Thread: Suppressors - POI Change and Sound Reduction.

The suppressor on my Anschutz .22 rimfire does not seem to change the point of impact much at all.

By fitting the suppressor on my .223, the point of impact changes about two inches at 25 yards.... mostly in elevation, but maybe half an inch in windage. I can't recall whether the point of impact is lower or higher with the suppressor now, but I have sighted the rifle with the suppressor on and I regard it as the most accurate centrefire rifle I've owned.

I have a well-made, compact Waitaki Engineering suppressor I use on my Bergara BA13 .357 magnum. These rifles have sturdy little barrels and I was surprised to find that the small suppressor changes the point of impact so much. I handload all my ammo for this rifle. When I shoot 200 grain projectiles going 960fps, I find that these hit about three inches lower (at 25 yards) with the suppressor fitted. Oddly, when I shoot 158 grain bullets at 1520fps, the point of impact at 25 yards can be 1.5 inches higher compared to when I shoot with no suppressor.

Although I've been using rifles for years, I have only just started to contemplate things like barrel harmonics since I've recently started experimenting with the .357. I realise how much I don't know.

I now have two Bergara .357 magnum rifles. I want to dedicate one to shooting with open sights, and the muzzle-forward Waitaki suppressor allows me to do this. The other one is intended to be a 'quiet' rifle shooting subsonics and I want to eventually get a large, effective suppressor for it. Because subsonic cast bullets generally don't expand much, accuracy is of prime importance so I have fitted a scope to this rifle.

I'd really appreciate hearing recommendations as to what brand or type of suppressor is likely to to be the quietest for this new rifle. I'd also be interested in any comments about point of impact shift due to a suppressor being fitted. Thanks in advance.

It is common to have POI shift with suppressor, just sight in your rifle with the suppressor on and shoot with it.

Normally the bigger the longer suppressors have better sound reduction, but considering the weight and the length of the whole setup, you make your only decision.

Aim sport 50 suppressor, dpt (need to add more baffles to get best sound reduction), gunworks 50mm maxius suppressor, hardy are all very good.

Before fitting supressor to our 357 found 38 subs would shoot lower , which I expected obviously , but also around an inch off to the left over 25 meters , compared to 357 , which I wasn't expecting.
After fitting supressor they now both shoot straight (but obviously 38 still lower) which I found a bit strange. Funny how that works. Harmonics must have quite an effect.

Thanks for the comments and ideas.

Ftx325... What is the model of .357 rifle?

Although I need to do some more experimenting to test my ideas, it seems that when I was resting my rifle directly on the benchrest 'sandbag" I had accuracy problems when shooting my faster .357 loads.

My 158 grain bullets travelling at 1520 fps create a relatively savage recoil compared to my slower loads. I went to the range for my latest session and there is a bench with a scissors-jack sitting on it. On the jack platform there is a small, stiff bag filled with gravel. I used it like I've seen others using it (I didn't grow up with bench rests) and my grouping was poor with the faster loads. I feel, quite strongly, that it is better to hold the fore-end firmly... just as I would try to do when shooting in the scrub.

So next time I go out for a shooting session, I'm wondering how different my point of impact might be (suppressor or no suppressor) if I stop using the hard front support and instead hold the front of the rifle while resting against something softer. Sometimes when I have tested a rifle on private land, I have simply sat down and used either my knees or a set of two kanuka shooting sticks for support and the results have been more than adequate. I prefer to lie down and rest on a pack or something, but the steep land... and the requirement to shoot in a safe direction... makes it more convenient to use the sticks.

Fortunately I love going to the range. And it is good to have a challenge. I am likely to learn something from all this.

Originally Posted by Coote

Thanks for the comments and ideas.

Ftx325... What is the model of .357 rifle?

it's a Marlin 1894 SBL lever action ... Looks identical to the 1895 SBL 45/70 . Stainless and laminate with the long top rail. Great little rifle. I find it very mild on recoil but then again my go to rifles are all big bores. Had the barrel threaded and supressed by DPT. great little supressors those. Unless your barrel is free floated in the stock you will have POI change if barrel is resting on something. even using a sling on a rifle as a brace around your arm can effect impact point if barrel not floated. It really doesn't take much to throw it out. I always try and sight my rifles in the same way I intend to shoot it. Just to be sure.
and your POI will definately change with supressor fitted. It will also dampen down the recoil noticeably and make it nicer to shoot as well as a little quieter even with full power loads. But once fitted resight with supressor and do all your shooting with it on . Once you try it you won't want to shoot without it anyway....

Thanks Ftx. I have started to appreciate big bores myself. I checked the barrel of my .223 recently and i was taken aback at how small the bore looked.

Well it is only a 22 on steroid's @Coote. When I had my evil black ar15 I used 223 on goats and swapped out the bolt and magazine and used 22lr on possums and rabbits. Super accurate running 22 as well. And it was supressed. The 22 just shot lower but still straight. Just used a graduated scope reticle.

I agree. Funny how I never really thought much about this stuff before. I used to just grab a rifle and some ammo and go out hunting. Now I'm beginning to realise there is a science behind it all. I wonder what else I've been taking for granted.

some of them lever actions have ALWAYS been known to throw shots if you change pressure on forend.....two metal tubes with a band joining them out front unsupported is one reason...I learnt/was taught 40 years ago to never have barrel touching something hard or it would throw projectile away from aiming mark.... a stock that wobbles around like mad womans pissflaps and contacts barrel differently depending on your position must do similar things...why free floating and bedding work so well on rifles...its makes thing consistant...as Mimms has mentioned.....the same each time=bullet holes close to same place each time.

I saw you were lurking there Micky. I agree with what you say. I am also impressed with the subtle imagery that you used in your post.

Originally Posted by Coote

I saw you were lurking there Micky. I agree with what you say. I am also impressed with the subtle imagery that you used in your post.

Subtle imagery...!

The man is a poet.

For sure!! Without wanting to be sexist, a woman who has lost her marbles, and has an over-abundence of genitalia, would be worth taking for a hunt.
Maybe Mick has some experience to share??

a gentleman never tells...and I DONT either.