From what I've read the .458 Socom was designed to work subsonic, thus suppressed. Reading another thread here, I see one Socom owner says his is still relatively loud, even suppressed.

I would like to read other's exeperience with this cartridge suppressed. Does suppression work well or not? Is the bore too big for significant noise reduction?

For example, I know they suppress the 50 BMG, but I don't know to what effect.

Thanks,
KB

asking Ranb if his socom loads were subsonic?

I have had much drama over my 458 socom AR-15, most of it due to my inexperience. I bought a Tromix barrel on a RRA upper a few years back. I tested it with supersonic 405 grain jacketed bullets and subsonic (with 20 grains WC820) 535 grain cast bullets. The cast bullets cycled the action properly but I had to use a cut down spring and empty buffer to make the cast subsonic loads work properly.

Then I made my first mistake. I removed the barrel and turned it down to better accept a two point mounted silencer I was making for it. When I reassembled it, I noticed that the subsonic cast loads were no longer extracting and not feeding very well either. I also noticed that the brass was coming out very dirty. Better cleaning and proper brass sizing improved but did not eliminate the problem. After discussing this with Marty on and off for a while, I tried slower powders which helped, but I still had problems until I realized I had re-attached the front sight 0.025" forward of the correct position on the barrel, further restricting gas flow to the gas tube. Fixing this big mistake resolved all of the problems; almost.

I currently use AA #7 for most of my loads. This powder is slower than WC820 or H110 and makes for better extraction. I am happy with the upper for the most part now.

The homemade silencer is another issue. The bore is a bit over half an inch and lets out lots of noise. It has only been shot suppressed a few times and I think it is rather loud. I am thinking about taking it with on my Vegas vacation and may take some video of it then.

Ranb

Seems very complex, working out all the bugs in the feeding and ejection of the load/rifle combo. Too complex for me, so the probability of me going there (with AR platform) is slim.

Instead, hopefully I've bypassed most all that with a bolt action 458, which feeds, and ejects just fine, subsonic or not.

So, the question remains about suppressing subsonic 458 loads, using 405 gr FN bullets and 21 grs of Trail Boss, for example, at 1050 - 1070 fps muzzel? The combo could be 350 gr bullets and 20grs of TB, or whatever charge yields subsonic vel. That's simple, a cronograph will solve that riddle.

It could cost a lot to experiment with these suppressors, unless a guy has the shop and tools and skill to do it himself. That's why I would like to know in advance if it will work, and just how well or not so well. Seems to me the principles of suppression are the same, whether using a 22 or 458. Since I'm talking subsonic, then speed isn't a variable factor, just bullet diameter, and gas volumn. Is it a matter of simply a bigger can, or something else?

KB

Do not make the mistakes I made, and it should not be a problem. Who is making your 458 bolt gun? I want to re-barrel a savage to 458 socom and can not find anyone to chamber a barrel for me.

As for the silencer, anything burning 20-30 grains of powder and having a silencer with a half inch bore needs plenty of volume and length ahead of the muzzle. I think if I had 10" out in front of the muzzle and better baffles, it would be much nicer, especially on a bolt gun.

I limit my loads to 1050 fps. My next few projects (22lr, 223) will be with step cone baffles. They are supposed to make for more turbulence inside and better suppression. I can post a few drawings if you are interested.

I thought it was easy to learn how to use a lathe while making my first silencer. I have learned more about design than actually operating a lathe in the last several years.

Ranb

quote:

Originally posted by ranb40:
Who is making your 458 bolt gun? I want to re-barrel a savage to 458 socom and can not find anyone to chamber a barrel for me.
Ranb

http://forums.accuratereloadin...4711043/m/1101023231

I'm relatively sure Pac-Nor will chamber a barrel for you, but as I have done in the past, I bought the reamer, and let them use it on their barrel. Some of those reamers I still have, and some I sold and got most of the cost back.

I thought about a bolt action 458 Socom, but I'm real particular about feeding. Finding a bolt action that would feed was a deal breaker for me, for the Socom. There are several issues to overcome - one is I don't like detachable magazines, also getting brass. Plus the Socom is a bit single purpose for me.

As I said, I tried the 450 Marlin cartridge in a bolt action and that didn't work out - feeding issues. The 458 WM solved a multitude if issues at once, and didn't create any that wouldn't be present in the Socom - that I can think of.

PacNor was very cooporative in helping with the short throat chamber. This is basically a 458WM with a 45-70 throat, rather than the standard SAAMI long throat 458. It's stamped short throat right on the barrel.

My platform is good as far as I can tell, so far. I'll be testing a lot more before deciding about a suppressor. But it's a candidate.

KB

Pac-Nor told me they would make me a barrel if I supplied the 458 reamer, but I can not find a reamer to rent or buy. The last time I looked was over a year ago though.

Ranb

quote:

Originally posted by ranb40:
Pac-Nor told me they would make me a barrel if I supplied the 458 reamer, but I can not find a reamer to rent or buy.
Ranb

Call PTG: http://www.pacifictoolandgauge.../reamers/chamber.htm

quote:

Originally posted by Kabluewy:
I thought about a bolt action 458 Socom, but I'm real particular about feeding. Finding a bolt action that would feed was a deal breaker for me, for the Socom.

Not a terribly difficult issue to resolve (or the barrel either for that matter):

http://www.youtube.com/watch?v=WsYyfQrzo2I

That video is interesting. Seems to feed well. I wonder if that's a detachable magazine? It looks like the cartridges are single stack. I also wonder if the bolt will close over three cartridges down?

I've been testing my 458WM, and it working out alright. Some little things to deal with. I had Warne rings, and if I used all the eye relief by pushing the scope nearly as far forward as it would go, the rings somehow put the scope in a bind, and I couldn't turn the variable magnification adjustment ring. today the new Leupold rings came in, and I put them on the rifle right away. They work much better, and lower too, and no issues adjusting the power of the scope from 1x to 4x. I managed to get another 1/4" of eye relief. Every little bit counts, since it's almost got me a few times.

The main thing that's a relief is that there are no feeding issues.

I tested the trail boss loads, and they were not accurate. I tested some with SR 4759, and they are a lot more accurate, but I haven't tried any 4759 loads subsonic, yet.

For now at least, I've settled on a more powerful load, with 350gr bullets at about 2150 fps. It is accurate, but kicks a lot. I'm getting used to it.

KB

quote:

Originally posted by Kabluewy:
I wonder if that's a detachable magazine?

Nope, internal - late centerfeed action.

quote:

Originally posted by Kabluewy:
It looks like the cartridges are single stack.
I also wonder if the bolt will close over three cartridges down?

They are double stacked under the top one in the magazine box.

Three down, although the magazine well had to be inletted about .100" deeper to do it.

quote:

Originally posted by ranb40:
Pac-Nor told me they would make me a barrel if I supplied the 458 reamer, but I can not find a reamer to rent or buy. The last time I looked was over a year ago though.

Ranb

If you check with Marty, there's a gun shop in Conroe TX that chambers for the SOCOM and would probably make a Savage barrel.

I had them re-barrel a Remingtom 700 EtronX in 458 SOCOM for the express purpose of suppressing it but haven't got around to the supressor yet.

With no firing pin to fall, it should be plenty quiet. You're correct about the amount of chamber in front of the muzzle; with a hole almost a half inch in diameter the path of least resistance for gas is down the supressor bore and you need "time" for the gas to disperse laterally.

A google seach gives me about seven gun shops in Conroe, TX. Can you give me the name of it? Thanks.

Ranb

I tried to search too; I think it was "Sportsman's" something or other. You can email Marty on his website (teppojutsu.com) and find the right place.