silencer causing massive spread?

MarcinG

i wrote long thing but here is short version:
brno 2-e (not cz 452 as i thought) with SAK silencer. worked ok and out of sudden started to shoot all over (out of 4 shots to A4 piece of paper from 25m 1 missed target completely and other 4 were spread from 10cm left of POA to 10cm right.
after removing silencer (figuring out that it was silencer costed me about 300 rounds and lot of bad language + 3 mornings not to mention walking up and down and changing target boards) i'm easily down to 1.5x1.5 inch at 50m with subsonics (i know i'm not elite sniper but i does me ok for start). silencer looks hard to mess with (SAK- solid aluminum + 2 caps + can ) and it look like it is straight. (i cleaned it some time ago in hoppers9 and it shoot ok at least one day out afterwards if my memory serves me). picture attached shows said silencer (way cleaner than few weeks ago when it shot just fine).
question 1 is this normal as silencer just malfunctioned?
question 2 will buying new one solve it?

PS i used it with at least 4 types of ammo it looks same every time.

skipking

take it apart and clean it out

Flynn89

The 1/2 inch thread may be damaged and need a re-tap

MarcinG

The 1/2 inch thread may be damaged and need a re-tap

looks fine and fits tight.

take it apart and clean it out

it actually happened after cleaning but i will have look at it again. (it is not clean by any means but it is way less dirty than it was - it was almost stuffed with lead).

thanks.

Cass

Give me a picture of the muzzle off the mod. Both inside and outside of the end cap (muzzle end)

One reasons a rife fires worse with mod on than off. Improper alignment.

This can be caused by a poor threading job of the rifle, a poor threading job on the suppressor, both, or an imperfection in the suppressor that causes it to sit well on the rifle but actually be misaligned with the bore.

The picture of the muzzle of the suppressor will tell you. If the rounds are clipping the the muzzle of the suppressor this will give the poor grouping/lack of grouping and also make is completely inconsistent. IOW if it were a scope, rifle issue you'll find the error is consistently doing such a thing. With such complete randomness it has to be the suppressor.

If there is no visible marking on the outside of the end of the suppressor, then take it apart and check the inside of the end/muzzle cap of the suppressor. It may be very subtle. It will not be a big chunk out of it. It'll look like a wear mark or brush mark. You'll see bare metal instead of a painted surface.

Grizzly 45

If you can check your scope on a different rifle too. I thought I had silencer or barrel problems on mine too until I changed the scope and found that a POS scope was the problem,and make sure you have the can on tight as well to the same" tension"if that makes sense?IOW if you tighten hand tight,make sure it stays hand tight after a few shots.as any loosening can affect the barrel harmonics too and cause group wandering not to mind damaging your can.

MarcinG

Cass wrote: »

Give me a picture of the muzzle off the mod. Both inside and outside of the end cap (muzzle end)

it is single chunk of metal would need boroscope to take picture of inside end. outside attached. I tried to run cotton bud to see if it catches anything but not. it looks like aluminum is covered in grey dust (lead deposite?) and has few streaks showing actual black painted aluminum. there may be a few places where bare metal is visible but they all looks like scratched by needle.

One reasons a rife fires worse with mod on than off. Improper alignment.

yes can imagine. what i can't is how come single piece of metal (caps nor tube are even remotely close to get in contact with bullet) can screw on wrong way without crossing thread.

This can be caused by a poor threading job of the rifle

they are looking fine (attached if works finding it bit frustrating to work with pictures)

i think i will take it apart and see maybe it is clipping inside. but then i would imagine rounds will keep on getting stuck inside/create great feedback of something going wrong.

MarcinG

Grizzly 45 wrote: »

If you can check your scope on a different rifle too. I thought I had silencer or barrel problems on mine too until I changed the scope and found that a POS scope was the problem,and make sure you have the can on tight as well to the same" tension"if that makes sense?IOW if you tighten hand tight,make sure it stays hand tight after a few shots.as any loosening can affect the barrel harmonics too and cause group wandering not to mind damaging your can.

I changed scope recently but it started to happen before i did. as i said i will get onto vice and pop it open after work.

very moment i took silencer off the gun i got from 20cm random spread on 25m to 3cm spread on 50m (and i blame myself for spread +- inch at 50 meters as i m not experienced at all).

fabwing

I am having the same problem with the sak mod on my .22 it seems there is a mesh towards the front of the sak mod, it looks damaged and out of shape,this can be caused due to cleaning the mod with a pull through etc ,its only six months old and not used very much maybe 300 rounds.

MarcinG wrote: »

I changed scope recently but it started to happen before i did. as i said i will get onto vice and pop it open after work.

very moment i took silencer off the gun i got from 20cm random spread on 25m to 3cm spread on 50m (and i blame myself for spread +- inch at 50 meters as i m not experienced at all).

clivej

Can you remember if the mod got a a bang?? Could have knocked it off center a bit, enough to deflect a round.

Strip it, Clean it. I found soaking in neat washing up liquid to soften the crud up and then use a toothbrush to scrub it with did the job for me.
Some say to soak in coke or diesel over night to soften the crud up as well.

The least little deflection at the muzzle will knock the round off a lot at he target

MarcinG

So how about putting it into a vice and drilling out all but threaded part to 6mm ? After work i will try to take it apart and see if any signs inside.

Cass

MarcinG wrote: »

it is single chunk of metal would need boroscope to take picture of inside end. outside attached. I tried to run cotton bud to see if it catches anything but not. it looks like aluminum is covered in grey dust (lead deposite?) and has few streaks showing actual black painted aluminum. there may be a few places where bare metal is visible but they all looks like scratched by needle.

As i said above and as Clivej said too:

Cass wrote:

It may be very subtle. It will not be a big chunk out of it. It'll look like a wear mark or brush mark. You'll see bare metal instead of a painted surface.

clivej wrote: »

The least little deflection at the muzzle will knock the round off a lot at he target

If there is an issue with alignment it does not necessarily have to be big. The most gentle of touches will knock the bullet of trajectory and give you this random pattern you're experiencing. I had it before, but with a 30-06. Trust me if the bullet got caught with that it would destroy the suppressor and possibly the end of my rifle.

The holes in the suppressor are bigger than the bullet. In some cases cases quite a bit more. This allows a certain amount of improper alignment to be present without affecting the performance. On my 30-06 i seen nothing on the end of the muzzle of the suppressor. However when i took it off (it did not screw apart, one solid piece) i noticed the most subtle of scratch marks on the inside lip of the muzzle of the suppressor. I measured the diameter of the muzzle of the suppressor and then increased it by 2 mm using a drill press. Put it back onto the rifle and problem solved.

This may not work for you unless it's the muzzle end of the suppressor causing the problem hence the need to identify what is causing it before doing any work.

yes can imagine. what i can't is how come single piece of metal (caps nor tube are even remotely close to get in contact with bullet) can screw on wrong way without crossing thread.

It doesn't have to be on the wrong way. The threads, if its an old rifle, can be worn down over time and usage. The suppressor itself may be imperfect. There are a number of reasons alignment may not be 100%. When talking about imperfections and most measurements with firearm you're looking at thousandths of an inch upward. So small you cannot see it with the naked eye.

So it's possible to miss something just by looking at it and possible to disregard a possible cause because it just doesn't make sense that it would be that part causing the problem.

they are looking fine (attached if works finding it bit frustrating to work with pictures)

From looking at them you seem to have an issue with the top (as i look at it) of the suppressor. I've marked it in the picture. It looks marked and not just from the gases, but from actual contact.

i think i will take it apart and see maybe it is clipping inside. but then i would imagine rounds will keep on getting stuck inside/create great feedback of something going wrong.

As said above not necessarily. If it is the bullet clipping the suppressor then it takes only the most minimal amount of contact to knock it off trajectory. The .22lr does not carry a great deal of power or pressure so any feedback may be so subtle you're not noticing it.

I assume you have tried the rifle with the Mod off? I also assume it's working fine without it? Just making sure because if everything works fine with the suppressor off then it's definitely it. If it doesn't then the suppressor may not be the issue.


Last thing. Do you know anyone else with a suppressor. Same one if possible but if not not a major ordeal. If you do get their one and try it. If it works then it's your suppressor. If it doesn't work then its the rifle threading.

clivej

WITH THE RIFLE UNLOADED

Look at the end of the muzzle, not cleaned, you should be able to see a 'Star' shape of the powder on the end. The 'legs of the Star' should be even to show that the muzzle crown is good. Same with the end of the mod you should be able to see the 'Star' markings to show an even discharge of the bullet when leaving the mod or muzzle.

That star marking is just burnt powder residue, soot for a better word, .

Cass

I seen that too, but the one bit i highlighted is not like the rest. If you look at the left picture you can see the "star" shaping form the discharge. If you look at the right picture you'll notice this marking is larger and goes from the inside to outside of the muzzle of the mod. Also right o the edge (crown if you will) at that point there seems to be damage or wear which should not be a factor if it was merely the pattern of the discharge.

Not saying it is the problem but it's where i'd start.

MarcinG

Just looked into my silencer. Is this silver ring around holes normal or is it indicating that whole aligment is gone? Ps all holes are more or less scratched but i need to clean it before i can see properly.

MarcinG

hi forum went down very moment i was uploading pictures (no it wasnt me ;P so:
i took it apart and found that there is like silver ring around every hole in silencer a bulet travels through (still can't add pictures). It looks like there is something going on around edges so i took a drill and drilled out holes from 6.5-7mm originally to 8.5mm and thn cleaned whole thing to bare aluminum with brass brush on dremel. it looks like it solved the problem. thank you very much. Ps when i think about it i think that 1st time i ever noticed this randomness in shooting i also noticed that my silencer was loose so maybe this caused whole thing (as i said it took me a while to discover that it was silencer - if one will look to my thread about ejecting etc i'm complaining about zeroing scope on windy day. it wasn't wind it was my silencer acting up.