flat base with about 11.5 of trailboss as a start out and work your load up or down depending if it is subsonic out of your bbl. The flat base tends to be more accurate out of a 1-10. I have tried 160-170-180-190-200-210gr flat base and 168-175-180-190and 200 gr smk's and the 180's do by far work the best and are far more accurate. The 190 200 and 220gr smk's are more for a 1-8 twist.
Link Posted: 7/29/2007 2:27:37 PM EDT
Subsonic rounds are good for impressing friends and for doing demo's to show how quiet the suppressor can be, but that's about it. They typically lack the same precision as full power loads (average about 1MOA), so making the same quality practice isn't very practical and I wouldn't hunt with one when I can do it more humanely with a full power round.
They are kind of fun to play with though and component selection is critical.

-Brass-Choose brass that has the lowest internal capacity. This means using Federal GMM, Lapua or MilSurp brass that you've sorted by weight to remain consistant. Brass from Winchester or Hornady has a relatively large capacity as far as .308 goes. The key is to be able to fill it up without much room to "slosh".

-Bullets-Choose something with a round nose and a flat base. BoatTails don't seem to work very well at lower velocities and the different bullet provides instant visual identification as to what type of round it is. I like using the Remington 170grn .30-30 bullets seated to the cannelure. The extra seating depth eats into the powder reservoir further reducing the ability for the powder to "slosh". I've also used the Remington 180grn PSP's and Nosler 180grn Accubond's, getting the best results accuracy-wise with the Accubonds.

-Primers-I used CCI large rifle primers just because I had a ton of them on hand. They worked well.

-Powder-The only powder I've worked with has been Trailboss. It's worked so well and takes up enough space to minimize any sloshing that I haven't played with anything else. The key thing for picking powder is to pick something that will give you a fairly conisistant powder column.

Having a chronograph available is critical for working up subsonic loads. The last thing you want on a precision rifle is a stuck barrel. If that happens you might as well get a new barrel because the obstructed barrel is toast.
When working with factory rifles (Remington PSS/LTR, Savage 10/12's and FN SPR's) I would suggest starting at 11.5grns of Trailboss and reducing the loads in .3grn increments until you get into the 1035fps range. With custom rifles, start at 10.5grns and work down.

I've only worked down loads for .308 subsonic loads on custom rifles and the results will vary from rifle to rifle. I've had friends that have been subsonic at 10.7grns on their factory Savage and Remington's and I've been down to 9grns of Trailboss on my custom with a Schneider barrel. The point is that whatever load you work on, keep it for that rifle only and don't use it in another rifle until you've had the chance to do proper load developement with it.
Link Posted: 7/29/2007 2:41:51 PM EDT
I have a Howa 24" with an AAC Cyclone, with the 1/12 twist I have been sticking with www.berrysmfg.com/386.php for bullets, I would disagree with the above poster the accuracy at 100yds is everything that it is with full power loads shooting 168gr Sierra match kings.

It the same power as a 9mm rifle with flatter trajectory and a bit more velocity down range. I am using 9 gr of Trail Boss but I need to bump it up just a bit.
Link Posted: 7/29/2007 2:44:28 PM EDT
[Last Edit: 7/29/2007 2:48:25 PM EDT by Spooky130]
Does anyone have experience using the Lapua 200 grain bullets designed for subsonic velocities? I picked some up the other day and they are of an unusual design.

I've been looking into this as well and one poster on "that other site" suggested moly coating all your bullets to help to prevent them getting stuck.

Right now I think I've settled on using once fired Federal brass, large rifle magnum primers, 200 grain Lapuas, and Trailboss.

How critical is a chronograph? I don't have one...

Spooky
Link Posted: 7/30/2007 4:39:24 AM EDT
[Last Edit: 7/30/2007 4:40:16 AM EDT by PHD]
Link Posted: 7/30/2007 5:02:23 AM EDT
tag
Link Posted: 7/30/2007 12:29:26 PM EDT

Originally Posted By Green0:
I had heard this:

Boat-tails are a hindrance below the speed of sound, as they will yaw 180 degrees in order to fly BASE first. That 180 degree phenomenon can cost some accuracy.

The round nose, flat based ammo will not.


I figured that would be why TTI and EBR use the round nose ammo. That and the obvious fact the round nose ammo often is expanding ammo.

Hinelines experience seems to contradict that so maybe that's innaccurate?


I am not using BT bullets in my subsonic loads, so I do not understand your comment.
Link Posted: 7/30/2007 12:40:14 PM EDT
tag
Link Posted: 7/31/2007 10:34:17 AM EDT
Link Posted: 7/31/2007 4:44:02 PM EDT

That and the obvious fact the round nose ammo often is expanding ammo.

No conventional rifle bullet regardless of size or shape will expand at subsonic velocity. Even a huge hollow point bullet will act as a solid at low velocity.

Subsonic projectile weight is almost irrelevant because the medium weight stuff will over penetrate just about any soft target you choose to shoot it at and thus waste most of its "energy". Using heavier bullets just means you will be wasting more "energy" when the bullet comes flying out the backside of whatever you are shooting at.

Link Posted: 8/1/2007 5:14:11 AM EDT
[Last Edit: 8/1/2007 5:14:41 AM EDT by PHD]
Link Posted: 8/2/2007 5:51:44 PM EDT
I just got in some EBR today.
I am shooting it through a FN SPR.
I did a safety check today for instability due to my slow twist barrel, 1:12.
No problems with keyholing and it has consistent grouping.
I will shoot some rounds at really close range as a double check as well this weekend.
I will dig out some rounds and get some pics to post to see if they really do expand.
I will be shooting into a hard Oklahoma clay backdrop.
I may try shooting into some soft clay/mud at a pond edge too.
Link Posted: 8/2/2007 6:28:31 PM EDT
I checked the EBR out and it is expensive, but I definitely will try some.

I also received the 180 grain Sierra Pro hunter round nose, flat base bullets and the 180 grain SMK's from Midway today. Loads to be developed in the next week. I'll post back when I can get out to shoot some.

Please keep us posted on your test results. Maybe shoot at a few phone books?
Link Posted: 8/2/2007 7:30:17 PM EDT
I dropped a line to my suppressor manufacturer to make sure it is o.k.
I should get my suppressor in the next week or 2 at the latest.

What kind of press are you all using for reloading.
I have zero experience or equipement but I am interested in getting started.
I am definitely collecting the brass
Link Posted: 8/4/2007 4:07:38 PM EDT
I worked some up and got to give them a go today. I had no stability problems and the sound, or lack of, was just awesome. Here is what I had

1:10 twist 22" savage barrel
180gr Sierra RN Pro Hunter
9.6gr Trailboss
Fed 210
2.810 OAL

Link Posted: 8/4/2007 4:18:00 PM EDT

Originally Posted By penguinland:
I worked some up and got to give them a go today. I had no stability problems and the sound, or lack of, was just awesome. Here is what I had

1:10 twist 22" savage barrel
180gr Sierra RN Pro Hunter
9.6gr Trailboss
Fed 210
2.810 OAL




Same load I developed about 2 yrs ago when I first heard about trailboss. The speer round nose work better though and you should also be able to bump you charge up about a grain or so and still stay subsonic. I know fro a fact my load withh easily kill deer out to 150 yds or go through a treated 4x4 at about 75 yds.
Link Posted: 8/5/2007 10:10:00 AM EDT
I got to shoot a couple with the can and they went through fine without any problem.
To clarify, with the gun zeroed at 100 yards with 168 federal GMM the EBR is 10 moa lower.
I emailed David of Shark suppressors before doing this and he said no problem.
Shooting EBR 180 grain thumper.
I was able to dig one up that I shot into Oklahoma red clay at point blank range.
I shot three but they went really deep, over 1 foot
No deformation except where it had clipped a small stone in the clay.
No expansion whatsoever. They may be made to expand in different material but at this point I am not a believer.
I didn't take any pics since nothing really happened, but I can snap one if anyone is interested.
In short, they are stable in my gun which is a FN SPR 1:12 twist. YMMV.
Link Posted: 8/5/2007 5:35:16 PM EDT

Not quite true. EBR has developed and patented a .308 projectile that does expand at subsonic velocities.

As I stated, no CONVENTIONAL rifle bullet will expand in any way. Those EBR bullets are far from conventional. They are very expensive specialty bullets.
Link Posted: 8/5/2007 7:47:23 PM EDT
.
Link Posted: 8/5/2007 8:03:45 PM EDT
I will have to play with some of the berry's I shoot sometime, I do not know how soft thier lead is but the plating is thin, and the flat point smacks the heck out of pop cans filled with water, I will have to try and come up with something thick enough to catch a bullet, the phone books here are not big enough.
Link Posted: 8/6/2007 5:40:03 PM EDT
[Last Edit: 8/6/2007 5:40:28 PM EDT by hi-tech-rancher]
Went to the ranch this weekend, but we were not able to get the subsonics loaded before the trip, because I had just gotten the bullets that same Friday. We did get to shoot a Friend's F/A Sturmgewehr, Reising, Delisle Carbine, and AK. What a blast!

However, we did manage to shoot a very large hog with my 6.8 SPC, loaded with Barnes TSX's. It only went about 40 yards.

Hope to shoot some of the 180 gr. Seirra Pro hunters soon.
Link Posted: 8/7/2007 7:57:53 AM EDT
I bought my Trailboss and 170 grain Sierra flat point 30-30 bullets. Can't wait to try it.
Link Posted: 8/8/2007 10:14:30 AM EDT
height=8
Originally Posted By PHD:
I do not know about the 200 gr Lapua bullets. I do know that the factory loaded Lapua 220 gr ammo is designed to stabilize in a 1:8 twist barrel at subsonic velocities and that is does not stabilize adequately in a slower twist.

Subsonic rifle cartridges are really tricky, and I do not load them. Instead, I buy from a commercial source, such as EBR, ES, or TTI. If you do not have quite enough powder charge to expand the case neck and obturate the chamber, you will get gas leaking back around the case rather than pushing the bullet out. This is a recipe for a stuck bullet just beyond the forcing cone.

Considering calculated kinetic energies, I would prefer a 147 (or 158) gr 9mm to any subsonic .223, and the KE of a subsonic .308 is not that much better than the heavy 9.


You have to use brass that is once fired in you riffle and only neck sized ,,that way you dont get gas leaking
Link Posted: 8/8/2007 10:22:00 AM EDT
height=8
Originally Posted By Green0:
I had heard this:

Boat-tails are a hindrance below the speed of sound, as they will yaw 180 degrees in order to fly BASE first. That 180 degree phenomenon can cost some accuracy.

The round nose, flat based ammo will not.


I figured that would be why TTI and EBR use the round nose ammo. That and the obvious fact the round nose ammo often is expanding ammo.

Hinelines experience seems to contradict that so maybe that's innaccurate?


The whisper uses 240gr match kings (boattail)
they dont go backwards until AFTER hitting a soft target ,ps that s whats its all about they dont expand but tumbles thus creating a large wound (inside)

The reason for round noses is that you can make a heavier bullet shorter if its a round nose versus boattail
Link Posted: 8/9/2007 8:40:18 AM EDT
Couldn't you seat a bullet backwards to increase the stability? Something like a FMJ-BT seated backwards would probably be very stable at SS velocities. One with a longer bearing surface, like Hornady, might be a good choice to ensure concentriciy and a secure seat in the case mouth.
Link Posted: 8/9/2007 5:30:40 PM EDT

Originally Posted By manowar669:
Couldn't you seat a bullet backwards to increase the stability? Something like a FMJ-BT seated backwards would probably be very stable at SS velocities. One with a longer bearing surface, like Hornady, might be a good choice to ensure concentriciy and a secure seat in the case mouth.


During World War II the Finns turned some of their subsonic rifle bullets backwards for better accuracy and improved terminal performance.
Link Posted: 8/9/2007 7:06:49 PM EDT

Originally Posted By 1UP5DN:

Not quite true. EBR has developed and patented a .308 projectile that does expand at subsonic velocities.

As I stated, no CONVENTIONAL rifle bullet will expand in any way. Those EBR bullets are far from conventional. They are very expensive specialty bullets.


Uh, nothing gets more traditional than a cast bullet. It is quite possible to get a cast bullet like a Lyman 311291 cast out of 2% Sn - 98% Pb to expand at 900 ft/s.

You could also go for some of the hollow point designs as well---these will expand at lower velocities and harder alloys. Just avoid using too hard an alloy like linotype as these are rather brittle and tend to have the nose shatter. Eletroype is a good alloy for such applications. Lyman #2 might be a bit brittle for hollow points, and possibly too hard for reliable expansion at low velocities w/out a hollow-point. (Lyman #2 is 2%Sn-6%Sb-92%Pb) [Sn=Tin, Sb=Antimony, Pb=Lead].

I've had good results with cast bullets as heavy as 225 gr in a 1 in 10 inch twist. Slower bullets need a bit less twist-rate to stabilize than ones that are moving at mach 2 or better.

Link Posted: 8/10/2007 9:33:52 PM EDT

Couldn't you seat a bullet backwards to increase the stability? Something like a FMJ-BT seated backwards would probably be very stable at SS velocities. One with a longer bearing surface, like Hornady, might be a good choice to ensure concentriciy and a secure seat in the case mouth.

Yes you can but trying to get any serious accuracy out of such a projectile is like trying to get blood out of a stone.

What is THE most important part of a bullet wrt accuracy? Well ask the benchrest guys and you'll discover it is the base. The flatter and more concentric the base of the bullet is the more accurate it is likely to be.

A HPBT bullet turned backwards is about as far from a flat base as you can get. Sure they are stable but they just won't group no matter what you try.
Link Posted: 8/11/2007 5:53:03 AM EDT

Originally Posted By 1UP5DN:

Couldn't you seat a bullet backwards to increase the stability? Something like a FMJ-BT seated backwards would probably be very stable at SS velocities. One with a longer bearing surface, like Hornady, might be a good choice to ensure concentriciy and a secure seat in the case mouth.

Yes you can but trying to get any serious accuracy out of such a projectile is like trying to get blood out of a stone.

What is THE most important part of a bullet wrt accuracy? Well ask the benchrest guys and you'll discover it is the base. The flatter and more concentric the base of the bullet is the more accurate it is likely to be.

A HPBT bullet turned backwards is about as far from a flat base as you can get. Sure they are stable but they just won't group no matter what you try.



So, it seems like we keep coming back to the Sirra 180-grain roundnose. One other point about which I am concerned is the bullet construction quality, because, if it is not exceptional, this would raise the risk of a baffle strike, and I don't want that! With flat base bullets, even the slightest variation could cause "wobble" until the bullet "goes to sleep." If the bullet has a major defect, it will hit the can long before air resistance and spin stabilization allows it to return to a cetrifugally stable flight.

Sierra makes great bullets, so I am hopeful that this is not likely going to be a problem.
Link Posted: 8/14/2007 2:04:24 PM EDT
tag
Link Posted: 8/15/2007 11:07:53 AM EDT

Originally Posted By PHD:
I do not know about the 200 gr Lapua bullets. I do know that the factory loaded Lapua 220 gr ammo is designed to stabilize in a 1:8 twist barrel at subsonic velocities and that is does not stabilize adequately in a slower twist.

Subsonic rifle cartridges are really tricky, and I do not load them. Instead, I buy from a commercial source, such as EBR, ES, or TTI. If you do not have quite enough powder charge to expand the case neck and obturate the chamber, you will get gas leaking back around the case rather than pushing the bullet out. This is a recipe for a stuck bullet just beyond the forcing cone.

Considering calculated kinetic energies, I would prefer a 147 (or 158) gr 9mm to any subsonic .223, and the KE of a subsonic .308 is not that much better than the heavy 9.


I've fired alot of the Lapua 200gr subsonic bullets without any issues in a Savage 110FP (1/10 twist) with a SWR Omega 30. they seem to be very accurate at subsonic velocities.
Link Posted: 8/15/2007 4:04:58 PM EDT

Originally Posted By bp_968:

Originally Posted By PHD:
I do not know about the 200 gr Lapua bullets. I do know that the factory loaded Lapua 220 gr ammo is designed to stabilize in a 1:8 twist barrel at subsonic velocities and that is does not stabilize adequately in a slower twist.

Subsonic rifle cartridges are really tricky, and I do not load them. Instead, I buy from a commercial source, such as EBR, ES, or TTI. If you do not have quite enough powder charge to expand the case neck and obturate the chamber, you will get gas leaking back around the case rather than pushing the bullet out. This is a recipe for a stuck bullet just beyond the forcing cone.

Considering calculated kinetic energies, I would prefer a 147 (or 158) gr 9mm to any subsonic .223, and the KE of a subsonic .308 is not that much better than the heavy 9.


I 've fired alot of the Lapua 200gr subsonic bullets without any issues in a Savage 110FP (1/10 twist) with a SWR Omega 30. they seem to be very accurate at subsonic velocities.


Bp...

Are you using Trail Boss powder? What powder charge are you using?

I could certainly see that the 200 or 220 grain bullet would be carry more energy loaded to around 1050 FPS, than, say, a 180. I have a 1-10 barrel, but I have no experience whatsoever with bullets this heavy. The last thing I want is a bullet strike on the can, or a stuck barrel I am going to develop my own SS loads VERY carefully.

My Ruger 77/44 integrally suppressed rifle shoots 300 grain Hornady XTP's and when they hit a hog in the head, it sounds like you hit a plastic trash can with a baseball bat! When loaded to about 1035 FPS, the 300 grainers outdo just about any other subsonic load I know of.
Link Posted: 8/16/2007 6:26:08 AM EDT

Originally Posted By hi-tech-rancher:

Originally Posted By bp_968:

Originally Posted By PHD:
I do not know about the 200 gr Lapua bullets. I do know that the factory loaded Lapua 220 gr ammo is designed to stabilize in a 1:8 twist barrel at subsonic velocities and that is does not stabilize adequately in a slower twist.

Subsonic rifle cartridges are really tricky, and I do not load them. Instead, I buy from a commercial source, such as EBR, ES, or TTI. If you do not have quite enough powder charge to expand the case neck and obturate the chamber, you will get gas leaking back around the case rather than pushing the bullet out. This is a recipe for a stuck bullet just beyond the forcing cone.

Considering calculated kinetic energies, I would prefer a 147 (or 158) gr 9mm to any subsonic .223, and the KE of a subsonic .308 is not that much better than the heavy 9.


I 've fired alot of the Lapua 200gr subsonic bullets without any issues in a Savage 110FP (1/10 twist) with a SWR Omega 30. they seem to be very accurate at subsonic velocities.


Bp...

Are you using Trail Boss powder? What powder charge are you using?

I could certainly see that the 200 or 220 grain bullet would be carry more energy loaded to around 1050 FPS, than, say, a 180. I have a 1-10 barrel, but I have no experience whatsoever with bullets this heavy. The last thing I want is a bullet strike on the can, or a stuck barrel I am going to develop my own SS loads VERY carefully.

My Ruger 77/44 integrally suppressed rifle shoots 300 grain Hornady XTP's and when they hit a hog in the head, it sounds like you hit a plastic trash can with a baseball bat! When loaded to about 1035 FPS, the 300 grainers outdo just about any other subsonic load I know of.


Honestly, if I had a 77/44 I probably wouldn't waste my time with SS .308 loads. That said, yes I was using trailboss powder. I'd have to lookup the load I was using but it was between 9-11grains. The problem is slight varations in case volume and seating depth seem to have a HUGE effect on accuracy for SS .308 even using really nice ammo like the Lapua. The best I could do was around 2 MOA using SS loads. You could use a suppressed 9mm and do just as good. If you could wing them out to 300 yards and had a 1 MOA spread then it might be more useful.

If I try working up some more this year I'll probably order a package of Lapua brass ($$!) and measure case volume and try to see how close I can make each round in volume and seating depth.
Link Posted: 8/16/2007 10:38:12 AM EDT

Originally Posted By bp_968:

Originally Posted By hi-tech-rancher:

Originally Posted By bp_968:

Originally Posted By PHD:
I do not know about the 200 gr Lapua bullets. I do know that the factory loaded Lapua 220 gr ammo is designed to stabilize in a 1:8 twist barrel at subsonic velocities and that is does not stabilize adequately in a slower twist.

Subsonic rifle cartridges are really tricky, and I do not load them. Instead, I buy from a commercial source, such as EBR, ES, or TTI. If you do not have quite enough powder charge to expand the case neck and obturate the chamber, you will get gas leaking back around the case rather than pushing the bullet out. This is a recipe for a stuck bullet just beyond the forcing cone.

Considering calculated kinetic energies, I would prefer a 147 (or 158) gr 9mm to any subsonic .223, and the KE of a subsonic .308 is not that much better than the heavy 9.


I 've fired alot of the Lapua 200gr subsonic bullets without any issues in a Savage 110FP (1/10 twist) with a SWR Omega 30. they seem to be very accurate at subsonic velocities.


Bp...

Are you using Trail Boss powder? What powder charge are you using?

I could certainly see that the 200 or 220 grain bullet would be carry more energy loaded to around 1050 FPS, than, say, a 180. I have a 1-10 barrel, but I have no experience whatsoever with bullets this heavy. The last thing I want is a bullet strike on the can, or a stuck barrel I am going to develop my own SS loads VERY carefully.

My Ruger 77/44 integrally suppressed rifle shoots 300 grain Hornady XTP's and when they hit a hog in the head, it sounds like you hit a plastic trash can with a baseball bat! When loaded to about 1035 FPS, the 300 grainers outdo just about any other subsonic load I know of.


Honestly, if I had a 77/44 I probably wouldn't waste my time with SS .308 loads. That said, yes I was using trailboss powder. I'd have to lookup the load I was using but it was between 9-11grains. The problem is slight varations in case volume and seating depth seem to have a HUGE effect on accuracy for SS .308 even using really nice ammo like the Lapua. The best I could do was around 2 MOA using SS loads. You could use a suppressed 9mm and do just as good. If you could wing them out to 300 yards and had a 1 MOA spread then it might be more useful.

If I try working up some more this year I'll probably order a package of Lapua brass ($$!) and measure case volume and try to see how close I can make each round in volume and seating depth.



Thanks for your input. I tend to agree with you about the 77/44, but with the truncated cone bullet, the accuracy is just about 2" with it, anyway. I had hoped that using good, high-quality secant ogive bullets like the SMK might help, but the ss velocities just don't allow for the same bullet stability, so it may never get much better than 1.5 MOA

Not a problem, though. I bought the .308 because it is such an outstandingly accurate rifle which can be used for hunting deer and hogs, with full-power rounds, suppressed, and this blows away the 77/44, though it is a little louder with the supersonic crack. That is still minimal when you consider the utility, and the hearing safe sound levels.

Subsonic is really just a novelty with the .308, but then again, I think shooting should be fun!
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