POI Shift, My Old Nemesis!!!

[Tomiboy]

Do you have access to an indoor range? That can take the wind out of the equation. 

 

[bandg]

Trying to figure out POI changes with air rifles is a fool's errand. Check your zero before hunting if possible, otherwise, try to accept it as part of the sport. In my experience, some barrels need seasoning after cleaning to settle down, others change throughout the cycle to the next cleaning. It's probably the only aspect of precision AR shooting that I find as frustrating as rimfire. Rimfires will change POI with different ammo, even of the same velocity, or, different lots of the same ammo. But air rifles seem to do it for no reason.

I don't agree with the generality of this statement. It seems widely true but not always the case. It is one reason the Walther LGU I own is my go to gun for a first shot. It does not change POI noticeably from day to day. I have others that certainly do change POI noticeably and a few recent acquisitions that I don't know about yet (the Weihrauch HW44 I got recently has so far not shown much change from session to session but I don't have enough time with it to state that it "doesn't").

Yes, I have a couple that are relatively stable day-to-day as well, a Steyr Challenge Hunting (strange label for a single shot with no safety) and, so far, my Red Wolf. The consistency of the Steyr does not surprise me, offering typical Austrian simplicity, without a bunch of stuff complicating the barrel attachment system, just a bare, floating barrel. I suppose, given the light and relatively slow projectile, we should expect POI variations with significant weather changes. In other cases, I'm sure there is a reason for every POI change, but I sometimes can't find it. As a class, I have found air rifles to be a finicky bunch, as compared to their metallic cartridge cousins, but there are exceptions. If I remove the suppressor from my Brocock Bantam for transport, or to put on another rifle, when I attach it back on the Bantam I can expect a POI change, sometimes substantial. The Red Wolf, which uses a similar shroud arrangement remains on zero after such shifting around. Of course, none of this matters much for shooting targets or bouncing around cans or bottle caps, since it takes only a few minutes to check the zero. But, it can be problematic in a hunting scenario.

Agree completely with that. Hunting situations where a "warm up" is not readily done or a quick shot at a pest would seem to be the most critical situation for needing an accurate cold bore shot for most people. From my reading it is also something that military snipers work on to a great degree-knowing where the first cold bore shot will go. Air rifles do present a lot of variables in spring or gas ram performance related to physical conditions of the day or PCP air cylinder changes. They also seem to have relatively thin and soft barrels which might be more influenced by any change in harmonics or pressure on the barrel. So finicky in general, yes. But some seem to be much better than others in that regard.



I wonder how SSP and MSP guns might compare to springers/gas rams/PCP in this regard? MIght be more stable?

 

[tor47]

I have a .22 fx crown which had shifting POI. In my case it turned out to be the barrel needing cleaning regulary, as it fouled up with lead fast. Cleaning the barrel, and lubing the pellets seems so far to get POI stable for me.