inaccuracy with handguard mounted sight

[capx28]

so i have read that when you mount a red dot on the rail of the handguard or a bipod that it can cause inaccuracies due to (if i remember correctly) the barrel not being able to "whip" freely.
i tried mounting a red dot on my rifle in front of the carry handle which puts it on the handguard and even though the red dot was lined up with the irons the POI was off to the left. Even ignoring the red dot and focusing on the irons yielded the same result. Took the red dot off and BULLSEYE. So is it the endcap of the handguard that causes this? can i take the endcap off and solve this? I know i can get the tacticool stuff to change it but im not comfortable taking the barrel off and all that good stuff. Any thoughts would be appreciated.

 

[capx28]

oh and i also know i can go without a carry handle and i just might do that.
i just like to know all my options.

 

[Arik]

If the handguards are touching the barrel and you tighten something onto the handguards you are putting pressure where there was none thus the barrel will behave differently. You can put whatever you want on it you just have to sight it in that way

 

[capx28]

does simply removing the endcap of the handguard fix this?

 

[GhostMutt]

I think the only true way of negating hand guard flex is to replace the handguard to a free float handguard with T22's barrel nut. (No i have not and i also do not work for him )

Mounting any optics on the handguard i think is going to produce a slight shift, depending on how much pressure is placed on the grip but i think you have to really grip that mofo to produce drastic shift. Best to mount any and all optics (beside front sight post obviously) on the upper. I haver removed the endcap having read previously on this forum that it serves no purpose but can interfere with the flex issue. Plus i had to get my barrel wrench down there to tighten the barrel nut (a known issue with flyers)

 

[RedNeck Jim]

I think the only true way of negating hand guard flex is to replace the handguard to a free float handguard with T22's barrel nut. (No i have not and i also do not work for him )

Mounting any optics on the handguard i think is going to produce a slight shift, depending on how much pressure is placed on the grip but i think you have to really grip that mofo to produce drastic shift. Best to mount any and all optics (beside front sight post obviously) on the upper. I haver removed the endcap having read previously on this forum that it serves no purpose but can interfere with the flex issue. Plus i had to get my barrel wrench down there to tighten the barrel nut (a known issue with flyers)

Agree. I use Tacticool22's barrel nut wrench plus use his barrel nut so as to mount an aluminum AR handguard. I too removed the endcap when I still had my original handguard as it serves no purpose & as you say, gets in the way whenever you want to work on the barrel. I remove my barrel when I clean as it is soooo much easier plus I always know my barrel is tightened properly.

However the way I understand it, the 15-22 comes with a free float handguard. It is only held in place by the barrel nut. I wont argue that an aluminum handguard might flex less but even then, I wouldn't place any optic on a handguard. The receiver is rock solid and IMO that is where they need to go.

 

[Arik]

oh and i also know i can go without a carry handle and i just might do that.
i just like to know all my options.

I'm not familiar with the 15-22 so I don't know how it's set up. Generally AR handguards are semi free floating. You can buy free floating handguards for them. Don't know if it would fit the 15-22. Free float means no part of the handguards touch the barrel

 

[McE]

It's a 22lr. You're chasing the wrong problem if your first course of action is worrying about a free floated barrel.
Are you shooting off a rest? Are all of your shots with the red dot still grouping?

 

[Rob1]

I have to ask this as many have mentioned various points on the forum over the 18 months or so that I have been on it and since I purchased my 15-22 MOE.

Firstly, IF the "Flex" phenomenon is such a huge issue, why is the rifle supplied with irons ? be it MBUS or Post type such as in the Performance Centre version.

Secondly, after firing mine pretty regularly for the last 18 Months and having somewhere in the region of around 3.5 K of various types of ammo, with and without sound mod, on a Range free hand and rested, also out on open land long and short range target and plinking, fast firing and slow deliberate aimed shots, HOW are people HOLDING this thing to make it NOTICEABLY BEND or FLEX ?

I had some harsh comments said early on about my level of shooting competency and accuracy by a couple of local trolls, well I ask this in all seriousness, using a sling (MS3 Multi Point), as a steadying aid and holding the rifle free hand, I can HONESTLY say I have not noticed or felt and of the so named FLEX.

I can only therefore conclude that, some of you guys across the pond must be 10 feet tall, Bright Green and answer with a grunt to the name of Hulk.

Pics of Fore arm and biceps will surely follow to prove this point, as it has been said on the forum aplenty, if it isn't in a picture or a video, then it didn't happen.......

though even with pics and vids it can still be called in to question

Don't intend to offend ANYONE but wanted to ask the question, as I'm thinking that if people are holding and wrapping themselves that tight around what is in essence a PLASTIC rifle, then surely they MUST expect a little bend here and there followed by periods on inaccurate shooting and poor groups, notwithstanding poor ammo quality (when you can find it), cheap knock off sights, super expensive optics and pop up irons and of course the world renowned problem of a true (or not) free float barrel.

Just a curious Brit pond hopper trying to figure out what is actually the real problem.

Rob.

will standby for the incoming.....

 

[RedNeck Jim]

Just a curious Brit pond hopper trying to figure out what is actually the real problem.

Rob.

will standby for the incoming.....

I think you make valid points. You know, the handguard on the 15-22 is polymer but dang... it is thick. I really doubt anyone could easily flex it.

I'm curious if the actual issue is a loose barrel nut. There has been plenty of discussion here where folks have had that issue. Seems to me if the barrel nut is loose, that the handguard could therefore move, not flex, as the only thing holding the handguard is that nut.

 

[capx28]

I am new to rifles and this being my first. I have NOT taken a beginner rifle coarse so i am at no means an a knowlegable or experienced shooter. I was shooting with a red dot sight (sightmark ultra shot) mounted on the handguard in front of my carry handle.( I just wanted to see how a red dot was without changing and re zeroing everything). I zerod the red dot to line up with the irons. So i could see through the rear peep and the front post and had the red dot sitting right on top of the post. I was at an indoor 25yd range. Standing with my elbow resting on the shooters table and gripped on an AFG near the magwell. The POI was left about 2-3 inches. Grouped well but way left. Without adjusting anything i took the red dot off (QD mount) and POI was dead on again. Just thought some of these details might be pertinent
If the barrel nut was loos would i see inaccuracies with just the irons?
oh and ammo was Geco 40gr optimized for semi-autos (love this stuff by the way)

 

[GhostMutt]

Yep ^ agreed.

Mine was posting some shocking groups...got the tool, tightened the nut, no problems since.

I remember a while back, 25yrd offhand i once shot a perfect 100/100 now if i don't do that every single time....then it must be something wrong with the rifle. Never the operator.

Granted if you really grip that thing as Rob1 stated all David Banner style, then arrrrgggghhhhh. Surely you don't even need a rifle...Hulk bash, Hulk Smash. Silly plink, plink no interest mighty Hulk.

If your rifle is having weird flyers (not the Philadelphia version) then try first changing ammo, if it persists try the barrel nut tool, if they still persist, then...i don't know maybe your crown is damaged?
In essence the rifle unless damaged, when using decent ammo, will shoot where it is pointing (environmental factors taken into account) If you have issues, stick the gun in a bench vice and see what groups you get. When the operator, stance, grip, breathing, decision making, nerve impulse, muscle firing, trigger control and general state of being are taken out of the equation.
Remember, accurate shot placement is more about being a zen monk than John Rambo.
My pennies worth, for what its worth.

 

[GhostMutt]

I am new to rifles and this being my first. I have NOT taken a beginner rifle coarse so i am at no means an a knowlegable or experienced shooter. I was shooting with a red dot sight (sightmark ultra shot) mounted on the handguard in front of my carry handle.

Have you tried using just the red dot, that may be where the problem is? just a dodgy sight, might have taken a knock or something....i would zero the red dot alone, then add the irons an see what the results are. If the red dot reticle appears to the right of your irons then B I N G O was his name o.

 

[NJDevil72]

This is an AR pattern .22 rifle. You can get a pretty reasonable amount of accuracy but if you are looking for a precision rifle the M&P 15-22 is not what you want.

 

[nagantino]

The number of people reporting a loose barrel nut is amazing. Really! This is a basic piece of the rifles construction so it's hard to believe the casual reference to its continued reporting as a problem.

 

[capx28]

i realize the limitations of the 15-22's accuracy abilities NJ Devil. It is plenty accurate for me and i love it. I was simply wondering why when something is clamped to the handguard the POI moved left ( still grouped normal, just moved left) then when removed POI moved back to normal.
Thanks ghost mutt! sounds like one of those fancy barrel tools would be good to have on hand.
Thanks for all your input guys as always it is much appreciated!

Oh and i have decided to go with the Primary Arms 2.5X compact scope and mount it on the carry handle

 

[F75gunslinger]

I don't own a 15-22, but have built a couple AR's. If the barrel nut is not tight it won't hold a constant zero. And just like any other rifle,any pressure on the barrel will interfere with barrel harmonics.So an added sight on the handguard puts pressure on the barrel via the endcap, and the zero will move. Best advice is to mount what you want to mount, then re-zero it with the latest addition.

 

[GhostMutt]

Thanks ghost mutt! sounds like one of those fancy barrel tools would be good to have on hand.

The Tacticool tool is great and gives peace of mind regarding the nut vibrating loose and its just nice to have a dedicated tool should you wish to do work on the handguard at a later date. You would notice large inaccuracies if the nut were loose though, your fliers would be a few inches away from your main groupings.

Just remember any work done on the rifle you must be careful not to twist the barrel in the upper. Secure the barrel in a vice and not the handguard or upper. Tacticool also does vice jaws, should you need them.

I dont think that you have a loose barrel nut though if your groupings are tight. The POI shift is probably due to the sight placement (on the handguard) as stated earlier. But i would remove everything and have just the red dot on, zero that then put the carry handle and front post back on and see what happens then....explore the variables. If there is one thing that i have learnt is that cheap and cloned optics are just that. I have one on mine (45 angle mounted TrijiCON rmr) and it is actually pretty good for a minute of tin can at 25 yards, but my primary optic is in the $500 range.

In regards glass and quality you do get what you pay for with optics.
But all that aside.....put whatever you want on your rifle and have good safe FUN.

Hope you get your issue sorted out with the new scope. Don't give up on the sightmark though, its nice to have options

 

[capx28]

im going to keep the sightmark and might later use it with some flip ups instead of the carry handle with the option of a magnifier also. but i do like the idea of being able to have the carry handle and the magnified scope on top of it. I'll stay away from anything mounted on the handguard. The way i see it is: now i will have 2 sights with more options and with 2 sight options it just makes sense to get another rifle
please correct me if im wrong