FX Impact M3 lowest scope mount options?

[Huncowboy]

I have the M3 and I was wondering if there is a way to remove the top picatinny rail (it looks like two screw are holding it) and mount some 3rd party rail that is low profile, so the scope can get a good half an inch closer to the barrel. Has any of you guys done this? If so please post some pictures and links. Thanks!

 

[JaceSpace1369]

I have the M3 and I was wondering if there is a way to remove the top picatinny rail (it looks like two screw are holding it) and mount some 3rd party rail that is low profile, so the scope can get a good half an inch closer to the barrel. Has any of you guys done this? If so please post some pictures and links. Thanks!

I believe you would need a custom rail made for that.

 

[Spartan]

Good luck. Interested to hear about solutions. Sometimes I feel like I'm now in the vast minority for wanting to keep the scope as close to the barrel as possible for better holdovers. The trend these days seem to be to mount scopes cartoonishly high, which does have benefits for actual tactical reasons (e.g., the people who are actually needing to kick in doors), and for extreme long range shooting, but mostly drawbacks for hunting and typical bench shooting. But people want what's looks cool, so that's what sells nowadays.

 

[Smok3y]

I have the M3 and I was wondering if there is a way to remove the top picatinny rail (it looks like two screw are holding it) and mount some 3rd party rail that is low profile, so the scope can get a good half an inch closer to the barrel. Has any of you guys done this? If so please post some pictures and links. Thanks!

I haven’t seen many go that low. But there are some aftermarket options.
This guy had a good list:

FX impact top rails!

So every man and their dog knows all about the FX impact and the fact it lends itself so well to the the aftermarket and all the accessories that exist and have turned a unassuming gun into a "platform" Well whilst watching a couple of YouTube videos I came across yet another company getting in...

airgunforums.co.uk

And here is a cheaper option from UA, but not sure how much lower that will get you.

Hardy Custom - Top FX Impact Extended Rail (20MOA)

Hardy Custom - Top FX Impact Extended Rail (20MOA)

utahairguns.com

Good luck. Interested to hear about solutions. Sometimes I feel like I'm now in the vast minority for wanting to keep the scope as close to the barrel as possible for better holdovers. The trend these days seem to be to mount scopes cartoonishly high, which does have benefits for actual tactical reasons (e.g., the people who are actually needing to kick in doors), and for extreme long range shooting, but mostly drawbacks for hunting and typical bench shooting. But people want what's looks cool, so that's what sells nowadays.

I don’t think it is about being cool. These rifles are flat top, so allow no room for the objective to drop down. You have to get it up in the air for the large scopes nowadays.
I used to want my scopes low, until I tried an Impact mounted high. Most comfortable shooting from a bench I have ever had, and now I go high. I like it for comfort and doesn’t affect me in any way, unless you start changing positions, and then it can get more difficult, like in prone. But bench is great high.

 

[Swish]

You can buy sections of picatinny rails in different heights and lengths on line fairly cheap. You just have to drill and countersink 3 holes. My MK2 Impact has a custom low profile rail on it.

I run adjustable scope bases and Absolute MOA Digital Readout kits for ELR shooting. The low profile rail reduces scope height and some weight.

 

[Huncowboy]

Thanks for all the replies. The gigarail is definitely lower but not sure if I want the extra stuff. More weight.

 

[Smok3y]

Thanks for all the replies. The gigarail is definitely lower but not sure if I want the extra stuff. More weight.

For the price of that Hardy at UA, I would call/email them and ask them for a measurement. With RMAC this week, don’t expect a fast response.

 

[JungleShooter]

I have the M3 and I was wondering if there is a way to remove the top picatinny rail (it looks like two screw are holding it) and mount some 3rd party rail that is low profile, so the scope can get a good half an inch closer to the barrel. Has any of you guys done this? If so please post some pictures and links. Thanks!

Krisztian,

do you want to mount your scope LOW because you are you trying to change your point blank range (PBR)?

➠ I have been on the mount-the-scope-LOW train for several years now.
I even have made up a table for adjustable scope mounts with an emphasis to identifying the lowest possible mounting options (30mm).
If you're interested, I'll post the table.


However....
I have gotten off that train lately.
I sat down and did some ballistic calculations with ChairGun — and realized that mounting my scope half an inch lower does not make such a big difference to my point blank range (PBR).


Here's one example:
.22cal
30FPE
15.89gr JSB dome

4 scope heights:
from 1.57" (4.0cm) to 2.17" (5.5cm)

Killzone 1" (2.54cm) — so any hit 1/2" (1.27cm) below or above is fine.

The PBR's are as follows:
▪red = 1.57" (4.0cm) ➠ PBR = 9-47y
▪blue = 1.77" (4.5cm) ➠ PBR = 10-49y
▪green = 1.97" (5.0cm) ➠ PBR = 12-49y
▪purple = 2.17" (5.5cm) ➠ PBR = 13-50y

Cf. the graph below.


(I have a few other calibers and power settings made up, if you're interested.)

Matthias

 

[bigHUN]

Based on my experience if you want to go with lower scope mount on Impacts you will get more aggressive cheek weld. Unless you sitting and aiming behind the gun stock, like with dedicated BR guns = rail guns.
How good or bad that will be for your shooting accuracy also posture is up to you to figure that out.

 

[Huncowboy]

Krisztian,

do you want to mount your scope LOW because you are you trying to change your point blank range (PBR)?

➠ I have been on the mount-the-scope-LOW train for several years now.
I even have made up a table for adjustable scope mounts with an emphasis to identifying the lowest possible mounting options (30mm).
If you're interested, I'll post the table.


However....
I have gotten off that train lately.
I sat down and did some ballistic calculations with ChairGun — and realized that mounting my scope half an inch lower does not make such a big difference to my point blank range (PBR).


Here's one example:
.22cal
30FPE
15.89gr JSB dome

4 scope heights:
from 1.57" (4.0cm) to 2.17" (5.5cm)

Killzone 1" (2.54cm) — so any hit 1/2" (1.27cm) below or above is fine.

The PBR's are as follows:
▪red = 1.57" (4.0cm) ➠ PBR = 9-47y
▪blue = 1.77" (4.5cm) ➠ PBR = 10-49y
▪green = 1.97" (5.0cm) ➠ PBR = 12-49y
▪purple = 2.17" (5.5cm) ➠ PBR = 13-50y

Cf. the graph below.


(I have a few other calibers and power settings made up, if you're interested.)

Matthias

View attachment 481657

You are light years ahead of me. I am not even familiar with the point blank range term. But I will Google it.

I am shooting raccoons 15-20 yards from a slight elevation. So slightly aiming down. I am probably 3-4 feet above at 15 yards. So I zero to where their head is at that distance. I have noticed if they show up closer like 10 yards the rifle shoots significantly higher. So I figured this might have something to do with the scope sitting high. But I never investigated it.

 

[JungleShooter]

I am shooting raccoons 15-20 yards. [...] I have noticed if they show up closer like 10 yards the rifle shoots significantly higher. So I figured this might have something to do with the scope sitting high. But I never investigated it.

Yeah, you are absolutely right.

What gun and ammo are you shooting, at what power or velocity? I can run the ballistics for it so you can see some options for zeroing and scope mounting.

What is the maximum range that you would be shooting the racoons?

Cheers,
Matthias

 

[Huncowboy]

Yeah, you are absolutely right.

What gun and ammo are you shooting, at what power or velocity? I can run the ballistics for it so you can see some options for zeroing and scope mounting.

What is the maximum range that you would be shooting the racoons?

Cheers,
Matthias

Nice! Thank you in advance! I will take you up on this! We are on vacation for a few more days. Once I get home and assuming it is not raining nonstop (tropical summer here and a wet one) I will measure the distance and speeds again. It is not Raccoon season right now, I mean I don't see too many in the summer, at least not in my backyard, so the PCPs have been collecting dust for a few months now.

 

[JungleShooter]

Nice! Thank you in advance! I will take you up on this! We are on vacation for a few more days. Once I get home and assuming it is not raining nonstop (tropical summer here and a wet one) I will measure the distance and speeds again. It is not Raccoon season right now, I mean I don't see too many in the summer, at least not in my backyard, so the PCPs have been collecting dust for a few months now.

Hit me up whenever you're ready. Glad that my hours spent with ballistic calculators will benefit someone else, too.

Matthias

 

[Huncowboy]

Ok here it is. Sorry it took a while. Lots of rain here right now.

Shooting at 916-919 fps the Baracuda Hunter Extremes 18.52 gr by H&N. Distance is 15-20 yards. Absolute max is maybe 25 yards. Typical is right at 15. That is where the bait is. I am aiming down about 3 feet at 15 yards from the barrel.

 

[JungleShooter]

Ok here it is. Sorry it took a while. Lots of rain here right now.

Shooting at 916-919 fps the Baracuda Hunter Extremes 18.52 gr by H&N. Distance is 15-20 yards. Absolute max is maybe 25 yards. Typical is right at 15. That is where the bait is. I am aiming down about 3 feet at 15 yards from the barrel.

Krisztian,
and @bigHUN,
let's see:

OK, here are the base data:
Baracuda Hunter Extreme: 18.52gr
0.026 BC (yours might be slightly different)
MV = 917fps (34.6FPE)
Downward angle = 4⁰
Min. range: 15y
Max. range: 25y
Killzone: brain of racoons: est. 1.2" diameter*


Note that hitting a killzone (the area where a hit will be lethal) is more forgiving and gives more margin of error than hitting a bullseye the size of the caliber you're shooting.

Say, I estimate the diameter of a racoon brain to be 1.2" (no idea if I'm right).
If you hit the killzone a little high, or a little low, due to a range somewhat closer or farther away than your zero range — no problem! You'll hit the killzone in any case, so your shot will be lethal, and that's all that's needed. You don't get awarded X's when hunting....

The distances other than your zero distance at which you can aim at the center of the target — and still hit inside the killzone (up to 0.6" high and up to 0.6" low) — is called the point blank range (PBR).


Calculation of the PBR — using 4 different scope heights:
Using ChairGun Mobile

4 scope heights:
from 1.8" (4.6cm) to 2.4" (6.1cm)

The maximum achievable PBR's are as follows (as long as possible PBR's):
▪red = 1.8" (4.6cm) ➠ PBR = 9-50y
▪blue = 2.0" (5.1cm) ➠ PBR = 10-51y
▪green = 2.2" (5.6cm) ➠ PBR = 12-52y
▪purple = 2.4" (6.1cm) ➠ PBR = 13-53y

Cf. the graph below.

The (second) zero for each of these would call for the following, respectively:
44y (red), 45y, 46y, and 47y (for purple)


➠ This means that if your killzone is indeed 1.2" in diameter —
and you are an accurate shooter —
than your shots between 15y and 25y are well within your PBR and do not requiere an adjustment of the point of aim.
Indeed, your near zero is almost right at 15y for all those scope heights.

Matthias



*This I can only estimate, as we have no racoons in Peru.....
However, the larger the killzone, the more margin for error you have, and therefore the longer your point blank range (PBR) gets.

 

[Huncowboy]

Krisztian,
and @bigHUN,
let's see:

OK, here are the base data:
Baracuda Hunter Extreme: 18.52gr
0.026 BC (yours might be slightly different)
MV = 917fps (34.6FPE)
Downward angle = 4⁰
Min. range: 15y
Max. range: 25y
Killzone: brain of racoons: est. 1.2" diameter*


Note that hitting a killzone (the area where a hit will be lethal) is more forgiving and gives more margin of error than hitting a bullseye the size of the caliber you're shooting.

Say, I estimate the diameter of a racoon brain to be 1.2" (no idea if I'm right).
If you hit the killzone a little high, or a little low, due to a range somewhat closer or farther away than your zero range — no problem! You'll hit the killzone in any case, so your shot will be lethal, and that's all that's needed. You don't get awarded X's when hunting....

The distances other than your zero distance at which you can aim at the center of the target — and still hit inside the killzone (up to 0.6" high and up to 0.6" low) — is called the point blank range (PBR).


Calculation of the PBR — using 4 different scope heights:
Using ChairGun Mobile

4 scope heights:
from 1.8" (4.6cm) to 2.4" (6.1cm)

The maximum achievable PBR's are as follows (as long as possible PBR's):
▪red = 1.8" (4.6cm) ➠ PBR = 9-50y
▪blue = 2.0" (5.1cm) ➠ PBR = 10-51y
▪green = 2.2" (5.6cm) ➠ PBR = 12-52y
▪purple = 2.4" (6.1cm) ➠ PBR = 13-53y

Cf. the graph below.

The (second) zero for each of these would call for the following, respectively:
44y (red), 45y, 46y, and 47y (for purple)


➠ This means that if your killzone is indeed 1.2" in diameter —
and you are an accurate shooter —
than your shots between 15y and 25y are well within your PBR and do not requiere an adjustment of the point of aim.
Indeed, your near zero is almost right at 15y for all those scope heights.

Matthias



*This I can only estimate, as we have no racoons in Peru.....
However, the larger the killzone, the more margin for error you have, and therefore the longer your point blank range (PBR) gets.


View attachment 484645

Thanks for all this info! Scope height is distance of center of scope from barrel center? Right?

 

[MRaccurate]

Krisztian,
and @bigHUN,
let's see:

OK, here are the base data:
Baracuda Hunter Extreme: 18.52gr
0.026 BC (yours might be slightly different)
MV = 917fps (34.6FPE)
Downward angle = 4⁰
Min. range: 15y
Max. range: 25y
Killzone: brain of racoons: est. 1.2" diameter*


Note that hitting a killzone (the area where a hit will be lethal) is more forgiving and gives more margin of error than hitting a bullseye the size of the caliber you're shooting.

Say, I estimate the diameter of a racoon brain to be 1.2" (no idea if I'm right).
If you hit the killzone a little high, or a little low, due to a range somewhat closer or farther away than your zero range — no problem! You'll hit the killzone in any case, so your shot will be lethal, and that's all that's needed. You don't get awarded X's when hunting....

The distances other than your zero distance at which you can aim at the center of the target — and still hit inside the killzone (up to 0.6" high and up to 0.6" low) — is called the point blank range (PBR).


Calculation of the PBR — using 4 different scope heights:
Using ChairGun Mobile

4 scope heights:
from 1.8" (4.6cm) to 2.4" (6.1cm)

The maximum achievable PBR's are as follows (as long as possible PBR's):
▪red = 1.8" (4.6cm) ➠ PBR = 9-50y
▪blue = 2.0" (5.1cm) ➠ PBR = 10-51y
▪green = 2.2" (5.6cm) ➠ PBR = 12-52y
▪purple = 2.4" (6.1cm) ➠ PBR = 13-53y

Cf. the graph below.

The (second) zero for each of these would call for the following, respectively:
44y (red), 45y, 46y, and 47y (for purple)


➠ This means that if your killzone is indeed 1.2" in diameter —
and you are an accurate shooter —
than your shots between 15y and 25y are well within your PBR and do not requiere an adjustment of the point of aim.
Indeed, your near zero is almost right at 15y for all those scope heights.

Matthias



*This I can only estimate, as we have no racoons in Peru.....
However, the larger the killzone, the more margin for error you have, and therefore the longer your point blank range (PBR) gets.


View attachment 484645

Good to hear your thoughts again, Matthias. I've have not been on any blogs for about 1 1/2 yrs. I have been busy on another theory patent and developing better component designs for my first sights. You were one of the few that challenged me on theory in a good way. Look forward to more discussions in the future. The reason I'm chiming in is when I entered your data of 4 degrees at 25 yards, I get a variation of .01". Since I don't shoot over 50 yards, I have never entered degree data into any of my calculations. Is my calculation correct? Just for your information, based on our past conversations using your sight calculations for my sight, I would have zero hold of + .4"/-0.0" from 0 yards to 25 yards. This data would not apply to any other sight, but I thought you would be interested. I don't expect anyone else would understand this. It is amazing that there has been no interest from any manufactures about these capabilities. My sight is still not on the market, but I am still trying. Hope all is well in your life. Brad

 

[JungleShooter]

Thanks for all this info! Scope height is distance of center of scope from barrel center? Right?

Yes!

And there are several ways to measure scope height:

➊ With calipers, and that typically involves dividing the barrel/shroud diameter and the scope tube diameter by 2.

➋ The most precise way is to measure the height at the muzzle — the place were exterior ballistics start (and were our ballistic calculators start at).
You measure by shooting at a paper as close as possible to the muzzle, and measuring the distance between POA (point of aim) and POI (point of impact).

It's explained here:

Chairgun and “Scope Height”

I hear a lot of people complaining about the ballistic software Chairgun not being in line with their real world results. But in my field target rifle and scope combo’s it has improved to bei…

airgunaccuracy.wordpress.com

Cheers,
Matthias

 

[JungleShooter]

Good to hear your thoughts again, Matthias. I've have not been on any blogs for about 1 1/2 yrs. I have been busy on another theory patent and developing better component designs for my first sights. You were one of the few that challenged me on theory in a good way. Look forward to more discussions in the future. The reason I'm chiming in is when I entered your data of 4 degrees at 25 yards, I get a variation of .01". Since I don't shoot over 50 yards, I have never entered degree data into any of my calculations. Is my calculation correct? Just for your information, based on our past conversations using your sight calculations for my sight, I would have zero hold of + .4"/-0.0" from 0 yards to 25 yards. This data would not apply to any other sight, but I thought you would be interested. I don't expect anyone else would understand this. It is amazing that there has been no interest from any manufactures about these capabilities. My sight is still not on the market, but I am still trying. Hope all is well in your life.
Brad

Hey Brad,

glad you're back!!

Yeah, work or life circumstances can make us take a break from the forum....
I'm starting a new venture and I might have to cut down, too. (And this thread is not reflecting that....! )

● The difference that a 4⁰ down (or up) angle makes — especially at 25y — is so minute, it can be ignored.
● Now shooting out to 200y that angle might make more of a difference.
● Or shooting squirrles 75⁰ up in the trees at closer ranges — that makes a more significant difference in the point of aim.



➠ Keep up your work with your sights!
➠ And keep us on the forums in the loop — if we can help we will — eventually we all will benefit from R&D, innovation, mavericks, and those precious few who dare to think outside the box. More power to you, Brad!


Cheers,
Matthias