Idea for testing fit with shorter LOP

T

TheKlawMan

Moderator
I am pretty certain that many of the problems I am still having with my 870 after 4 months and over 700 rounds is the LOP. Still, as many of you know I am somewhat "frugal". When it comes time for a second gun, I will take Zippy13's suggestion and invest in a professional stock fitting. Meanwhile, I will cheap out.

As is, with the standard synthetic Remington stock, the LOP is 14". With that stock, it seems that I am constantly having to adjust the fit to my shoulder pocket in order to get a decent target picture. A friend even let me shoot with his very nice 1100 with a Monte Carlo stock to see how I liked it. It didn't seem to help, but its LOP was even greater than 14".

I have been doing mounting drills in the mirror without a recoil pad No pad effectively reduces my LOP to 13" and I get a much better mount. Before ordering another stock, as I am thinking that it may be time for a new gun in a few more months, I am thinking of shooting it without a recoil pad but taping a thin hard butt plate off an old Harrison & Richardon 1905 to the stock so as not to punch butt shaped holes in my chest.

See the pictures and tell me if this makes sense. I will use duct tape instead of the blue painter's tape.

Thoughts?
 

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Betcha' ain't gonna do another 700 rounds without a good pad.
Somewhere, and very recently, I ran across instructions on how to shorten a hollow synthetic stock and keep the recoil pad where it belongs.
I'll see if I can find it again.
 
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I probably posted a link to those instructions which I found on another board. The problem is if you shorten the stock you can't use the same pad If I indeed need an inch shorter stock, the youth stock is well worth the cost.
If you have some other instructions, I would sure like to see them.
 
Those are good instructions, g.willikers, asnd not he ones I had seen. Using the dremel for which inexpensive wheels for cutting practice are available is a good idea.

I think I'd rather save the original stock for my <5'10" son to whom I have promised the gun if I buy another.

If a shorter stock indeed is warranted, I will spend the $60. It cost me more than that for ammo, fees, and gas the last time I shot (when I almost certainly further imbedded bad habits into muscle memory.)
 
You can try that ...sure ....

But you have an angled comb on that gun ...and I think you're putting way too much focus on length of pull. If you shorten or lengthen that gun ...the comb moves in relation to your cheek ...so its going to change the point of impact a lot...

But if you want to fuss with length of pull ....do it at the pattern board. I wouldn't try and shoot that gun at targets and evaluate it. I'm not sure / at this point in your experience / you ought to be fussing with the length of pull at all ...until you've spent some time with an instructor.

The problem is ....none of us have seen you shoot ...so its really very difficult for us to evaluate your length of pull. I doubt the length of pull has much impact on your gun mount issues / I think that's more just "practice, practice, practice ..." .../ but I'd recommend you leave the length of pull alone until you can get with a good instructor who can help you ( and maybe give you 3 or 4 guns to test ...) with different lengths of pull.
 
As Jim said - more to it than LOP. Gun writer friend had Perazzi build him a gun for Argentina. He is about my height, so anything around 14.5 to 14.75 seems to work decently. This gun has 15.25" LOP - why? because of the way the pistol grip was designed. That allowed for a longer. and more comfortable, LOP to be built. The more relaxed the grip design, the longer you can go, the more pistol-like you can't. You might also have factors such as cast, drop, pitch and toe to consider
 
I hear you about the lessons and am going to try to see if my daughter can get herself to work so I can get out to Triple-B. Sending you a pm so as not to encumber this thread with the details of my travails.
 
Oneounce. I have often wondered about the grip and should ask about that. It seems to srong for my hands and that because of the grip and not the LOP I have to reach for the trigger. Easily cured if a wood stock. I am going to be patient and if you don't mind will cc you on the email to Jim.
 
Of all stock dimensions,LOP is least critical IMO. We can and do adjust by moving the support hand back and forth every time we mount a new shotgun.

Cast and drop are more crucial in siting the eyes where they need to be.

To the OP.....

Patterning is your best friend. One can determine where the gun is shooting vs where you are looking and rectify.

I've a hunch(Which may be way off because I haven't seen you shoot) a slight shim at the bottom of the receiver/stock will aid you....
 
Dave. While I don't see where the 870 is designed for shims, as some firearms are such as the Winchester SX3 I was thinking that I can make something up quite easily and in fact had already looked on line for a commercial product. As is I have some shim stock around here.

Thanks for the suggestions.
 
Patterning board

Patterning is your best friend. One can determine where the gun is shooting vs where you are looking and rectify.
Click to expand...

That is good advice. I am fortunate enough to live reasonably close to Orvis' Sandanonna facility in NY. As a retirement treat some years ago, my Mary arranged some instruction for me there. Included was a session at the patterning board with two men who knew what they were doing and a Try Gun.
I don't know how to adjust the Try Gun but the process from my end was simple and very graphic. You can do that part yourself.
They had a steel plate, painted white with a black spot in the middle, placed 16 yards from a shooting point. They handed me the Try Gun and told me to look at the spot and then to mount the gun and - without looking at the bead - point the gun at the spot and shoot. They repainted the plate and the spot after each shot and adjusted the Try Gun. By the time they were done, each shot that I took was centered on the black spot.
You could do some of this with a piece of cardboard, a couple of spray cans of paint, and your shotgun. At least you'd know if it's shooting where you look.

Pete
 
darlgael; What you wrote suggests to me that there are at least two ways of using an patterning board to determine pointing as opposed to patterning characteristics.

The only time I used one I carefully sighted down the rib to aim. The purpose being to know where the gun was shooting in regard to where it was aimed.

Anyone feel free to correct me if I am wrong, but what you describe seems as if the idea was to determine where your tri fit was pointing in comparison with where you looked, which I understand is what I am supposed to be doing as opposed to aiming at clays.

Although I will not be using a tri fit, I will take a lot of paper with me and try to discover both my POI when sighting to he POA, as well as the POI when looking at the the POA, if that makes sense. I might also give it a go with both one eye and two.
 
K-Man, I've used pieces of shotgun hulls, cardboard, matchbook covers and aluminum foil. I prefer foil.

Pete has it right. At 16 yards, the book says that moving the stock 1/16" moves POI one inch.
 
Thanks again Dave. I think the shims I have are .010" down to .002" but I can easily get some stuff at the Home Depot. Actually, tin cans make pretty could shim material. I did some googling and apparently any attempts to manufacture an 870 shim product has flopped, but it should be even simple enough that I can knock something together.

I wouldn't be surprised if the range's patterning board is set up at 16 yards, as it is just past the last trap house and the distance looked to be about the same as the front of the house to the front line.

Meanwhile I keep drilling in the mirror and think I may have gotten the proper mount. The pattern board may just confirm things.
 
Patterning Board

A "patterning" board when used to determine the pattern that a particular load gives you out of a particular gun with a particular choke is normally placed at 40 yards.
The board used for determining where a gun is shooting in relation to where you are looking is - as noted - at 16 yards.
Proper gun fit is what makes the gun shoot where you are looking.
There are a lot of people here who know more about it than I.
Pete (15.75" LOP, drop at comb 1.5", at heel 2.5", Cast 3/8"off, Pitch +4)
 
Okay. That makes sense. Also, I think I better beg, borrow, or buy a full choke to have a better idea where it is shooting. The tightest I have is a modified.
 
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Unless you cannot reach the trigger don't worry too much about LOP. If you are trying to determine point of aim, this has nothing to do with patterning, TAKE THE BEAD OFF YOUR GUN and follow the steps above. Remember your eye is the rear sight, so to raise the point of impact raise your eye, to lower it you must lower your eye. Unless your are extremely tall, with a Remington factory field stock, I doubt you will need to lower your eye. To raise it tape some 4x6 pieces of cardboard to the comb. If this works you can buy a neoprene sleeve with different inserts. You can adjust pitch with a quarter or two under the recoil pad then buy and grind to fit pitch plate from Midway. Pitch is fine tuning and not necessary for the beginner.
IMO you are worrying too much about gun fit. Close is good enough to start, and with only 700 rounds under your belt, that is where you are. Get your gun shooting where you look then go bust targets.

FWIW we had the South Carolina Youth Shooting Foundation State Sporting Clays Championship this past weekend. 386 shooters attended.The winning 3 man varsity squad missed a total of 12 targets out of 300. Their top shooter had a 99/100. All with stock Beretta 391's. Other than drop adjustment, they were as they came out of the box. A custom fit gun is nice, but not necessary.
 
LSnSC, Thanks for that. Cardboard and duct tape are my kind of mods. I also figure that anything can be made out of scrap lumber. I know a guy assisting a skeet coach, and the assistant was himself no slouch, built up his comb with automotive bondo to turn his stock into a Monte Carlo. I think the idea was that he could sand a bit off or add a bit as he adjusted it. It was ugly as hell but he could sure shoot.

Unless my gun is grossly off I won't be messing with shims at this point. (At least I will try to sit on my hands, as I love to tinker.) Anyhow, I have made some basic adjustments at home in how I have been mounting and placing my feet. Just following the Remington pamphlet on Trap. I have high hopes that a lot of my problems are going to go away. Nothing fancy but getting back to simple fundamentals.

And I am far from being very tall; just under 5'8" and 203#. My neck may be a little long.
 
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