Muzzle devices and adjusted zero

[Lowdown3]

Various muzzle devices will affect the POI on a rifle. Depending on the type of barrel and various other factors these can be a little or a heckuva lot.

Had a ridiculously large POI shift on a muzzle device on an AK. However on this Savage bolt gun, the POI change was very little, about 2" at 200 yards. Was zeroing a new scope and noticed it.



At 500 yards I held at the 500 BDC bracket and it rang steel every time on a full size IPSC target.

[Lowdown3]

Being as it's not on there all the time, I will just adjust via holding when I use it versus zeroing specifically for it.

[RobertJ]

There are a lot of things the muzzle brake/comp./supressors affect. Point of aim/ point of impact is the first noticeable. It also affects "blow back" and timing of the bolt and bolt carrier.

The "muzzle device" of choice effects "pressure" which in turn affects everything else on gas system firearms. I mostly speak for the AR Platform but the AK as well. Thats why SBRs are finike, and why you will see a lot of SBRs with a Krink "Style" brake on them. This is to create more pressure (burn time,etc.) so you wont have any failures. The krinks are the "quick easy fix" you will see "pigtail" gas tubs on AR platform rifles to do the same thing as the krink brake. Others will open up the gas hole in the barrel to do this as well (Drill it larger).

In my experience the worst offenders for point of aim point point of impact are the #1 supressors. #2 longer "closed" styled muzzle devices, think Krink or a Spikes barking spider. All muzzle devices will change POI to some degree so test fire after changing something out, to see how it affects POA/PoI or if your firearm functions correctly.

Sorry for rambling

Watched a gentleman destroy a Brake shot off his rifle down range. It was!!! one of those pin on deals that tapco sold. He used the wrong cal. brake and shot a larger cal through it. Some minor injuries to the person next to him watching. some brass or metal spalling from incident.
Be careful out there

[Bill Foster]

Interesting subject. I started researching this subject after reading this and as RobertJ pointed out, I will stay away from the "pin-on" style. As I have a post-ban Mak-90, the "safe" install is to shave down the end of the barrel and then thread it for a comp. Has anyone seen this done?