You don't tell us much about the rifle. Is there a fly in the hammer? a bad fly will give you stringing.  if it is a Highwall that comes to full cock I would grind out the half cock notch and lose the fly. That has cured a stringing problem for me.

40 Rod

Dick,

  A seating depth of 1/16" is just a nominal depth to seat the bullet. I'd try seating it out further.

  From your description it sounds like the rifle has a very long throat/Leade in it. Freebore as some call it. Not being able to seat the bullet out might be causing a partial gas leak which would vary the MV enuf to cause vertical stringing.

  The fact that the bullet isn't engraving like a "normal" Schuetzen bullet should does not necessarily mean that's the problem. You really need to do a chamber cast so you can size your bullets to fit that throat. For shooting cast bullets in military guns it's pretty well standard practice to size the bullets to fit the throat. A good example would be my 03 Springfield. It has a .301 bore, a .3085 groove, and a Leade of .311. I size .311. Don't know if you've tried this angle but if not it's worth a try to.

  You don't mention the caliber, or bullet wgt. you're trying in it. You mention it having 1500 rds. thru it. So was the gun possibly used for another venue of shooting, like Shilouette, or Long Range? Some of those shooters deliberately have longer throats put in so that they can seat their bullets out further to increase powder capacity.

  If this is the case, and sizing to fit the Leade, or seating the bullet out further doesn't help your only course might be to have the barrel set back, or a new one put on.

PETE

Pete, Marty, thanks for the suggestions. Took the rifle back out yesterday and bumped the powder charge up to 16 grs. 4227, at the edge of safey (33-47, 248gr. bullet) but no real improvement. I've owned and operated 4 single shots in the past. In each case the bullet was seated just ahead of the case and the rifling engraved halfway into the base band. All of these rifles were competitive as to accuracy. I seated this bullet out to the extreme of the seater, .380 and it still strung the shots. The bullets mike "good" but I've sent sample to the maker. I am thinking that the barrel must be re-throated for starters. Let that bullet engrave deeply into the base band. What I'm not going to do considering the money involved to date is chase my tail, hopefully. As a sanity check took out a CPA in .32-40 this am, fired 14 shots with a mix of bullets to include 3 I borrowed 2 years ago from Chuck Blender, hand lubed 2 with a stick of what I think is 20 year old Dell 59, and all of the shots went in 2.45 !

Dick

Pete, .380 is right. This is the length the bullet must be seated ahead of the case to have the rifling engrave almost to the bullets base. The problem is that the seating position has created another cartridge!. As has been demonstrated, the smaller capacity case, i.e., .32 Miller Short, etc, are setting the standards for accuracy. But in this rifle a compressed load of Swiss 1.5 still exhibited a stringing problem.

Dick

Dick, you and I have talked about the "throating" problem in your rifle barrel.  I still think the answer is to make a chamber cast to include the throating to the rifling. Send that to a reputable mould maker and let them create a bullet that will fit.  Obviously, the present bullet is wrong and will never give you the accuracy you want.

As we talked about earlier, I have this same chambering with the same reamer in my rifle and the rifling barely engraves the base band on the bullet.  However, accuracy is much better than what you have gotten.  You have a Badger--I have a Ron Smith barrel.  I don't know if that has any bearing on the accuracy. I plan to do the chamber cast and have a bullet made that will fit to see if accuracy is any better.  I think it will be noticeable.

Pete, the cartridge is .33-47. 

coolhd

Jim, I just miked and examined under high magnification a bullet seated appx. 1/16 ahead of the case. The bullet is tapered and it engraves begining slightly ahead of the uppermost band where diameter is .335, as it should be. The engraving stops .315 above the bullet base. What we have here is a throat that is simply too long. Instead of chasing molds, chamber casts, etc., I'm just going to return the action and barrel and have it set back specifiing where I want the rifling to engrave to. Perhaps I could seat it out to the limit of the seater, try all sorts of powders, but we are really venturing into the unknown. Just consider how much more case capacity results from having a bullet .380 ahead of the case. Speaking of bullet diameters I found an old stubby Barnett bullet that after seating shows very tiny rim of lead around the base. As I recall it shot well. So I going back to basics. Now I'm a little concerned re: you noting that the .339 may not be large enough. Mine is the same and I note that it appears the bore not in contact between the engraving by the lands. Only testing will tell. 

Pete; the cartridge is called a 33-47.

Dick

Good suggestion. I even used upward thumb pressure to be sure the scope had repositioned after each shot. The accuracy was not radically bad, though for bench rest is was a disaster, stringing shots a  minimum of 3" at 200 yards. The maker emailed me that they are working on it, I feel they found the throating less than desirable. I will clean my scope and mounts.

Dick