drop at heel or comb height

[bigman]

Been shooting my 101 awhile now and seem to shoot high iv managed to adjust to that an shoot it ok , when i check my mount etc in the mirror my eye does sit rather high above the rib and after reading up on sight pictures and what your ment to see i do see the whole rib from slightly above ,

im larger that average fella very broad shoulders 6ft 7in, is it drop at the heel or comb lower i need to lower the poi ,

 

Cheers

[Gordon R]

Lower the comb.

[bigman]

Do they just remove wood from the stock?

[point and shoot]

lowering the drop at heel will automatically lower your eye position to the comb. I had the same trouble with my benelli M2 and finally sorted it with extra shims. It now shoots to my point of aim with a sighting flat along the rib.

[Gordon R]

Fairly simple with an auto with adjustment shims.

 

Not so easy on an O/U. You can get out the sander and take off the excess - be careful - take small amounts at a time, as it's easier to remove than put back.

[bigman]

Not something id dare do myself , not the best with wood work ill have to run it in the shop somtime and get a quote bet it not going to be cheap

[clayman]

Too low is always a problem - stretched back neck muscles leads to head lifting at the moment of fire, bead switch focusing happens when targets are viewed through the bead rather than over it. Clear sight of the rib means this is used as the pointing device in the periphery vision. While the ideal is about 3mm high for the pupil of the eye at the back of the rib, being higher is not a major problem. The effect is that the gun shoots high, but the amount is negligible. Even 10mm high only lifts the pattern 100mm ( 4") for every 10m of range - ie a 1/2" high comb setting lifts the pattern centre a bit over a foot at 30yds. The advantages of clear sight from a high comb setting outweigh any disadvantage in pattern placement and if you are correclt sighting the target over the bead anyway, the pattern displacement is less anyway. A pattern rising slightly to meet a target in full view is a good set up. Find out what the centre of aim is with the current set up height by using a pattern plate, then decide if you need to lower and if so by how much."

[JohnfromUK]

Too low is always a problem - stretched back neck muscles leads to head lifting at the moment of fire, bead switch focusing happens when targets are viewed through the bead rather than over it. Clear sight of the rib means this is used as the pointing device in the periphery vision. While the ideal is about 3mm high for the pupil of the eye at the back of the rib, being higher is not a major problem. The effect is that the gun shoots high, but the amount is negligible. Even 10mm high only lifts the pattern 100mm ( 4") for every 10m of range - ie a 1/2" high comb setting lifts the pattern centre a bit over a foot at 30yds. The advantages of clear sight from a high comb setting outweigh any disadvantage in pattern placement and if you are correclt sighting the target over the bead anyway, the pattern displacement is less anyway. A pattern rising slightly to meet a target in full view is a good set up. Find out what the centre of aim is with the current set up height by using a pattern plate, then decide if you need to lower and if so by how much."

Good advice - and many don't appreciate these figures

[bigman]

Good advice - and many don't appreciate these figures

Yes thank you for that bit of info it sank in well only trouble im having is im switching between 2 guns at the moment and its playing havoc, one shoots high the other low teach me to mess around with more than one gun

[clayman]

one shoots high the other low

 

Something odd in this, as theoretically a shotgun should never shoot low - different story with rifles etc, but:

 

If your eye is high on the rib from the comb, the gun shoots 1cm high for every 1mm of eye height at 10m

If the eye is too low, one of the following happens:

 

The shooting eye is blanked by the back of the action so the off-eye takes over and the result ( for a R/H shooter) is the gun shoots around 70cm to the left of apparent aim - about 2m at 30m creating a full pattern miss.

 

or:

 

In order to see you lift your head as you try to observe the forward allowance, creating a high pattern as the head bobs of the comb to see.

 

If you think about it, a shotgun could only shoot low if the rib tapered from the action up to a high end at the muzzle, and no gun ever has such a rib - they are either flat or they deliberately taper down to the muzzle as many guns, particularly game ones, are specifically set up to throw the shot-load above the rib line of sight. This suits driven game where such a set up lifts the pattern towards the head of an incoming bird so you kill without destroying the breast for the pot. Trap guns are also often set this way too ( see the skeleton Kreigoff K-80 high taper ribs) so that you can shoot at a rising target on its directional line and the shot goes up in its travel time by the same amount the target rises. Flat shooting guns need to "blot" targets shot trap style, and loosing sight of a target is never a good thing.

Sounds from what you are saying that there are compound set-up problems, which may not just be the gun, stance / mounts / eyes all have a bearing on shot load delivery, and if there are problems with any of these, even if the gun technically fits, if its not mounted correctly and technique has issues, the gun can end up shooting all over the place,

Edited December 15, 2012 by clayman

[seeker]

myth buster strikes again ... But that's what a good coach does

Thanks for the good write up

Edited December 16, 2012 by seeker

[clayman]

myth buster strikes again ...

 

perhaps I should change my handle on here..

 

myth buster..... hmmmmmmm............

[EdSolomons]

Post has been answered above- follow that you won't be far wrong. Higher is better.

[bigman]

Thanks for taking the time to post that ,great bit of info im still learning everytime i shoot maybe its not that the other gun shoots low just alot lower than the other that shoots high , think that makes sense , just need to get my finger out and get to work on a patern plate at different ranges and really see whats happening ,

i have shot both guns at paper at 30y the 101 pattern bottom edge sits on top of the rib this is with fixed choke imp mod, bottom barrel ,

[coyotemaster]

 

I am just curious with your obvious size you must have longer arms and am wondering if lengthening the stock would not benefit your plight? The farther down the stock you are the more drop there is. If the gun fit is fantastic then you wouldn't be asking any questions. I shoot higher with a shortened stock and lower with a longer stock---kind of like the 3 bears you need one that is just right. Just a bit makes a huge difference in impact and can be done with spacers or a thicker recoil pad or just the addition of a pad if none exists.