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rxer311
6 August 2018, 15:40
Sorry if this is long winded but I do have a picture at the end that may help explain what I am trying to do. Essentially I am trying to use a larger diameter rail to get as much real estate as possible on a short barrel rifle. My suppressor will be recessed in the rail. What I am trying to determine is whether it would be safe to fire without the silencer and only the FH. I have provided some measurements.

Trying to plan out a 300 blk build (my first). It will be suppressed with a Saker 7.62 with MAAD mount.

I am thinking about designing this build around a Ballistic Advantage 8.3" Performance Series barrel with pinned GB. I am building this off of an Aero M4E1 set. I am going to use a Gen 2 Mlok rail which is actually 9.22" (rounding to 9.25" for my purposes. I am going to allow for 0.5" of threading at the end of the barrel so the shoulder of the barrel where it will meet my saker FH would be recessed 1.45". From the shoulder of the barrel to where the prongs open up on the FH it is 1.25". This leaves the FH prongs starting to open up 0.2" inside the rail.

So would this be safe to fire?

I know that I could just purchase the Maad mount blast shield but that at $145 and another $200 for another MAAD mount is another $350 to a build that seems senseless when it would be fired suppressed 95% of the time.

https://i.imgur.com/qVEo2KC.jpg

alamo5000
6 August 2018, 16:07
Sorry if this is long winded


You had me at long winded! LOL!

(see guys! I'm not the only one!)

rxer311
6 August 2018, 16:24
Gotta get all the info in.

alamo5000
6 August 2018, 16:30
Sorry if this is long winded but I do have a picture at the end that may help explain what I am trying to do. Essentially I am trying to use a larger diameter rail to get as much real estate as possible on a short barrel rifle. My suppressor will be recessed in the rail. What I am trying to determine is whether it would be safe to fire without the silencer and only the FH. I have provided some measurements.

Trying to plan out a 300 blk build (my first). It will be suppressed with a Saker 7.62 with MAAD mount.

I am thinking about designing this build around a Ballistic Advantage 8.3" Performance Series barrel with pinned GB. I am building this off of an Aero M4E1 set. I am going to use a Gen 2 Mlok rail which is actually 9.22" (rounding to 9.25" for my purposes. I am going to allow for 0.5" of threading at the end of the barrel so the shoulder of the barrel where it will meet my saker FH would be recessed 1.45". From the shoulder of the barrel to where the prongs open up on the FH it is 1.25". This leaves the FH prongs starting to open up 0.2" inside the rail.

So would this be safe to fire?

I know that I could just purchase the Maad mount blast shield but that at $145 and another $200 for another MAAD mount is another $350 to a build that seems senseless when it would be fired suppressed 95% of the time.



What is the ID of the rail?

I am not that familiar with MAAD mounts but how much over the shoulder do they mount?

Another point is I think your math is off. I have done the math to get a tight squeeze more than once. Barrel length minus .7 (or .8) equals the length of a really good fitting suppressor. That said my cans do not overlap the barrel shoulder.

If your barrel is 8.3 then you minus .7 that would be a 7.6 inch rail that would give you a fit very near the shoulder.

The rail is 9.22 inches and the threading is typically as far as I know is a little more than 1/2 inch. Say .7 inches from the shoulder to the absolute crown. It might be .5 inches. I don't know for sure.

From the way I am figuring it the absolute end of the muzzle will be .92 inches to 1 inch from the end of the hand guard.

Then a muzzle device will add some extra length from the crown of the barrel before it starts with whatever geometry it uses. My Griffin mini flash hiders add about 1/4 of an inch before it opens up. .92-.25=.67 inches that you will potentially have muzzle blast hitting the end of your hand guard.

I don't think that will be too big of a deal, but that MAAD mount seems to have a collar on it and the flash hider is kind of long so in theory with just the flash hider it could get you a lot closer to the end of the rail.

It seems to me like your plan will recess the can just enough to be a royal pain in the ass to get it on or off.

alamo5000
6 August 2018, 16:37
Gotta get all the info in.

They give me grief so I am making some self deprecating humor. [:D]

rxer311
6 August 2018, 16:57
What is the ID of the rail?

I am not that familiar with MAAD mounts but how much over the shoulder do they mount?

Another point is I think your math is off. I have done the math to get a tight squeeze more than once. Barrel length minus .7 (or .8) equals the length of a really good fitting suppressor. That said my cans do not overlap the barrel shoulder.

If your barrel is 8.3 then you minus .7 that would be a 7.6 inch rail that would give you a fit very near the shoulder.

The rail is 9.22 inches and the threading is typically as far as I know is a little more than 1/2 inch. Say .7 inches from the shoulder to the absolute crown. It might be .5 inches. I don't know for sure.

From the way I am figuring it the absolute end of the muzzle will be .92 inches to 1 inch from the end of the hand guard.

Then a muzzle device will add some extra length from the crown of the barrel before it starts with whatever geometry it uses. My Griffin mini flash hiders add about 1/4 of an inch before it opens up. .92-.25=.67 inches that you will potentially have muzzle blast hitting the end of your hand guard.

I don't think that will be too big of a deal, but that MAAD mount seems to have a collar on it and the flash hider is kind of long so in theory with just the flash hider it could get you a lot closer to the end of the rail.

It seems to me like your plan will recess the can just enough to be a royal pain in the ass to get it on or off.

Your last point was also a secondary concern of mine. I don't want it to be too much of a pain in the ass.

rxer311
6 August 2018, 16:59
So my options would be to do a 9" barrel or a 7" rail...

alamo5000
6 August 2018, 17:29
So my options would be to do a 9" barrel or a 7" rail...

I have a 9" barrel on mine with an SLR 8.3" rail and the fit is near perfect.

I am not going to lie and pretend that I know about Silencerco stuff when I don't. I need to see how that thing mounts.
----

OK, I watched this video and I think that's the mount you are talking about right?


https://www.youtube.com/watch?v=SrfRxhg8_9w

From the looks of that you won't have too much trouble but the only part that will be recessed might be that knurled ring and maybe a little bit more or less.

In this screen shot it looks like that mount (if it's the right one) doesn't sit right on the shoulder like my Griffin ones do. Again I am not certain if this is the type of mount you will use.

5689

If it is you will probably be able to get away with a slightly longer handguard than normal, ie possibly an 8.5" barrel and a 8" handguard or something like that. 9" handguard, 9.5 barrel etc etc. I don't know how much that mount rises from the shoulder so other people who own those will have to vouch. Those wrench flat risers need to be measured.

UWone77
6 August 2018, 17:51
If any of the gasses look like they'll escape into the handguard, I wouldn't do it.

rxer311
6 August 2018, 17:51
That is the mount.

alamo5000
6 August 2018, 18:05
If any of the gasses look like they'll escape into the handguard, I wouldn't do it.

Same thought here. If it's suppressed then ok, whatever, but unsuppressed, I wouldn't do it.


That is the mount.

If that's the mount then find someone who has that mount or call Silencerco and ask them how tall (from the barrel shoulder) those wrench flats are. I would be willing to bet they are at least 1/4 of an inch, and if so you could probably get away with doing a -.5 inches from your barrel length to get your hand guard length. It wouldn't even need to be recessed at all then, thus solving all problems.

The number you are actually looking for is how far it is from the shoulder of the barrel to the base of the can when it's fully mounted. Anything more than .2 inches and you are good to go.

Another thing I am learning about 300 BLK is that an adjustable gas block is absolutely priceless for that caliber. On other guns, meh, it's ok, but the value of an adjustable block on 300 BLK goes up fast, especially if you reload and want to experiment with a variety of load data.

rxer311
6 August 2018, 18:25
I agree that this idea is scrapped. Going to do either an all 7.5" or Troy socc 7.6".

UWone77
6 August 2018, 18:27
I've got an 8" 300 Aero/Ballistic Advantage barrel on a 7" CMT Handguard, but with the Dead Air mount. Not recessed, but close to the handguard as I could get it for an 8"

alamo5000
6 August 2018, 18:37
I've got an 8" 300 Aero/Ballistic Advantage barrel on a 7" CMT Handguard, but with the Dead Air mount. Not recessed, but close to the handguard as I could get it for an 8"

Can you put a pic up here of the gap and possibly measure it for us?

Joelski
6 August 2018, 20:08
Another thing I am learning about 300 BLK is that an adjustable gas block is absolutely priceless for that caliber. On other guns, meh, it's ok, but the value of an adjustable block on 300 BLK goes up fast, especially if you reload and want to experiment with a variety of load data.

Opposite. I find that my 300 goes from can to not, sub to super without a hint of trouble. No special springs, simple Carb buffer, nothing. Maybe that's the beauty of the 10.5" barrel, I don't care. I'm leaving it alone and counting my blessings.

I'm not obsessive about my gap either. I think it looks good and I don't need welding gloves to shoot. [:)]https://uploads.tapatalk-cdn.com/20180807/3a71f428e30b8ff06ae5221403e96058.jpg

alamo5000
6 August 2018, 20:36
Opposite. I find that my 300 goes from can to not, sub to super without a hint of trouble. No special springs, simple Carb buffer, nothing. Maybe that's the beauty of the 10.5" barrel, I don't care. I'm leaving it alone and counting my blessings.

I'm not obsessive about my gap either. I think it looks good and I don't need welding gloves to shoot.

I am brand new to 300 BLK but I have to admit that I am taking all the oddball approaches possible to getting various loads out there. So far I have to say that I've had some pretty good success with a wide array of powders, stuff that normally wouldn't be used in a rifle. And they are super clean as well.

I really do wish I had a sound meter. I could geek out like nobody's business at least for a while. If the Silencer Shop guys show up on the forum again maybe they will let me show up one day and I can do a controlled ammo test.

I would be able to really see if there is a difference and how much difference between different ammo. I made a couple of loads that were just stupid quiet. Some of them wouldn't cycle the action until I changed gas settings. It's definitely keeping my attention in the reloading realm.

UWone77
7 August 2018, 21:30
5692

Joelski
8 August 2018, 04:35
Mind the gap, ladies. [:D]https://uploads.tapatalk-cdn.com/20180808/7c10c3623b72bcf010c3ea977d398783.jpeg

mustangfreek
13 August 2018, 00:48
Chive on :P


Its close, hard to tell/know how much pressure/blast is right there

Well solution #1

Shoot it suppressed 100% of the time instead of 95

Or...

They make an 8.5” barrel as some other good places

[:D][BD]