Reloading With A Suppressor

[cohunt]

most of my suppressed AR rifles are only open 1 to 2 full turns, so that would be reducing the gas port size down to 25-50%--I run suppressed on 3 different lengths of 223, 3 lengths of 6.8, and a pistol 300bo and 16" 308w--I have sub loads for both the 308 and 300bo--the only one I dont run an adjustable GB on is the 10.5" 300bo with pistol gas--all the others require an adj gas block to get the gas pressure just right---it also depends on who manufactured the barrel and if they know what the proper size gas port is or just do a "quick and dirty- larger than needed" so it cycles on anyone's gun-- lots of guys run super heavy buffers, this is a band-aid to just getting the right amount of gas

 

[Farmerboy78]

So, I use a superlative bleeding gas block, you set it for a non suppressor time, and it will vent the extra gas caused by the suppressor.

 

[cohunt]

So, I use a superlative bleeding gas block, you set it for a non suppressor time, and it will vent the extra gas caused by the suppressor.

Ive never understood that design-- why would you want to vent "extra gas"? there isnt such a thing as extra gas-- keep it in the barrel to help push the bullet -- I also know when they first came out with the design that no matter what position it was in, it was still overgassed with a 6.8spc-- I think they enlarged the "vent port" on them since then though

 

[John Klingenberg]

I dont recall off the top of my head how many bolt guns I have but I do know how many I have that are threaded!

One...6.5-06 that I built for my wife that I h the barrel threaded for a brake. I know my M1A is threaded but I've never tried to remove the flash hider.

I have one more suppressor coming and it will go on this 6.5 Grendel permanently. The can on it now will go back on my 7.62x39 AR that is crazy accurate!

cohunt,
Thanks for all that detailed info!

I am well known on the 6.5 Grendel forum as a hater of short barreled 6.5 Grendel's. Its was certainly not designed to be shot from such short barrels, but I built this one to reduce the weight for my wife. Maximum range it will be shot in a hunting situation would be 150 yards so the velocity loss is not a big deal.

My wife hates the pistol brace so I already submitted a Form 1 so I can put a normal AR stock on it. It's still not as light as I had hoped.

It is a pistol gas system...I wish it had been a carbine length. I could have used the Osprey piston system on it that I had.

Getting ready to tear it down now and install the adjustable gas block.

I always thought the grendel as ho hum in my AR up to 20". Then I put together a 26" on a savage. What a difference. Shooting 100gr A-Max or ELD I get 2980fps. Puts it in a whole other class of mouse gun.

 

[azarcher10x]

Ive never understood that design-- why would you want to vent "extra gas"? there isnt such a thing as extra gas-- keep it in the barrel to help push the bullet -- I also know when they first came out with the design that no matter what position it was in, it was still overgassed with a 6.8spc-- I think they enlarged the "vent port" on them since then though

I used the Superlative on my suppressed AR and I couldn't use the vent setting. Even wide open, it wouldn't vent enough to work. Ended up only 25% open on restriction. Of course the varmint load is 3700 fps!

 

[Okanogan]

The can will radicalize your ES. Especially if you remove and put it back on often. It's best to just leave it on one gun. ARs ,in my experience, are not the best host for cans unless you tune them and leave it be.

My experience has been different. I have had no issues swapping back and for between AR platforms. For me the Ultra 7 with a CB brake has returned to POI after remounting the suppressor. Also the favored loads for each rifle have not had any more noticeable change in ballistics than I tend to see with my unsuppressed bolt guns over time. I'm using SLA gas blocks on the 6.8 SPC & .224 Valkyrie and each rifle has its own CB brake that doesn't get removed. Granted, I don't swap the uppers around on the lowers much because the buffer springs differ and I don't mess with the adjustable gas block settings very often. I'm not disagreeing that others may have had a different experience. I do think that doing the load development for each platform with the suppressor installed is probably a good practice rather than developing the load without the suppressor and expecting similar performance after the suppressor is installed.

My only real complaint about running the ARs suppressed is the additional fouling that occurs but even that tends to vary for me depending on the powder and platform. My Valkyrie with CFE 223 is terrible for fouling, to the point that the SLA adjustable gas block on it is noticeably stiffer to turn than the others.

 

[CaptnC]

I'm so used to using my Magnetospeed during load development that I feel lost without, especially on the AR platform.

This being my first short barrel I completely forgot about the Wiser system. So I'm going to be pulling the trigger on one soon.

My go to hunting AR is my 7.62x39, with 123gr Barnes TAC-X bullets, it has done everything I've would ever want from the AR platform. It shoots all the bullets (3 different manufacturers) I use into the same group at 100 yards. I've pulled the can off it a dozen times without ever touching the scope.

I've never cleaned because it has never failed to fire a case nor fail to strip a round. It seemed to got dirty but never any worse. I'm tempted to clean it before my next hunt in a week but I'm a ain't broke dont fix it kind of guy.

Thanks for all the help guys! I will let you after tomorrow...plan to run some ammo through it to see how it runs with the gas block on it.

 

[md66948]

I was concerned about back pressure when I started looking into purchasing a Rifle Suppressor. I decided on a OSS HX-QD 762 Ti Suppressor because of their design. I am running it on several rifles in calibers 556, 6.5 CM, 7.62 x 39 and I will be setting up my Smith Ent. M21 today in 7.62 x 51. I am planning a bolt gun and AR15 Upper build in the new 6mm ACR. I will be running my OSS can on them and hoppefully reloading the 6mm ACR when reloading data is available.

My 6.5 CM is a bolt gun that I use for hunting white tails. All other rifles are semi-autos except for my Colt M16. I found that there is no back pressure issues with the OSS can. I have shot my Colt M16 with an AAC can and I got a lot of back pressure and dirt in my receiver from the back pressure.

I do reload for my bolt gun and my semi-autos. I only use factory LC ammunition in my M16.

The Military now issues the OSS HX-QD on their short range sniper rifles and the 6mm ACR Rifle.

Here 2 good videos on youtube of the OSS can:







I will post a Pic of my M21 with my OSS Suppressor Mounted on it. M14s don't handle Suppressors real well because of the back pressure and dirt flying directly into the shooters face.

Can is Mounted on my Smith M21.

 

[woodnut]

I'm a bit late, but I shoot cans on both my bolt rifles and ARs. I have a 6 Creedmoor AR10 that will not shoot factory Hornady ammo, but loves my handloads. I have an adjustable gas block, but even it didn't help the factory ammo. Two different people have told me, independent of each other, that it's the ammo, not the rifle. I can't help but believe Hornady used brass with "loose" primer pockets (and maybe real hot primers), as the primers would actually blow out. You may want to check your primers and pockets, just because....
A good can should not effect ES and SDs, but may be different from no can results. Cans do increase pressures, slow velocities a tad, like no more than about 25fps, but usually increase accuracy. Someone here pointed out the effects of shorter barrels on pressures and that's good to consider, too.
I had another AR 10 that double tapped. Found oil in the trigger group and when removed, it quit doing it.

 

[Privi457]

I have one can rated for everything up to 300 Win Mag. I use it on everything from 223 up to 300 Win Mag with no issues. In 223, 6.5 Grendel and 300 BO ARs I have changed nothing. Works fine w/no POI changes. Ditto in 20" heavy bbl Savage 308. In rifles with skinny bbls I do get a POI shift but no accuracy loss. Accuracy losses are usually due to bullet strikes in can..

 

[CaptnC]

Well...gas block did help pressure issues with load.

Tamed the recoil quite a bit. Which is why I bought an adjustable gas block in the first place.

Ammo that has worked fine in other guns (out to 24") had a lot of brass flow back into the bolt face. Same with the firing pin hole...primer is flowing back into firing pin hole in the bolt face.

But I had already backed off the powder charge on the bullet I want to use. It looks like I will go with it. 120gr Barnes TAC-X running at 2200fps should be ok out to 100 yards.

I also changed the settings in my Magnetospeed and it worked well enough to learn some things.

I think the shorter barrels dont like H335. My 18", 20" and 24" had no issues with that powder. My best velocities were with 8208...which is a huge surprise to me. None of my other Grendel's have done well with it.

Because I was thinking I might have to pull the hand guard I went dont to the long rang area of the range, so I did put up a target...just shot them into the berm.

When I was at 100 yards the latest load is hunting ready though.

 

[cohunt]

I got a 110 moving 2200 from my 8.5" b.o.

 

[Tulsa Reiner]

To be honest I have not done any load development for this rifle. I used loads that I had worked up for the 16" upper i had.

My thinking was the shorter barrel (10.5") would be less likely to be over pressure compared to a longer barrel.

I have an Aoudad hunt that feel in my lap coming up soon and was thinking about rushing the little 6.5 into service.

The property will not have any long range opportunities so I wanted my wife to use it. I like the ability to record the shots.



A little quick video through the lens of my ATN HD2 on my 7.62x39 AR. Pasted on a bigger hog looking for a pit pig.

I've got time to swap out the gas block and give it try before the hunt so there is still hope.

If she is only going to shoot to 100 yds, have you considered shooting subsonic ammo through a barrel with adjustable gas block? (It must have a 1:7.5 twist or faster for the bullets to be stable)
This was the solution I arrived at for my 5.56 AR. The upper I bought was by AAC (from MidwayUSA and I love the quietness of it, which might help her get more shots off at a sounder of hogs. You must shoot the heavier .223 bullets (73-75 grains) for stability also, available in subsonic loads by Atomic.

 

[Trnelson]

I have had a 20" Grendel AR for about six years. Mine is a carbine length gas system. I had similar trouble when i started working with a suppressor. You may try utilizing a heavier buffer as well as an adjustable gas block. It will help to keep the bolt locked up just little longer for allow the pressure to lower more before it starts to open. After installing a heavier buffer and a heavier buffer spring I actually ended up removing the adjustable gas block as I needed to set it to full gas to make it reliably function with factory ammo. Don't chase after upper end loads, you'll end up cracking bolt head lugs.