Suppressors Installation of Surefire Socom SFMB-762-5/8-24 on P-308

[TexasGunTrustLawyer]

Just picked up a new POF P-308.

I am planning on running a Socom 762 on it.

Installed the SFMB-762-5/8-24 brake-mount on the rifle.

Some observations:

1. This isn't the first MB that I have installed. I have had similar fun with the AAC 51 tooth brakes and other surefire brakes.
2. I must be doing something wrong. The Ever-So-Helpful clock diagram included witht eh instructions never seems to give me the right combination
3. It is fun trying all the different color combinations on the washers until you get just the right combination and the mount times perfectly with about the right amount of force.
4. The feeling of satisfction with #3 occurs is only equaled by the feeling of relief that the mount really will time properly with the shims they included.
5. Waiting 24hrs for the rockset to cure sucks.
6. Seeing the suppressor mounted correctly onthe rifle's muzzle is a great feeling . . . . it will be even better when I shoot it!

The photos are posted on my www.TexasGunTrust.com Facebook page.

 

[MSTN]

The SF timing diagram gives you a generally accurate idea of how many degrees prior to perfect alignment the muzzle device should bottom out on the shims when hand tightening in order for you to arrive at the correct torque value.

Here's the only rub: The rate of the torque build up is totally dependent on the thickness of the stack of shims you're using. It's very quick, abrupt, sudden, with a thin stack of shims, and much more gradual with thicker stack.

With a tall stack of shims needed to compensate for a rotational correction, the torque builds smoothly and the SF timing diagram works just fine.

But, with just one or two shims needed for a small correction, the torque build up is quite abrupt. If you're lucky, it's perfect. If it's not, your only alternatives are 0.001" shim stack adjustments or adding a full thread's worth of shims (0.42") and starting over. Sometimes the simplest thing is to go to a second SF muzzle device with different thread timing.

Take care not to over-torque! Err to the lighter side, if required.

 

[TexasGunTrustLawyer]

Agreed. I noticed the washers did not end up even.

If it is over torqued, I was told that it compresses the crown and affects bullet flight/impact

 

[KYS]

I think the rock set application is over hyped. If you are correctly timing these brakes and applying the appropriate amount of force to your wrench, there should be no reason for it to back off during fire. Especially on a precision rifle, the course of fire never gets that heavy.

 

[MSTN]

Agreed. I noticed the washers did not end up even.

If it is over torqued, I was told that it compresses the crown and affects bullet flight/impact

None other than Barry Duecke of SF told me the same thing about over-torquing. He demonstrated that to his own satisfaction with a set of pin gauges.

The shims certainly are not self-centering, especially the thin ones which seem to want to catch on the threads. Before you bring up the torque on the muzzle device, just use your thumb and forefinger to center up the shims on the barrel. Then, smoothly screw the muzzle device down and make initial contact, holding the shims in that position.

 

[MSTN]

I think the rock set application is over hyped. If you are correctly timing these brakes and applying the appropriate amount of force to your wrench, there should be no reason for it to back off during fire. Especially on a precision rifle, the course of fire never gets that heavy.

I don't use Rocksett on my own muzzle devices, but I'm not headed to combat. I'm always taking uppers apart, swapping things around, trying different suppressors, etc. My suppressors sometimes get plenty hot, especially on the SBR's. I remove the suppressor while still warm, if possible, but even after cool down I have never experienced the slightest problem. But, I do try to keep the mating surfaces clean, which makes a difference, I'm sure.

Rocksett applied properly makes it extremely tough to remove a muzzle device. Soaking the muzzle upside down in water is the only way I know to do it, IF the Rocksett was properly applied.

But, Rocksett requires scrupulously clean mating surfaces. Without that, it holds no better than Blue Locktite. Sounds like glass crunching when you remove the muzzle device.

 

[TexasGunTrustLawyer]

MSTN . . Information was received from Garin at surefire.

 

[MSTN]

Garin always has the gouge.

 

[TexasGunTrustLawyer]

I think the rock set application is over hyped. If you are correctly timing these brakes and applying the appropriate amount of force to your wrench, there should be no reason for it to back off during fire. Especially on a precision rifle, the course of fire never gets that heavy.

Te last thing you ever want to have happen is a surefire mount to come off the rifle in the can . . . LOL

 

[KYS]

Te last thing you ever want to have happen is a surefire mount to come off the rifle in the can . . . LOL

If you neglect checking your muzzle device long enough to let it unscrew and fall off with your suppressor attached then you DESERVE the suffering of getting it off!!!!

 

[TexasGunTrustLawyer]

If you neglect checking your muzzle device long enough to let it unscrew and fall off with your suppressor attached then you DESERVE the suffering of getting it off!!!!

Well . . . There is that also. I have to agree.