1. Attention: We have put together a thread with tips and a tutorial video to help with using the new software. Please take a moment to check out the thread here: Trapshooters.com Tutorial & Help Video.
    Dismiss Notice

I have no explanation for this????

Discussion in 'Shooting Related Threads' started by senior smoke, Apr 9, 2013.

Thread Status:
Not open for further replies.
  1. senior smoke

    senior smoke Well-Known Member

    Joined:
    Sep 30, 2007
    Messages:
    7,557
    Location:
    Wauwatosa Wisconsin
    Hello:
    I recently purchased a Remington 870 28" choke tube field barrel from a neighbor. The barrel is like new and it came with three chokes Full, Mod, and cyl.

    I have never owned a choke tube barrel of any kind before but the price was right so I decided I have some time on my hands and I would try it.

    I placed a white middle bead on the gun along with a standard Bradley front bead. I patterned the barrel from a rest with the full choke tube inserted at 13 yards.

    A friend of mine has a gauge and the full choke tube measured .041. The barrel patterned straight but 50% of the pattern was below the line and 50% above. I made an adjustable stock and added bushings of 1/32 thickness to the comb but the poi hardly rose up with each added bushing???

    I had to place a total of six 1/32 washers in the stock before I noticed a poi diffrence where the pattern is now showing that it is now all above the line by only 2 inches????

    With every washer that I added the poi should have gone up above the line but did not. I have no idea why not, but it finally took a total of 6 washers before it clearly moved above the line that I was shooting at.

    Any one have any idea why the poi did not raise up with every bushing that was added as the poi finally raised up only 2 inches above the line after a total of six 1/32 washers were added?

    I am extremely puzzeled as I have never seen anything like this before.
    Steve Balistreri
     
  2. Oregunner

    Oregunner Well-Known Member

    Joined:
    Aug 15, 2006
    Messages:
    3,327
    Location:
    Oregon
    If you are still trying to stack the beads, you can override the comb being raised by getting into the gun harder. You should be able to start seeing a gap between the beads if you are mounting the gun the same way, and raising the comb. Keep adding washers, the pattern will come up. Mark
     
  3. hmb

    hmb Well-Known Member

    Joined:
    Jan 29, 1998
    Messages:
    9,406
    The barrel is possessed by demons. It took that many washers to overcome the force of the demons. HMB
     
  4. RobertT

    RobertT Well-Known Member

    Joined:
    Jun 27, 2006
    Messages:
    1,353
    Loose trigger nut.
     
  5. Stl Flyn

    Stl Flyn Well-Known Member

    Joined:
    Apr 6, 2010
    Messages:
    8,691
    Does the barrel wobble up and down when you shoot it, like it is made out of rubber?
     
  6. Bruce Specht

    Bruce Specht Well-Known Member

    Joined:
    Jan 29, 1998
    Messages:
    5,049
    Location:
    Near but not in chicago
    Barrel warp could be the issue here, The more times you fire the weapon the hotter the barrel get hence barrel warp altering the POI.
     
  7. 870

    870 Well-Known Member

    Joined:
    Jan 29, 1998
    Messages:
    2,390
    Seriously, how much were you expecting? Sounds like it moved a little over 2 inches, what else would be expected at 13 yds.
     
  8. slayer

    slayer Well-Known Member

    Joined:
    Nov 16, 2006
    Messages:
    2,928
    Location:
    beautiful northern michigan
    Oregunner nailed it. You are trying to keep the same sight picture so you are bearing down harder to stack the beads. Just hold your cheek lightly on the comb and you will see a wider and wider gap between the beads as you raise the comb. Bill
     
  9. wireguy

    wireguy TS Member

    Joined:
    Jan 29, 1998
    Messages:
    3,715
    "With every washer that I added the poi should have gone up above the line but did not."

    Steve, why do you believe this is true? Every gun and shooter combination is a law unto itself. While mathematically your assertion may be true,
    (or not) mathematics doesn't account for the human element.
     
  10. grntitan

    grntitan Well-Known Member

    Joined:
    Mar 25, 2009
    Messages:
    17,155
    Location:
    IL(The gun friendly Southern Part)
    Why were you patterning the gun at 13yds? Do you shoot 13yd targets? That distance is for checking POI.
     
  11. Unknown1

    Unknown1 Well-Known Member

    Joined:
    Nov 5, 2009
    Messages:
    3,396
    <blockquote><I>"Why were you patterning the gun at 13yds?"</I></blockquote>Good question!

    A 1/16" increase in comb height will raise the POI about 2" at 40 yards. You'll NEVER see the difference that 1/32" makes at 13 yards. Considering the variables in the mix, a 3/16" increase (6, 1/32" spacers) should raise your POI about 6 inches at 40 yards.

    Keller
     
  12. senior smoke

    senior smoke Well-Known Member

    Joined:
    Sep 30, 2007
    Messages:
    7,557
    Location:
    Wauwatosa Wisconsin
    You guys make some sense. I will try the barrel at 40 yards and see what happens. It actually took six spacers before I could not stack a figure 8 when mounting the gun. Subconsiously, I must of been bearing down hard on that stock to obtain my figure 8 without actually realizing it.

    Now watch, once I pattern at 40 yards my poi will most likely be a pattern and a half high? I will try and go out to the club to pattern sometime this week at 40 yards.

    As you can tell brains is not my strong suit. What ever, maybe I was blessed with good looks?
    Steve
     
  13. waverider

    waverider Well-Known Member

    Joined:
    Jan 29, 1998
    Messages:
    1,622
    Location:
    HI
    Actually you should be adjusting the comb for Point of Impact (POI) at 13 yards. From a rest you are seeing were the gun shoots. Also try some shots free hand to see where you are shooting at 13 yards.

    I think that you jumped the gun by putting a mid-bead on.

    You should adjust the comb to get the POI that you want. Once that is established then you put a mid-bead to get the fig 8. This way when you see fig 8 you know you have the gun mounted correctly and don't have to guess if the amount of space between the beads is correct.

    That said, after the above, you are at the point where you shoot at 40 yards free hand to confirm where the pattern is were you would be breaking the target. You can also see what your pattern looks like.

    Step 3 lock the trap for straight aways and see if the gun still shoots where it is suppose to for you.

    Jason
     
  14. senior smoke

    senior smoke Well-Known Member

    Joined:
    Sep 30, 2007
    Messages:
    7,557
    Location:
    Wauwatosa Wisconsin
    Jason, good advice.
    Thanks,
    Steve
     
  15. wlc

    wlc Member

    Joined:
    Jan 29, 1998
    Messages:
    534
    If your eye is 36" from the front bead and you cheek the stock the same after each adjustment, a 1/32" rise in the comb should result in the pattern moving up about .4" at 13 yards or 1.28" at 40 yards.
     
  16. slayer

    slayer Well-Known Member

    Joined:
    Nov 16, 2006
    Messages:
    2,928
    Location:
    beautiful northern michigan
    Jason.. great idea getting your sight picture and poi established before adding the bead. then you could place it so there is no gap. Have you done this? Bill
     
  17. senior smoke

    senior smoke Well-Known Member

    Joined:
    Sep 30, 2007
    Messages:
    7,557
    Location:
    Wauwatosa Wisconsin
    Dick:
    Here in the Milwaukee area we have had rain storms the last couple days going through the weekend. Rougly 4" of rain causing some flooding. The Gun club will most likely be under water.

    As soon as I can get out to the club I plan to pattern the barrel at 40 yards. My guns usually shoot 8" above line at 40 yards so I will have to see how many bushings I need. This appears to be one flat shooting barrel, or maybe it's this particular choke tube?

    Dumbest question I can think of. Do they make choke tubes that will shoot high if you need them too?
    Steve
     
  18. Oregunner

    Oregunner Well-Known Member

    Joined:
    Aug 15, 2006
    Messages:
    3,327
    Location:
    Oregon
    They do make chokes that change the POI, but really not worth the effort or the cost on an 870 barrel. There are thousands of old Wingmaster 30" fixed full choke barrels out there, that throw a great pattern. They were the standard on duck guns before steel shot. Mark
     
  19. senior smoke

    senior smoke Well-Known Member

    Joined:
    Sep 30, 2007
    Messages:
    7,557
    Location:
    Wauwatosa Wisconsin
    I put on my hip boots and went out to the local club to pattern my gun at 40 yards. Keller was right, my new barrel patterned 6" above the line at 40 yards.

    Years ago, I was told if you really want to know the true impact of a barrel shoot a slug through it. I still don't understand why the poi is not the same at 13 yards as it is from 40 yards. Someone please enlighten me.
    Steve
     
  20. zzt

    zzt Well-Known Member

    Joined:
    Jan 29, 1998
    Messages:
    3,457
    Location:
    SE PA
    Steve, 40 yards is 3x farther than 13 yards. So you can figure that whatever you get at 13 yards will be 3 times greater at 40. You were 2" high @ 13 so multiply that by 3 and you get 6" @ 40. That's what you just measured. This rule of thumb is close enough for government work.
     
Thread Status:
Not open for further replies.