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Suppressors Looking for a 308 suppressor

MrOneEyedBoh

Sergeant
Full Member
Minuteman
Nov 23, 2011
546
7
37
Maryland, USA!
I'm currently on my cell and won't have any time soon to get on a desktop. What I was wondering is, is there any good stickies in choosing the right suppressor? I want one so I can shoot on my property, but I dont know if a suppressor will actually work that well on non-subsonic rounds. Thanks fellas.

I do know I'll have to re-zero again.

This is going to be on a precision bolt gun so the POI is a big deal... So fat I found the TBAC 30ba seems nice.
 
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Well is a relative term. A decent can will make a 308 sound like a regular 22. Should you decide to load subs itll sound like a loud air rifle but you'll need a fast twist 308 to accomodate the heavy sub loads.
 
Thanks. Its on a precision bolt gun. So POI is going to be a big deal... Looks like a TBAC 30ba is recommended a lot...
 
If your going to shoot suppressed all the time POI is not a big deal to me. Re-zero to the shift and your gtg. Now, POI shift shot to shot is another story. If cost was not a factor my choices would be as follows:

-Surefire
-TBAC
-TTF
-Shark
-Liberty
-AAC (Direct Thread models)
 
The supersonic crack of the bullet breaking the sound barrier on full power 308 rounds will sound like a 22LR with no suppressor or maybe just a tad louder. THE BULLET makes this sound and no suppressor will stop it.
Loading your ammo to below about 1050fps will prevent this crack and your gun will then be "hollywood quiet". The loudest noise with mine is the bullet hitting cardboard downrange.
The subsonic ammo has a lot of limitations due to the low velocity. I pretty much just use subs for suppressor demonstrations and maybe shits and grins. I don't hunt with it, but as long as you limit your range and use precise bullet placement it should work for you.
The crack from supersonic rounds follows the bullet downrange, making locating the source of a shot hard to determine. I stood behind a big oak tree near the hundred yard mark on my range while a buddy shot my 308 AR from the bench. I never heard a sound from the direction of the bench. The only sound I heard came from the point where the bullets path was closest to my position, about 30 ft to one side of the range. It sounded just like someone standing at the 100-yd mark shot a 22LR.
 
Thanks. So basically a suppressor will sound like a 22 to the neighbors... Right? Or should I just say the hell with a suppressor and deal with them later? I dont want enemies ya know? At least they may not be able to pin point who is shooting right? Less likely they would here its me?

Should I go QD or threaded... Does the suppressor hinder the fact that I shoot long range in terms of performance? I think I'd like QD just so I CAN take it off, but I've read here and there that the threaded makes or more accurate/quiet
 
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I dont notice much if any poi shift with my yhm titanium 7.62 qd but I've only used it on my 300blk ar. My 5r 308 is heavy enough without a can hanging off the end. Im going to go with the tbac 338ba eventually since I plan on a 338lm latrr on. The ba series are very nice for what you're talking about doing.

308 through a can will sound like 22lr unsuppressed or 17hmr depending on the load in the 308.
 
I only own 1 suppressor and it is QD. I went QD because I have several AR types in both 308 and 556. I can use the same high-dollar suppressor on several different guns. I only have to buy adapters which I can find on the net for roughly 70 bucks for the YHM. Far as I can tell, you'd have to be a helluva lot better shot than I am to tell any accuracy difference between QD and direct thread. Even if you could it would be hard to make me a beleiver. And with supersonic ammo the crack of the bullet will drown out any sound difference. I'm sure there are plenty of studies done by smart people with sensitive equipment, but I only have my ears to rely on and that's good enough for me.

POI shift with mine is anywhere from non-existant to about 1.5MOA on my guns, and most important it's repeatable. If it wasn't titanium it would be much heavier and this would make POI shift much worse. If you buy one, I suggest you get the titanium option. Somebody will jump up and holler about titanium and heat failure, but if you don't go full auto or do 10 mag dumps back to back you got nothing to worry about IMO.

I was somewhat disappointed in mine when I first fired it on my AR. It was the first time I'd ever fired a suppressed weapon bigger than a 22. The bullet noise is much louder than you'd think and makes up a good portion of the noise you hear when you fire a weapon. After a lot of experimentation I have come to realize it actually does an excellent job of mitigating muzzle blast, which is all any suppressor is capable of.

All this said, I must remind you I have never owned/shot a direct thread suppressor so I can only speak from my experience with QD. But IMO the good points of QD are:
Ease of use on several different weapons regardless of different thread patterns.
The adapters stay on the barrel and saves wear and tear on your barrel threads which are very fine pitch and could easily be cross-threaded.
The adapters whether flash suppressor or brake will serve as a sacrificial blast baffle and will help protect your expensive suppressor internals from erosion.

I've heard of some brands of suppressors having trouble with QD mounts, but the YHM mount is so simple and robust I don't see much potential for trouble. The ratcheting lock plate keeps mine from backing off quite well.
I wish I'd had one 30 yrs ago now that I bought one, and my neighbors probably do too.
 
Thanks bro. Im kinda thinking about getting the QD so I can use it on other platforms. Im just hoping that with me using a suppressor the neighbors dont know its "me" and all they hear is a shot in the woods... I dont mind, but I dont know what they would do. I will be in full compliance of the law, so nothing there but I dont want enemies like I said before.
 
How far away are your neighbors?

My OCD tells me thread ons will come loose so I'm constantly checking it. I like the QD version suppressors because it is a positive lock in my book.

Have not noticed much difference in accuracy b/t thread on vs. QD in my rifles.

All POI shifts are repeatable.
 
Its hard for me to get used to a thread on as they do back off and Id constantly be grabbing the can to make sure its still tight. With my can Ive put 300 rounds through it in a range session with no problem at all. Its worth it to me for the added safety. Maybe on a super precision gun a direct thread would make a difference enough to warrant the hassle of checking its tight but my ARs shoot just fine with my can. Sub moa with PMC bronze at 100yds and 4x scope is plenty good enough for me. My 300blk isn't quite as accurate but its got a terrible trigger too and the chamber inherently keeps the bullet way off the lands so its got a bit working against it from the beginning.

Your neighbors will know youre shooting, the only thing the can is going to do is keep them from hearing really loud gun shots vs 22 loudness shots. Only way you can shoot and them not know it is to shoot subs.
 
IMHO, if I had to do it all over again I would have just bought my aac titan qd for all my bolt guns. Expensive, but was worth it. Best can I own for a bolt gun hands down. Surefire, aac, and YHM are all great cans. TBA as well. research silencer tests online and talk to people as you are doing here, there is no one best can, only better manufacturers. Don't rule out thread on cans, saves cash and takes away some db. Either way make sure that who ever threads your barrel knows what they are doing. As far as the neighbors go, the key is to not to release the fact that you are using A can in the first place. Most people have no idea that your even shooting a rifle when they hear the sonic crack of the projectile. People tend to worry more about the muzzle blast then anything else. Only time I ever have had issues with can noise is when I'm playing with full auto stuff, but even that is very rare.
Good luck in your decision,
Jesse James
 
Thanks man. The BBL I have is already threaded. I bought it from someone a while back. I guess I would have to get the threads checked?
 
Surefire rules the roost as far as Cans go. Unless you plan to buy a bunch... Buy a mid sized .308 can so u can shoot lesser cals on it. What really sets them apart is the mounts.

THE AAC SDN6 is a good can, but the mount is kinda crappy. For that reason I would stay away from AAC.

Surefire
Ops Inc - Bit dated but very good cans, used by military and good mounts
Griffin Armarent - Has some really nice designs, very good mounts and price is on the lower end. That would be my reccomendation if you don't want to drop surefure coin or recontor your barrel fro OPS. They are sorta reflex cans so if they add less legnth than many other designs.
New KAC cans are supposed to be the shit, but I cant get over their mounts and no way in hell im paying $300-400 for a fucking mount.
 
Thanks man. The BBL I have is already threaded. I bought it from someone a while back. I guess I would have to get the threads checked?

Yep. Many times they will thread it off the OD of the barrel and not the bore center. This can cause baffle strikes. It could also have been threaded by a tard so have it checked out before you put a $1000 can on there.
 
Yeah.. I posted a thread on recommendations on where to send it.. Im in MD, so not far from you... You know anyone local or in NOVA that does it?
 
I own a surefire 762SS and I love it. One of my rifles displays a POI shift and the other does not, I think it is rifle/barrel dependent. The shift I do get on the one is extremely repeatable. On the bolt gun I regularly shoot subsonic and the ones I load are repeatable and consistent out to 300YD (although it isnt hitting very fast at 300). As far as supersonic it does sound like a 22, maybe a bit louder, but definitely has a different report. If you shoot consistently your neighbors will eventually know its you, or your direction.

If you want to shoot a supersonic round it is going to be limited by the velocity. As someone said above the breaking of the sound barrier is what is making the noise. Good luck.
 
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Surefire rules the roost as far as Cans go. Unless you plan to buy a bunch... Buy a mid sized .308 can so u can shoot lesser cals on it. What really sets them apart is the mounts.

THE AAC SDN6 is a good can, but the mount is kinda crappy. For that reason I would stay away from AAC.

Surefire
Ops Inc - Bit dated but very good cans, used by military and good mounts
Griffin Armarent - Has some really nice designs, very good mounts and price is on the lower end. That would be my reccomendation if you don't want to drop surefure coin or recontor your barrel fro OPS. They are sorta reflex cans so if they add less legnth than many other designs.
New KAC cans are supposed to be the shit, but I cant get over their mounts and no way in hell im paying $300-400 for a fucking mount.

Except for sure fires are louder and more expensive than a lot of other cans of the same quality in my experience. I like the SAS Arbiter for .308. Innovative arms has the best value centerfire cans in my opinion, and Phil is a great guy to boot. Ive shot ALL of his cans side by side with all the big name cans and was really impressed, then I learned the price and was more impressed.
OP, it's a lifetime purchase, and will be your first of many. Find someone local and shoot several.
 
The KACs are loud and heavy compared to the competition too, though they are stout. We did manage to wreck one on an M249 though.
 
Surefire rules the roost as far as Cans go. Unless you plan to buy a bunch... Buy a mid sized .308 can so u can shoot lesser cals on it. What really sets them apart is the mounts.

THE AAC SDN6 is a good can, but the mount is kinda crappy. For that reason I would stay away from AAC.

Surefire
Ops Inc - Bit dated but very good cans, used by military and good mounts
Griffin Armarent - Has some really nice designs, very good mounts and price is on the lower end. That would be my reccomendation if you don't want to drop surefure coin or recontor your barrel fro OPS. They are sorta reflex cans so if they add less legnth than many other designs.
New KAC cans are supposed to be the shit, but I cant get over their mounts and no way in hell im paying $300-400 for a fucking mount.

Surefire doesn't rule anything these days. They are being caught up to and passed in the suppressor world. They are loud and over priced. Their mounting system is great and the POI is repeatable but it is not a 0 shift like they claimed at one point.
AAC 762SD-N6, here we go again..... the can was never intended as a precision rifle can. Although, its predecessor was. On a 300 blackout they perform great. The mounts are junk but they can be adjusted by the end user and still be a great can.
KAC takes a huge backseat on suppressor technology. Their stuff is old tech, heavy, and they mounts are atrocious by comparison.

The best 30 cal cans on the market are going to be a toss up between Thunder Beast Arms, Mack Bros, and AWC THOR Ti. If you want QD just make sure and ask for that option when ordering.
The YHM Ti Phantom is pretty good as well, its more of an entry level Ti suppressor. Also look at Templar Tactical, I am impressed with their Archangel can.
 
Surefire doesn't rule anything these days. They are being caught up to and passed in the suppressor world. They are loud and over priced. Their mounting system is great and the POI is repeatable but it is not a 0 shift like they claimed at one point.
AAC 762SD-N6, here we go again..... the can was never intended as a precision rifle can. Although, its predecessor was. On a 300 blackout they perform great. The mounts are junk but they can be adjusted by the end user and still be a great can.
KAC takes a huge backseat on suppressor technology. Their stuff is old tech, heavy, and they mounts are atrocious by comparison.

The best 30 cal cans on the market are going to be a toss up between Thunder Beast Arms, Mack Bros, and AWC THOR Ti. If you want QD just make sure and ask for that option when ordering.
The YHM Ti Phantom is pretty good as well, its more of an entry level Ti suppressor. Also look at Templar Tactical, I am impressed with their Archangel can.

But but but, they've got to be good, I was issued one when I was in CAG, right after BUD/S, but before ranger school, while I was dual enrolled in SOTIC and RSLC, while finishing up the Q!

I like all the above, but would put the AWC a little below some of the others you mentioned. The downside to the SAS is getting one. I have found the only way to get a can that has all the features I want is to Form 1 it, and blatantly copy some features. It seems you may have actually used some of the silencers you mentioned....
 
But but but, they've got to be good, I was issued one when I was in CAG, right after BUD/S, but before ranger school, while I was dual enrolled in SOTIC and RSLC, while finishing up the Q!

I like all the above, but would put the AWC a little below some of the others you mentioned. The downside to the SAS is getting one. I have found the only way to get a can that has all the features I want is to Form 1 it, and blatantly copy some features. It seems you may have actually used some of the silencers you mentioned....

I would disagree with you. The AWC is quite impressive. The accuracy and minimal shift in POI from can on or off is what impresses me each time I use them. For a thread on can, they are some really high tech pieces.
I dont really get hyped up about SAS. I have one, they are nothing to jump up and down over.

All of the cans I mentioned in the post I do have time with, I own them and use them everyday. How much time on a AWC Thor Ti do you have?

The three I listed are a dead tie for me. They all perform but have their minor differences from one another.
 
Honestly, not much time on it. The only one I played with had waaay loose threads. However, it was still in the dealers possession, so they may have had awesome customer service and fixed it. Not really a good basis to judge a model over all. My liking for the arbiter is that it always gets shot next to a cyclone, so it kind of makes it shine. ( I really like the cyclone, I'm not trying to knock it) almost no POI shift, to my uncalibrated ears they have the same sound reduction, less weight, and paid the same for them. For a tank of a thread on for the win. Mag, I still like the innovative arms. I've got a yhm ti qd as well, and since the trade I made for it came out to where I paid about $375 for it, I'd say it's a good can for the money too. I'm building a form 1 Ti can now that is kind of a culmination of several top cans. Bottom line, I'd take any one of the ones you or I mentioned, but wouldn't take the surefire or KAC even at half the price.
 
The loose threads may have nothing to do with the can and everything to do with the barrel threads. I've had some cans that would not thread on at all, some would wobble, and some were so tight you could have put the can halfway on and shot with it.
It's all in your barrel work.

I've had time behind or own a lot of different suppressors. I love them, can't help it or explain why. I just am a suppressor addict. Surefire is OK but they really need to come off their pricing, for what you are getting they are high dollar.
Generally all the KAC are over welded tubes of steel. They went way to industrial with them, making them very heavy and cumbersome. The only can they have that is remotely worth a shit is the NT4, and that is not saying much.
The only reason I bought said NT4 was because a stocking dealer offered it to me at a 50% discount and was ready to go ASAP. He said he ordered 3 and it took him 2 years to sell the first two. They just don't have a good rep in the private sector.
 
I can't speak for other models but I am completely impressed with my 30P-1. Shift is minimal and thus unimportant to me. What is important is shot to shot repeatability first to last. I shoot it on my 308 and my AR in 223 and it is repeatable first shot to last on both. The 308 shifts down .5 and right one inch. The AR shifts left .5 and down .5 at 100 yds which is no problem to adjust for. The rifles are just as accurate with the can on as without. I have shot the 308 out to 500 with the supressor and it is just as impressive at 500 as up close at 100 accuracy wise. Thunderbeast has a good rep on the Hide for good reason and I appreciate they guys for turning me on to it. The guys at Thunderbeast got them to my dealer without a bit of dicking around and he had never ordered from them until I told him about TBAC.
 
I've had time behind or own a lot of different suppressors. I love them, can't help it or explain why. I just am a suppressor addict.

that's weird, maybe we are twins, separated at birth? Are you crippled and REALLY ugly too?
 
that's weird, maybe we are twins, separated at birth? Are you crippled and REALLY ugly too?

Crippled, no.... just had surgery on my guts if that counts?

Ugly... I sure as hell hope not! :D My wife seems to still like me, so I will stick to that.



You make yourself sound like the troll off Ernest Scared Stupid. :(
 
Lol, if the VA did it you'll be crippled before long. I'm still laying here 3weeks after a surgery with a two day recovery time.
 
For the OP: I have no opinion, since I have no knowledge here.
However, I support your idea of dropping the sound down to 22 vs 308 - psychologically, the sound of the 308 is inherently striking and alarming from a distance, while the 22 sound just does not draw the fearful, wary attention the same way.

for the money, I think the good relations might be worth it, plus you will feel more relaxed vs wondering if you bother the neighbors.
 
Just keep in mind, once you buy one good can, you will never actually be able to save money again.
 
Delta4-3, PM me if you get time, I would like to discuss the Cyclone with you. You and KYS are the only people I've really seen that have a substantial amount of time on one. KYS had nothing but good to say about it except it was heavy, comparatively speaking.

To OP, if weights not a huge issue BookHound has a brand new AAC Cyclone in the F/S section for $585.
 
Surefire doesn't rule anything these days. They are being caught up to and passed in the suppressor world. They are loud and over priced. Their mounting system is great and the POI is repeatable but it is not a 0 shift like they claimed at one point.

My Surefire FA556AR has absolutely no point of impact shift. Also, it is very quiet. I only hear the crack of the bullet. They are not overpriced.

It is important to realize that the more robust construction of the suppressor, the better it will hold up. Meanwhile, the military decided to go with the Surefire:

Defense Review - SureFire Suppressors Wins USSOCOM Family of Muzzle Brake Suppressors (FMBS) Contract for Rifle Suppressors (Silencers/Sound Suppressors) and Flash Hider/Adaptors

It was only after shooting with a suppressor that I realize how important all of things Surefire brings to the table actually are.

Just my two cents.
 
My Surefire FA556AR has absolutely no point of impact shift. Also, it is very quiet. I only hear the crack of the bullet. They are not overpriced.

It is important to realize that the more robust construction of the suppressor, the better it will hold up. Meanwhile, the military decided to go with the Surefire:

Defense Review - SureFire Suppressors Wins USSOCOM Family of Muzzle Brake Suppressors (FMBS) Contract for Rifle Suppressors (Silencers/Sound Suppressors) and Flash Hider/Adaptors

It was only after shooting with a suppressor that I realize how important all of things Surefire brings to the table actually are.

Just my two cents.

Well, let's get right down to the nuts and bolts of it. I never said Surefire suppressors were not a good product. I said they are

A) Overpriced for where they stand in the technological aspect of suppressors in todays market.
B) Compared to the latest technology in suppressors (Ti tubes) they are still overpriced.
C) You claim no impact shift..... which is funny because I have that same exact can on a 14.5" AR15 and it shifts about 2" low at 100 yards. It's repeatable but still there is a shift from zero without the suppressor.
D) The military goes with about 5 or 6 different suppressor manufacturers so lets not hype that up to much. Every branch can solicit different requirements and contracts. AAC won a military contract for their 300SD as well as the Titan.

Let's Compare pricing:

Surefire FA762SS - I have found them anywhere from $1750-$1900.00 on various websites and one local store. (with no muzzle device)
Thunder Beast 30BA - $1100-$1200.00 with one muzzle device.
AAC 300SD - the latest in Ti mag rated technology. 13oz can @ $1700-$1800 with no brake.

I own a few Surefire suppressors. They are more of a harsh environment, hard use, anything goes type suppressor. They are not the most quiet can on the market by a long shot.
When bringing things to the table, make sure you have more to go off of then just an internet report. Usually first hand experience is more valuable then something you read on the net.
I am not bashing Surefire, just giving my honest evaluation compared to the other suppressors I use. I still use and support their products but for a guy on a budget wanting a do all, best bang for your buck suppressor.... I just can't say that it's Surefire.
 
Surefire seems to be a jack of all trades IMHO.

They aren't the heaviest, yet not the lightest.
They work WELL, but aren't the most quiet.
A lot of them have little to no POI shift, but not all of them.
They aren't the shortest suppressors but they aren't the longest either.

Surefire is however the most expensive on the market and considering the current market they do need to get their prices in check. From a business stand point though, why reduce your prices when people are still paying them.
 
Surefire seems to be a jack of all trades IMHO.

They aren't the heaviest, yet not the lightest.
They work WELL, but aren't the most quiet.
A lot of them have little to no POI shift, but not all of them.
They aren't the shortest suppressors but they aren't the longest either.

Surefire is however the most expensive on the market and considering the current market they do need to get their prices in check. From a business stand point though, why reduce your prices when people are still paying them.

I agree to an extent, but they are not worried much about the civilian market. Much like KAC and AAC they are banking on military contracts. Who cares if the civilians are buying one can at a time for 1900.00 dollars? You have them being sent to military units by the 100's.
I like their gear but at some point you have to really sit down and be like is this economical or could I have went with a TBAC 30BA + my tax stamp and still come in $400.00 less then a SF without your tax stamp. People always forget to factor in that tax stamp cost and it can really be the things that drives you over the budget.
 
I have 5 and I like my Dakota and AWC's steel and Ti as well as any I have seen or heard My SWR and my YHM are not far behind either.
So many swear about TBA I would think that is a very good choice also but one I have not used or seen used. GL PG
 
I'll double what some people are saying here. I shoot on my property and neighbors are 200-300 yards away (it is legal, I do have a berm). I shoot my 308 bolt and 223 AR and people think it is a 22. In fact, they cannot hear it if they are inside their homes, just outside. And people shoot plenty of 22 around here, so no big deal. Not so if it was unsuppressed. Then they would hear "HIGH POWER RIFLE!!!!" and be alarmed, which some of my neighbors are ninnies.

Now more fun, I shoot 22 bolt gun standard velocity with a Silencerco Sparrow, NOBODY knows it inside, outside, including my family even though I shoot from the back garage door. I took out a squirrel recently while the family was getting ready to go out front, they had no idea.
 
Do the buy once cry once route. I went with the old Thundertrap and SAS Arbiter. Super happy and both are thread on cans. No complaints.

They both are not cutting edge quiet right now but they work fine and I took mines out to 1400 yards or so with some issues with my .308 but I made it.

Surefire is nice on the .223 cans, but the .308, it's just made very durable and not so quiet.

These are my own experiences.
 
AWC Thundertrap is a nice suppressor! I own a 338 Thundertrap, it lives on a 6.5 SAUM and performs great.
 
So much talk of the biggies out there. I have mostly steered away from them for no particular reason other than I like supporting homegrown innovation. I have experienced a few SRT cans (Cheyenne XXL .22, Hurricane XL 5.56, Shadow XL Ti .30), a couple Sharks (Thresher 5.56, Shark .30), and some Fishers (.30 and .22lr) with great results. What experience do ya'll have with some of the small manufacturers?

To get back to the OP, I like the thread-on SRT Shadow XL Ti for minimum POI shift, light-weight and quietness. For a .30 can, it seems just as quiet on my 5.56 bolt gun as any dedicated 5.56 can every did.

Good luck going quiet! And have you thought about telling the neighbors what you are up to? Invite them over for a deer BBQ and a quiet-gun shoot. They might like it! And its always better in the long run to have them on board. You want to enjoy pulling the trigger! You don't want to be wooried about who is after you all the time... in my opinion.
 
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Yeah.. I posted a thread on recommendations on where to send it.. Im in MD, so not far from you... You know anyone local or in NOVA that does it?

You don't need to pay to have it checked, there are multiple ways to do it yourself for free.
 
I shoot an AAC SDN6 in front of a Rem700 5r, POI change is ~2" (moa) at 100 yds and relatively the same as far 600 yds. Shooting a 175BTHP at ~2600fps. Does sound about like a 22 with supers. When the can is on my 300 blackout with subs it sounds like a paintball gun. During xmas i went to visit the parents, they are on the edge of city limits and there is nothing behind there house. This crow was messing with my dads purple martins, pulled out the 300 blk. My mom was about to shit a brick, dad thought it was cool. After I shot, my mom had this smile on her face; wow that thing is really quite.

Felt like rambling, hope the story gives a little perspective.
 
I shoot a Jet titanium can. Lightweight at about 17 ounces for a .300WM rated can.
POI shift is so minor, it isn't worth correcting for on my new barrel (Schneider SR60 contour)
My original factory 5R barrel , on the other hand, had significant POI shift. The barrel shot very well, with or without the can but shoft was about .8 mil up and .2 right (this was after testing multiple cans on the same rifle AND another, control rifle), which is why I changed the barrel out.

I only bring up the original barrel as something to consider.
 
I would guess that the factory barrel threads were not concentric to the bore and thus caused the shift.

My original factory 5R barrel , on the other hand, had significant POI shift. The barrel shot very well, with or without the can but shoft was about .8 mil up and .2 right (this was after testing multiple cans on the same rifle AND another, control rifle), which is why I changed the barrel out.

I only bring up the original barrel as something to consider.
 
I would guess that the factory barrel threads were not concentric to the bore and thus caused the shift.
Barrel was originally 24", we cut the barrel back to 20", the shift was the same. The barrel was funky for sure, but it shot VERY well.