Interesting video on POI shifts from various possitions

[Religious Shooter]

True, but for irons, the front sight does move. When using iron sights you're really lining up 4 things: Your eye, rear sight, front sight and target. If you rest or torque the barrel on something, the front sight follows it because it's attached so you're just lining everything up along a diffrent path.

now imagine you had a rifle with a sling attached to the barrel or you're resting and putting pressure on the barrel BUT the front sight is on the end of a FF rail. The sights would remain in the same place but the barrel would be flexed in a diffrent direction. If you have a AR with a FF rail go see for yourself. You can put pressure on the barrel and actually see the barrel flex and the FF rail stay pretty much in the same spot.

I know it will move. I don't need to do it to know what it will do. It's common sense.

What I was questioning was you assertion that the guy didn't have a shift with the A2 because of the front sight on the barrel. I guess well just have to disagree on that.

[George]

Geoff, this got me to thinking about your prone method of monopoding off the magazine AND pushing down and back on the FF rail. I wonder if that gives any flex to the system. I'll have to test it at 200 and see what comes out. For long range stages you're almost always braced diffrent: Prone, sitting, rooftop, through a window.... I'll have to test myself with my rifle to see if I get any shift with the diffrent positions and pressures on my rifle.

Not that I have found with either of my competition rifles with FF HG's. I have done group shooting and zeroing at 200 yards with bipod using neutral hold force and mono-podded with lots' torque on the rifle. Both result in pretty much the same POI and yield similar group sizes. Probably be able to see some diff at 350+ but I have not tested this beyond 200. The real trick here IMHO is to do whatever you do to the rifle consistently

BTW, I don't pull back on the HG with weak hand when I mono-pod, just down force like I am trying the bend the rifle in half over the mag. I push the hand guard away and try to "stretch" the rifle when I shoot offhand. I only pull back using the pistol grip to lock the butt-stock into my shoulder pocket (I do this in all positions)

[jaredr]

are y'all seeing something i'm not? cuz i'm seeing a guy shoot a fairly good group from prone supported, then a decent group prone off the mag and the same thing from prone + elbows, and then a crappy stringing really high group (i use group loosely here) when he's torqueing the barrel UP. i'm not really seeing anything we don't already know here. i shoot tighter groups when i'm bagged up vs. free hand, and we all use FF handguards and dont rest the barrel on objects because of the POI shift. DUH!

maybe i'm missing something obvious but I came away with much the same impression.

first group - reasonably tight, what I would expect from shooting prone with a support under my free-float handguard (appears that optic has been dialed in for this distance as POA = POI)

second group - ok, what you would expect from monopodding off the magwell.

third group - tells us nothing about the rifle, it's being fired unsupported

fourth group - tells us what we all know, resting the rifle on the barrel changes where the bullets end up.

feel like i'm looking for the picture of jesus in the pizza here - no hidden lessons or complicated messages I can see here

[Jesse Tischauser]

If you are still subscribed to this thread you belong on M4carbine or ARFCOM general discussion threads not on this forum, thus Is entry level stuff guys come on.

[George]

If you are still subscribed to this thread you belong on M4carbine or ARFCOM general discussion threads not on this forum, thus Is entry level stuff guys come on.

Ayup, eggs-ackerly why I am not speaking to the video in question here as there is nothing to question or answer there

[jaredr]

whew, for a minute there i thought i wasn't snotty enough to look down my nose at the OP and deride his questions along with the rest of us

all due respect, i'd say the last few responses are closer to what i would expect from arfcom then here

edited to add: i'll stay subscribed to this thread for the same reason I read most of this forum - there's still i might learn something...

Edited December 27, 2011 by jaredr