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.

Fixed Choke Fixes

Discussion in 'Shooting Related Threads' started by v-strom 650, Aug 17, 2012.

Thread Status:
Not open for further replies.
  1. v-strom 650

    v-strom 650 Member

    Joined:
    Sep 13, 2010
    Messages:
    136
    Just aquired a very clean and lightly used older fixed modified (*-) BT99. Love how the gun shoots and feels but am wondering if there are any proven ways to tighten up or increase the density of the pattern for the occasional times I have to shoot from longer yardage. (non ATA shoots) Does a longer forcing cone really work for that as they claim? Certain combos of wads and powders? (I don't like high velocity shells) The barrel has not been messed with and I would rather not have tubes put in or stick a bunch of $ in it. (might as well buy another gun or barrel) Thanks for your help, J. Terre
     
  2. bonzai272

    bonzai272 Member

    Joined:
    Nov 11, 2009
    Messages:
    275
    Just an FYI, if your barrel is *- then it is improved mod. * is full and ** is mod.

    Page 28 of the link.

    http://media.browning.com/pdf/om/bt99_02260_om_s.pdf
     
  3. miketmx

    miketmx Active Member

    Joined:
    Jan 29, 1998
    Messages:
    2,609
    I had a 2 barrel set and the ** Modified measured .028 constriction and the * Full measured .038 constriction. Your Improved Modified may pattern just great but you will have to test it.
     
  4. v-strom 650

    v-strom 650 Member

    Joined:
    Sep 13, 2010
    Messages:
    136
    Thanks guys! On the pattern board it shot looser than the last IMOD I tested and I must have had a brain fart on the markings! (It does shoot a beautiful even pattern for sure!) So my question still remains; any proven tricks that improve densities? J.Terre
     
  5. Avaldes

    Avaldes Active Member

    Joined:
    Jan 29, 1998
    Messages:
    1,651
    Location:
    Central Coast of California
    Yes, send to Tom Wilkinson to have the chokes tightened. He is the barrelsmith to the stars. He can make your gun shoot whatever pattern you like.
     
  6. bonzai272

    bonzai272 Member

    Joined:
    Nov 11, 2009
    Messages:
    275
    Forgot to mention, I too recently picked up an older BT99 with *- IMOD fixed choke like yours. Ive been using it for the past month in my summer league and it still hits pretty well all the way back to the 26-27 yd line.

    Avaldes, I had no idea you could tighten the choke. Ive heard of opening them by removing metal but havent heard of the other way around. Im guessing they just add metal to tighten it?
     
  7. deankol

    deankol Member

    Joined:
    May 5, 2011
    Messages:
    137
    Backboring the barrel and leaving the choke ID the same will tighten the constriction.
    It's choke ID relative to the bore.
     
  8. Ajax

    Ajax Active Member

    Joined:
    Jan 29, 1998
    Messages:
    1,866
    If the barrel has enough metal a good smith can back bore it, and that in effect tightens up the choke. It does change the weight of the barrel and some people do not like that.

    Ajax
     
  9. Johnny

    Johnny Active Member

    Joined:
    Jan 29, 1998
    Messages:
    2,151
    Try some AA Handicap loads for those " occasional times" before you mess with the barrel.
     
  10. hmb

    hmb Well-Known Member

    Joined:
    Jan 29, 1998
    Messages:
    8,160
    Use 7 1/2s for long range and 8s for close up targets. HMB
     
  11. Avaldes

    Avaldes Active Member

    Joined:
    Jan 29, 1998
    Messages:
    1,651
    Location:
    Central Coast of California
    Having Wilkinson rework your barrel will cost around $400. You may ask yourself if that is worth it or if that money wouldn't be better spent on another gun/barrel. From what I know, he doesn't just backbore, but he profiles the barrel to get just the right pattern. It is s level of machining accuracy that a mass produced gun can't get due to costs.
     
  12. v-strom 650

    v-strom 650 Member

    Joined:
    Sep 13, 2010
    Messages:
    136
    Bonzai, what loads worked for you? Johnny, I thought I read or was told that slower loads pattern tighter; so won't handicap load patterns be looser? (plus I would hate the recoil! lol) Doesn't increasing velocity increase deformation of the shot and cause more flyers? Are the claims of some wad and powder makers of "tighter patterns" w/ their product false? I don't think I would spend $400 on barrel work on a $900 gun unless I was a lot more invested in the gun time and confidence wise. (Though I think what Wilkenson does may have some validity) However $50 for a forcing cone lengthening might be worth it IF it results in 5-7% increases in pattern density as claimed. Just wondering if anyone on this board had done some actual testing to see if these products and services do work. Trying new powders and/or wads would not be too tough or expensive to do. The fun would be in the experimenting I guess, JTerre
     
  13. bonzai272

    bonzai272 Member

    Joined:
    Nov 11, 2009
    Messages:
    275
    Ive been using the Federal Gold Medal Target loads in 7.5 shot. Ive shot both the 3 dram and Handicap dram loads. If you want to have your barrel backbored and polished as some mentioned above, Mike Orlen will do it for $165. And he only charges $55 to lengthen and polish the forcing cone.
     
  14. Johnny

    Johnny Active Member

    Joined:
    Jan 29, 1998
    Messages:
    2,151
    v-strom 650 , You said "longer yardage. (non ATA shoots)" so I assumed you meant long yardage games. So, you won't do any better than AA Handicap loads. I don't think you really know what you have or how it shoots. I would bet it shoots just fine and you may not gain a thing by have the barrel "profiled." Don't waste your money on longer forcing cones. You won't gain anything, certainly not 5-7%, and you might lose.

    You ask about actual testing, yes, Neil Winston has tested all of this stuff. Except for actually changing the choke constriction, none of the gimmicks actually make any real difference. You may not gain much there. He did a test of IM against Xf and there was no real difference there either. As for less velocity and tighter patterns, Neil has tested that also. Not much there either. For tighter patterns load hard shot. Sorry but there is no magic. Do a search for Neil Winston and you will find all this info.
     
  15. HTSmith

    HTSmith Member

    Joined:
    Feb 13, 2010
    Messages:
    320
    Location:
    Central North Carolina
    I load green dot at 1145 fps when I want tight patterns. Its a lot cheaper than barrel work.
     
  16. v-strom 650

    v-strom 650 Member

    Joined:
    Sep 13, 2010
    Messages:
    136
    Thanks to all for the responses and info. Johnny: thank you for the search tips, I had forgotten how much Neil had done. Sorry I wasn't clear about the yardages I wanted, (no further than 25 for winter jackpot shoots) and you are right on that I don't know what I have yet. The gun is new to me; I just picked it up at the Grand and so far have only POI tested it and shot a few patterns w/ my regular 1 oz loads of 8 shot @ 1200fps. I'll be spending some time w/ it this weekend. One time TTT to see if anyone else wants to add to the discussion. J.Terre
     
Thread Status:
Not open for further replies.