• If you enjoy the forum please consider supporting it by signing up for a NES Membership  The benefits pay for the membership many times over.

SBR Question

EddieCoyle

Consigliere
Moderator
NES Member
Joined
Nov 11, 2005
Messages
21,328
Likes
9,786
Location
Northern, MA
Feedback: 160 / 0 / 0
Don't read too much into this, but have any of you ever seen or heard of someone making a SBR AR in .458 SOCOM?
 
I met a guy at SHOT who appeared to be the authority on .458 Socom.

He had uppers, custom ammo, and even cans, all optimized for .458 Socom. I'll see if I can find his card.

My buddy built a TC Encore in .458. He bought some very very heavy .458 loads (I'm thinking 400 gr) that were subsonic. They were pretty quiet considering the .45" exit aperture on the can.

Don
 
i think it's a fantastic idea. i'd looked at the tromix stuff but then realized that even if i scraped together the cash to build it... i wouldn't be able to feed it.
 
I met a guy at SHOT who appeared to be the authority on .458 Socom.

He had uppers, custom ammo, and even cans, all optimized for .458 Socom. I'll see if I can find his card.

My buddy built a TC Encore in .458. He bought some very very heavy .458 loads (I'm thinking 400 gr) that were subsonic. They were pretty quiet considering the .45" exit aperture on the can.

Don

Can you run subsonic 458SOCOM through a 45 can?
 
it depends on what kind of bullet you intend to shoot through it.

Its all about pressure and volume of gas.

If you intend to shoot a 250 gr bullet at 900 fps, then you should be fine, as this is effectively a .45 Super.

If you intend to run the cartridge at anything near full performance (whether its a 250 gr bullet at 1800 fps or a 500 gr bullet at 900 fps), you are generating much too much pressure and gas volume for a .45 ACP can to deal with effetively.

Even if you were to make a .45 ACP can capable of taking the pressure, its volume would not be substantial enough to effectively silence the round given the large volume of gas a full pressure (whether fast and light or slow and heavy) round would create.

I have a thing for .22 cans because they are the only handgun cans that don't destroy the balance of the gun, with one exception.
I have the only 9mm can that I know of that is light enough to work without a piston and doesn't destroy the balance of the gun.

Its called the DeGroat Nano. Its all titanium and is sized like a .22 can. It also weighs only 3 ounces, about like a .22 can. But this extreme smallness has required other engineering compromises. It uses an end wipe. Its a piece of plastic that is pierced by the bullet and effectively closes the exit aperture after the bullet leaves the can.

This allows a small can to retain more gas and decreases noise. But it also allows a lot of pressure to remain in the can at the time the slide begins to come back. When this happens, the handgun blows a lot of gas and crap out the ejection port, which makes a mess and is just plain annoying. But its small and reasonably quiet.

If you remove the wipe, or drill a hole in it, the can gets much much louder because the volume is not large enough to work with 9mm's volume of gas without a wipe.
It also works just fine as a .22 can without wipes because of the .22's lower powder volume. With a .22 sized hole drilled in the wipe, it works great as a .22 can.

I like it because with a drilled wipe, it works pretty wall as a full auto rated .22 can.
With a standard wipe, its a moderately effective 9mm can that doesn't ruin the balance of the gun.

Don
 
Last edited:
Can you run subsonic 458SOCOM through a 45 can?

that's a damn good question. i looked at a few models and it seems like the answer is "it depends". this one says .45 ACP, .450 bushmaster, .44 magnum, and .458 socom are all OK: http://www.coastalgun.com/Home/Suppressors/CenterFireRifleSupressors/ModelXSuppressor.aspx

someone posted in a thread elsewhere:

A 458 SOCOM suppressor that would work for subsonic and supersonic is probably the best choice. I'm not selling anything, so the info below is just the facts as I see them.

Using the Quickload program to simulate your scenario....

10" barrel, 25.4gr RL-7
500gr bullet, chamber pressure-- ~25,000psi, muzzle pressure-- ~4715psi
300gr bullet, chamber ~10,000psi, muzzle ~3416psi

16" barrel, 25.4gr RL-7
500gr bullet, muzzle ~2823psi
300gr bullet, muzzle ~2216psi

Conclusion:
A commercial 45 ACP suppressor is made to operate in the muzzle pressure range of 2500-5500psi based on the muzzle pressures for a 4-5" barrel handgun. A 458 SOCOM commercial suppressor that can handle subsonic and supersonic would be built for a muzzle pressure range up to 10,000psi (or maybe 12,000psi).

Therefore, a commercial 45 ACP handgun suppressor on a 458 SOCOM (subsonic only) with either a 10" barrel or 16" barrel operates within the muzzle pressure of the suppressor design. Subsonic only should pose no danger at all to the suppressor.

The powder is burned in the barrel, so the argument of more powder or higher pressure because it is a rifle is a false belief/statement. The muzzle pressure is what counts in regards to a suppressor.

That said, the Quickload program shows that Reloder 7 only has about 85% of propellant burned in a 10" barrel with a 500gr bullet; and 55% of propellant burned in 10" barrel with a 300gr bullet. It would seem to me that a faster burning powder is more appropriate to get 100% burn in the barrel. Even with a 16" barrel, the simulation for Reloder 7 shows 89% burn for 500gr bullet and 62% for a 300gr bullet. I suggest something slightly faster like Hodgdon H110 (or VV N110) since it has a 94% burn in a 10% barrel for a 500gr bullet (62.6% case fill, where ~22gr should give you about the same subsonic velocity as 25.4gr of Reloder-7). VV N110 is slightly faster than H110 and for the same 500gr bullet at subsonic velocity, it gives a 99% burn rate in 10" barrel (~19.5gr of VV N110 with 72% fill, should give the same velocity as ~22gr of H110 or 25.4gr of RL-7).

I use VV N110 for 338 Federal subsonic using 300gr bullets and that powder works very well. It's a stick powder.
 
Last edited:
If someone builds a .45 ACP can that can take a full pressure .458 Socom, then its by engineering necessity larger and heavier than is optimal for a pure .45 ACP can.

You can't change the laws of physics. There is no free lunch.

For example, Gemtech makes a 5.5 ounce .45 can. (plus the weight of the mount).

Compare that to a .458 can that can take full pressure loads at well over a pound even if its made of Ti.
The gemtech is not made of anything exotic, just 7075 Al
 
Last edited:
Back
Top Bottom