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Old October 24, 2001, 02:46 PM   #1
ATTICUS
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Why so high? Rem 870 question

I finally got around to shooting some slugs and buckshot through my 870 project gun. I used the bead sighted riot barrel and a box of Winchester slugs (silver box cheapies). The hood of my vehicle served as a rest. Shots at 20 yards or so, were centered, but were about 10" higher than POA. I switched over to the buckshot and the result was similar, with only a few pellets hitting the top of the target. I had taken the gun with me just to make sure it functioned,not to sight it in, but I was a little suprised with the result. Any ideas why it's hitting so high?

BTW: I'm not THAT bad of a shot.
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Last edited by ATTICUS; October 24, 2001 at 06:15 PM.
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Old October 24, 2001, 06:45 PM   #2
K80Geoff
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Have you ever checked the gun with birdshot on a pattern board? The gun may naturally shoot high because of the stock dimensions and your sight picture. You may need to adjust the stock to change Point of Impact.

With a bead sight your eye acts as the rear sight, and the position of your eye when you mount the gun to yur cheek determines where the shot will go. If you are shooting high the stock is too high for you.

You may need to reduce the comb of the gun or get a new stock.


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Old October 24, 2001, 07:37 PM   #3
Dfariswheel
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All 870's shoot high for me too. it's a matter of stock demenshions
and physical build. That's why I always have rifle sights on them.
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Old October 24, 2001, 07:38 PM   #4
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Thanks Geoff. Saturday was my first time out with this SG. I'll take a real target and a variety of shells out next time and find out exactly what it's doing. How do you adjust the stock to change point of impact? Are we talking carpentry, an add on cheekpad or what? Thanks
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Old October 24, 2001, 07:39 PM   #5
JNewell
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Which barrel?

The newer riot gun barrels have the bead on a little ramp, rather than sitting on the tube. This was done to lower the POI/POA issue that you're describing with slugs. If you're experiencing this with one of these later barrels, something's fishy.

On the other hand, maybe it's how you're mounting the SG? Are the slugs and buck hitting basically the same point of impact?
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Old October 24, 2001, 08:32 PM   #6
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This is an old police trade in (bead on the tube).

(Let me qualify the following- I was bow hunting Saturday and just took a few guns along to function fire)

The 00 buck was hitting close to the same spot, but it was hard to tell, I was using a file folder and a log as a target. At twenty yards, only three pellets per round hit the folder, and they were close to the same spot the slugs hit.

I also have a rifled slug barrel, with rifle sights (and a 2X scope), that I haven't tried yet.
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Old October 24, 2001, 11:14 PM   #7
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Hmmm.

You were using a rest. Did you try it without a rest? Your mount/cheek-weld provides your rear-sight on a bead-only weapon, and using a rest might be an unnatural position for you. Try it off-hand and see if that doesn't bring things back to COM.

Or, just aim lower.

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Old October 25, 2001, 12:51 AM   #8
8200 rpm
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My guess is that it's your sight picture; try changing it.

Bench type shooting forces your cheek to go way forward on the butt stock (where it's higher than the heel). This places your eye far above the receiver of the gun and misaligns the front bead.

Try putting your cheeck a little further back; like you would do if you were shooting at flying targets from the field. Then make sure you don't see any of the barrel. If you can see any part of the barrel, you will hit high. Make sure the bead and only the bead (not the bead platform or the end of the barrel) sits on top of the receiver.

If that doesn't work, getting a custom made butt stock to increase drop will just make the front bead dissapear. You might just have to get a new barrel.
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Old October 25, 2001, 06:41 AM   #9
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Try a few shots offhand and see what happens. If you're larger than average, add a spacer or two and see if the longer LOP drops POI.

Bead only 870s have always shot high for me with slugs.Hold low or add a ramp and bead.
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Old October 25, 2001, 07:37 AM   #10
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My first two shots were off hand. When I saw the POI (holy crap-was I suprised!) I used the hood as a rest. Thanks for the suggestions - my project continues.
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Old October 25, 2001, 11:20 AM   #11
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Atticus.. You may be able to shim the stock to get the correct point of impact. This takes a little knowledge of the gun and of course the proper wrench to remove the stock. Thin plastic shims strategically placed between the stock and receiver can change the dimensions of the gun.

This technique is usually used to move the stock right or left but can be used to move the POI up or down.

You should automatically gain the correct sight picture every time you bring the gun to your shoulder, if not the stock needs adjustment.

Beretta includes a set of shims with some of it's guns so shooter can make corrections. Maybee one day Remington will get its collective heads out of it's butts and do the same.


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Old October 25, 2001, 04:14 PM   #12
Rob62
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ATTICUS,

Adding the ramp under the bead will be the most practical and cost effective solution in my opinion. I've been fighting the very same problem that you have, and finally decided to get a set of ghost ring sights on mine.

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Old October 25, 2001, 09:32 PM   #13
K80Geoff
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Damn, now that's something I did not even think of. Raise the front bead to lower POI. It might work!


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Old October 25, 2001, 10:21 PM   #14
labgrade
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Atticus,

What (mumble) said about adjusting/shimming stock to receiver works. Went through similar experience recently with a 20 ga 870 Youth - just short for me.

Shimmed the upper portion of the receiver (.045" I think) where it makes contact with the receiver which effectively pushed the whole barrel aspect downwards.

This may work fine if it's a fit problem, but wouldn't if it is bead sight relative to receiver groove.

Far as shims go, I did have some very hi-tech, super-nifty platic shims left over from engineering days. I'd try backs of match books if that's all I had. See if it works & go nifty later.
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Old October 26, 2001, 05:31 AM   #15
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The best adjustable shim I've found is folded aluminum foil scissored into shape. Other folks use old business cards,toothpicks, shell boxes, and pieces of hulls.
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Old October 26, 2001, 10:06 AM   #16
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