HK MP5 A4 (in)accuracy

[cmmg warrior]

I have a question for my fellow rim fire shooters. I have just purchased a new HK MP5 A4, its the one with the 12 and a half inch barrel. The first round I put through it was about 3 inches low and about 2 inches right, bearing in mind this was from only about 5 meters, I was a little concerned. Ah well I thought perhaps I need to move the rear sight left a couple of notches.
I tried 2 clicks, no change, so I moved it all the way left, it still seems to shoot right at 5 meters but more so at 20 meters. In fact it shoots about 4+ inches right at that distance. Oh and I lowered the rear sight to its lowest position and it still shoots low.
My CMMG AR in .22lr shoots a pretty tight group right out to 50+ meters with a carry handle iron sight or red dot optic. So why is the MP5 so inaccurate, I thought HK were using a match grade barrel in these things.
I was going to just fit a red dot optic and zero that in but if the inaccuracy is compounded at greater distances then it's never going to zero.
What does every body else find with theirs? The MP5 looks the business but its going to end up left in the safe if its not rewarding to shoot.
I'm thinking of returning it as I've an idea that its faulty. Maybe I should ask the dealer I got it from to try it and see what they find. Its a real ball ache to return firearms as I guess I may end up needing a variation to get it changed.

Any advise/information from HK MP5 owners about their experiences would be much appreciated.

[cmmg warrior]

Thought I'd add some photos to show some target results from both the AR and the MP5

Firstly the MP5 then the AR.... wtfwtf

[Chuck]

My GSG MP5 with a C-More sight fitted.

The iron sights were pretty useless, way low and left.

[DanTheMan]

Oh and I lowered the rear sight to its lowest position and it still shoots low.

You need to raise the rear sight to move the point of impact up, not lower it.

[Sandgroper]

You need to raise the rear sight to move the point of impact up, not lower it.

Agree with Dan.

From http://jacobsonsguncenter.com/adjusting-iron-sights/

There seems to be some confusion in how you correctly move the iron sights on a gun that is not shooting where you want it to hit. Here is how to do it:

Adjust the rear sight in the direction that you want the bullet group to move. In other words, if the gun is shooting to the left of where you are aiming, you will want to move the bullet group to the right. Move the rear sight to the right and your group will follow. The same applies to any direction. Move the rear sight higher and the gun puts its bullets higher. Move the rear sight down and the group moves down. Move the sight left and the bullets move left. This rule is universal and applies to all rifles, handguns, and slug shotguns. The rule to remember is this: The bullet group follows the movement of the rear sight.

It's how I was taught.

[WelshShooter]

Have you tried different brands of ammo? I've had ammo that groups a few inches out compared to another brand.

[cmmg warrior]

I have tried Aguila HV and got the same results.

I always understood that this is the correct way to adjust rear sights

"Moving the sight left, moves P.O.I. left
Moving the sight right, moves P.O.I. right"

but this sight is as far left as it can possibly go and these are the results I got today at 20 yards, but I can't see that it can ever fire to point of aim using the iron sights on it....that seems a bit odd to me. I know I could put a red dot optic on it but surely a gun should be able to group pretty closely to point of aim over short distances using basic iron sights?

Should it go back? even if I just ask them to test it to see how well they can do with it, because judging by todays performance I'm convinced its faulty.

There is one thing for sure....it is consistently bad...

[nickb834]

I had the exact same model as you and had a fault where it constantly shot low.

It went back to the importer, and then back to HK where they ascertained that the faux front sight block (that looks like it's pressed on but is a cast part) had a defect that whereby the front edge wasn't perpendicular to the barrel, such that when the muzzle was tightened up - it pulled the barrel down in it's sleeve.

If you have a bore sighter - the laser kind, stick it the barrel and slacken the muzzle off - you'll see poi jump a fair bit IF you have the same problem as I had.

The good news is - my replacement one is much better, not as accurate as my AR but for a 12 inch barrel - it'll do, especially as it's ultra reliable and feeds and fires anything.

I wonder if you ended up with my old one repaired ;-)

[nickb834]

Also - its no match grade barrel - take the muzzle off and you'll see what I mean - it's about as thick as a telescopic car aerial or a McDonalds straw! (exaggerating but you get the point)

That said, I shoot mini rifle comps with it and it'll do inch groups at 25 yards offhand - IIRC the last time I shot a target for a decent group at 25 yards I think I got 8 inside the 10 ring and 2 just out - so say inch to inch and a half at 25 yards?

It's the wrong tool for the job if you want tight groups - knocking plates down, or hitting the A section on the coffin shape targets at 25 yards - then yeah fine, but otherwise there's better tools for the job.

[cmmg warrior]

It's the wrong tool for the job if you want tight groups - knocking plates down, or hitting the A section on the coffin shape targets at 25 yards - then yeah fine, but otherwise there's better tools for the job.[/quote]


Haha, yes I realise its no CZ but a fun gun is meant to be fun...and this isn't..:(
I'd like to be able to at least get 10/10 rounds on an A4 piece of paper at 20 yards, and with this it seems impossible.
Perhaps I have ended up with your old one...