Holosun 407k x2 zeroing question

[HDTX]

Hi all, recently tried out a 43x w/Holosun 407k x2 I was considering picking up and ran out of elevation on the dial. Wound up turning the dial all the way up to the point it felt like it was just spinning and wouldn't come up any further than shooting right at 4" low at 7yds. Wasn't sure if that might be a common problem or issue w/red dots in general or something specific to that particular red dot? Pretty new to shooting a pistol w/a red dot so not sure if theres something I may have overlooked or if red dot might be potentially damaged in some way? Thanks!

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[VinnieBoomBah]

Which pistol and how's it mounted to the pistol? IIRC there were some S&W Shields that had the mill cut sloped down

 

[HDTX]

Glock 43x mos, plate is DPP marked GL-H07k and as far as I know was factory plate.

 

[VinnieBoomBah]

If you haven't already I would pull everything apart, dry fit it and check to make sure it sits flush and doesn't wiggle and reassemble it all again. If you get the same results you can shim the underside of the mounting plate between the plate and slide If that doesn't help I would consider returning the sight for a warranty check out

 

[HDTX]

Right on, thanks!

 

[titus123]

Is the plate required, or can you mount directly to the slide? Also, what weight ammunition are you running? And at what distance are you attempting to sight in at? Typically in LE, we sight our RDS at 10 yards which gives us a MPBR of around 60 yards.

 

[HDTX]

Unsure on mounting w/out plate but worth a shot. 115gr @7yds but that was just first outing with it.

 

[titus123]

Unsure on mounting w/out plate but worth a shot. 115gr @7yds but that was just first outing with it.

At 7 yards you'll be hitting 3 inches lower than point of aim. At 10 yards, you'll gain those 3" in elevation. Your sight has approximately 50 moa of adjustment range (25 up/25 down) so either you have a bad optic, or it could possibly need re-centered ( could possibly have left the factory un-centered and was too close to the top of your elevation range).

 

[Koda]

Had the same problem with a different optic, some of the blue loctite oozed under the optic when assembled.... or some other minute debris got in there.
Disassembled , cleaned all surfaces, reassembled and it zeroed easy in the center of its range.

Ive heard that its really bad to adjust a micro red dot optic adjuster to its limit as they dont really have room in there to add a good hard stop feature.

 

[PiratePast40]

When you get it cleaned and re-assembled, might want to start out at least 15 yards away. Will be much easier when you bring it in closer.

 

[HDTX]

Right on, thanks y'all!

 

[Char77]

Hi all, recently tried out a 43x w/Holosun 407k x2 I was considering picking up and ran out of elevation on the dial. Wound up turning the dial all the way up to the point it felt like it was just spinning and wouldn't come up any further than shooting right at 4" low at 7yds. Wasn't sure if that might be a common problem or issue w/red dots in general or something specific to that particular red dot? Pretty new to shooting a pistol w/a red dot so not sure if theres something I may have overlooked or if red dot might be potentially damaged in some way? Thanks!

When you adjusted it "up" did you rotate the dial counterclockwise like how it's labeled or did you rotate it so the dot moved up in the window relative to the iron sights? How low was it shooting before making adjustments?

Is the plate required, or can you mount directly to the slide? Also, what weight ammunition are you running? And at what distance are you attempting to sight in at? Typically in LE, we sight our RDS at 10 yards which gives us a MPBR of around 60 yards.

The plate should be required unless the lugs on the slide are removed/shortened. The slide is RMSc but the dot is Modified RMSc; the opposite situation would fit without a plate.

At 7 yards you'll be hitting 3 inches lower than point of aim. At 10 yards, you'll gain those 3" in elevation. Your sight has approximately 50 moa of adjustment range (25 up/25 down) so either you have a bad optic, or it could possibly need re-centered ( could possibly have left the factory un-centered and was too close to the top of your elevation range).

Maybe I'm misunderstanding but I don't think it's possible to be 3" low at 7 yards and on at 10 yards unless the bullet is doing crazy things or the dot is about 10" above the barrel.


If it really is shooting low and the dot isn't broken there are 1 degree shim plates. 4" at 7 yards happens to be about 57 MOA so that should fix it if nothing else does.

 

[HDTX]

When you adjusted it "up" did you rotate the dial counterclockwise like how it's labeled or did you rotate it so the dot moved up in the window relative to the iron sights? How low was it shooting before making adjustments?


The plate should be required unless the lugs on the slide are removed/shortened. The slide is RMSc but the dot is Modified RMSc; the opposite situation would fit without a plate.


Maybe I'm misunderstanding but I don't think it's possible to be 3" low at 7 yards and on at 10 yards unless the bullet is doing crazy things or the dot is about 10" above the barrel.
View attachment 2221420

If it really is shooting low and the dot isn't broken there are 1 degree shim plates. 4" at 7 yards happens to be about 57 MOA so that should fix it if nothing else does.

I was turning the dial on the optic counter clockwise, in direction of arrow, and it was bringing the strike of the round up but after a certain point the dial would still click (although clicks felt gritty at that point) and wouldn't go any higher than than 4" low @7yds. There was a plate under optic but unsure of size/footprint (I'm new to pistol w/red dot) Getting it on a trade and its possible he may have gotten wrong plate or may still need to add shim as well or yeah, perhaps optic could be defective as well.

 

[titus123]

When you adjusted it "up" did you rotate the dial counterclockwise like how it's labeled or did you rotate it so the dot moved up in the window relative to the iron sights? How low was it shooting before making adjustments?


The plate should be required unless the lugs on the slide are removed/shortened. The slide is RMSc but the dot is Modified RMSc; the opposite situation would fit without a plate.


Maybe I'm misunderstanding but I don't think it's possible to be 3" low at 7 yards and on at 10 yards unless the bullet is doing crazy things or the dot is about 10" above the barrel.
View attachment 2221420

If it really is shooting low and the dot isn't broken there are 1 degree shim plates. 4" at 7 yards happens to be about 57 MOA so that should fix it if nothing else does.

Your bullet leaves the muzzle drops slightly, then rises it is a parabolic arc. The bullet doesn't shoot straight out of your barrel. The general rule is that a bullet fired from 7 yards will drop 3". Your mileage may vary, but in my profession we tend to sight our RDS in at 10-15 yards in case we need to take a t-zone shot out to 25 yards with our side arms.

 

[HDTX]

Your bullet leaves the muzzle drops slightly, then rises it is a parabolic arc. The bullet doesn't shoot straight out of your barrel. The general rule is that a bullet fired from 7 yards will drop 3". Your mileage may vary, but in my profession we tend to sight our RDS in at 10-15 yards in case we need to take a t-zone shot out to 25 yards with our side arms.

Right on, so equipment may be fine then, mightve just been the way I was using it. Thanks for the info!

 

[Camelfilter]

...the general rule is a bullet fired from 7 yards will drop 3"...

That doesn't make sense.

 

[VinnieBoomBah]

That doesn't make sense.

Gyrojet?

 

[1775usmc]

That doesn't make sense.

Yea…..

3 inches of drop in 7 yards….. am I understanding that statement correctly? From the point the bullet leaves the barrel to the 7 yard marker it drops 3 inches?

 

[VinnieBoomBah]

Yea…..

3 inches of drop in 7 yards…..

In my defense I'm not 18 any more

 

[Camelfilter]

Yea…..

3 inches of drop in 7 yards….. am I understanding that statement correctly? From the point the bullet leaves the barrel to the 7 yard marker it drops 3 inches?

Only thing that could be - maybe that poster is thinking of height over bore for carbine/rifle?

But this discussion isn't about carbine/rifle, & that poster didn't mention height over bore. He wrote bullet drop.

Which is pretty nonsensical...