VERY strange BSA problem.
- Thread starter Why not?
- Start date
- Location
- Southern Vancouver Island
Yes, like perhaps that barrel had a bore snake through 'er a few too many times or was cleaned from the muzzle with a cheap rod. Numerous factors in this case, but I reckon the tube be at least in need of a good re-crown to check results.
- Location
- Saskatchewan
convert it to a fence post? ;-)
A hunter bought a Ruger M77 to caribou camp and sprayed like your rifle. WE determined that there was a bulge in the barrel about 2" from the crown. Not noticeable on the outside but was visible from inside. I'm sure you checked this. That is a very large group. I don't think that a small change in powder will make it a shooter. Perhaps a flat based bullet would help bu it seems like a mechanical issue of some type
Neil
Neil
That has been my experience as well. To shoot 20 minutes of angle at 25 yards, the muzzle would have to be moving way more than an eighth of an inch.
Going to lop an inch off, crown, and see what happens when I get back home. It can't shoot any poorer.
Ted
Going to lop an inch off, crown, and see what happens when I get back home. It can't shoot any poorer.
Ted
You know that old saying about hindsight being 20/20, right?
Slugged the bore at the muzzle this evening,..... three times! It measures .282 inch. Should be no larger than .277
Surely, no one could clean vigorously enough from the bore to wear five thousandths of an inch out of the muzzle.
Going to push a lead ball all the way through from the muzzle, and see what it measures when it drops out of the chamber.
Ted
Slugged the bore at the muzzle this evening,..... three times! It measures .282 inch. Should be no larger than .277
Surely, no one could clean vigorously enough from the bore to wear five thousandths of an inch out of the muzzle.Going to push a lead ball all the way through from the muzzle, and see what it measures when it drops out of the chamber.
Ted
Johnn Peterson
CGN Ultra frequent flyer
- Location
- Chemainus B.C.
You know that old saying about hindsight being 20/20, right?
Slugged the bore at the muzzle this evening,..... three times! It measures .282 inch. Should be no larger than .277
Going to push a lead ball all the way through from the muzzle, and see what it measures when it drops out of the chamber.
Ted
Getting interesting, and 0.005" is a lot of wear/erosion! Good luck and keep us posted .
- Location
- Southern Vancouver Island
Ye'll figure 'er out Ted. We be pullin' fer ye. Of course there is always the 9.3 re-barrel option.
Of course there is always the 9.3 re-barrel option. 
Slugged the bore at the muzzle this evening,..... three times! It measures .282 inch. Should be no larger than .277
So where's my kewpie doll??? lol.
You know that old saying about hindsight being 20/20, right?
Slugged the bore at the muzzle this evening,..... three times! It measures .282 inch. Should be no larger than .277
Going to push a lead ball all the way through from the muzzle, and see what it measures when it drops out of the chamber.
Ted
You know, Ted, there is a distant possibility that someone fired that rifle with a minor "plug" right at the muzzle. This could bulge the muzzle slightly, without evidence of wear
or damage, other than the oversize bore. I had a M17 30-06 with about 1½" length of oversize at the muzzle, and it looked perfect, but shot very badly until we cut the barrel
back and recrowned. Dave.
Johnn Peterson
CGN Ultra frequent flyer
- Location
- Chemainus B.C.
So where's my kewpie doll??? lol.
And,
one for me as well? I suggested a similar tact in post #4.
Ted:
Why not (pun intended!) seat a 7mm bullet in one of your cases to see if it will chamber. Better yet, if a 7mm bullet falls into one of your fired cases, you know the chamber is large enough to accept 7mm bullets. If not, find a 7mm throater; in either event, now you've got a .280 / 7mm Express. 0.002" will NOT increase pressures dangerously, as long as you work your loads up, as you know.
I was going to post my disagreement earlier when everyone said it's got too large a bore, but I figured Nah, Ted's bullets would keyhole if it was, but silly me, I forgot to remember that a 7mm bore size has a 0.275" land diameter, yielding a 0.001" grip (each side) on the bullets. Probably not enough to result in any accuracy, but enough not to keyhole.
As for accuracy, or lack thereof, with both scope & iron sights (given the large bore, you can scratch my guess about one of the front scope base screws being too long so as to be touching the barrel threads), maybe make sure the front edge of the barrel swell beneath the rear sight is not binding at the front edge of its mating surface in the stock.
What about mounting the barrelled action to a piece of 2" or 3" square tubing secured via hose clamps, then secured to your shooting bench, fired single shot? That WILL eliminate bedding as a cause (a la benchrest rail guns).
Now, if we harken back to the 366 Warner debates, remember that you had a little light bulb go off after you had problems with mis-fires using Hornady brass? Why not (ha!, pun not intended this time) compare your fired brass to un-fired factory 270?
Really hope you wind up with a 282 Wagner, a MUCH better cartridge than O'Connor's pet.
Why not (pun intended!) seat a 7mm bullet in one of your cases to see if it will chamber. Better yet, if a 7mm bullet falls into one of your fired cases, you know the chamber is large enough to accept 7mm bullets. If not, find a 7mm throater; in either event, now you've got a .280 / 7mm Express. 0.002" will NOT increase pressures dangerously, as long as you work your loads up, as you know.
I was going to post my disagreement earlier when everyone said it's got too large a bore, but I figured Nah, Ted's bullets would keyhole if it was, but silly me, I forgot to remember that a 7mm bore size has a 0.275" land diameter, yielding a 0.001" grip (each side) on the bullets. Probably not enough to result in any accuracy, but enough not to keyhole.
As for accuracy, or lack thereof, with both scope & iron sights (given the large bore, you can scratch my guess about one of the front scope base screws being too long so as to be touching the barrel threads), maybe make sure the front edge of the barrel swell beneath the rear sight is not binding at the front edge of its mating surface in the stock.
What about mounting the barrelled action to a piece of 2" or 3" square tubing secured via hose clamps, then secured to your shooting bench, fired single shot? That WILL eliminate bedding as a cause (a la benchrest rail guns).
Now, if we harken back to the 366 Warner debates, remember that you had a little light bulb go off after you had problems with mis-fires using Hornady brass? Why not (ha!, pun not intended this time) compare your fired brass to un-fired factory 270?
Really hope you wind up with a 282 Wagner, a MUCH better cartridge than O'Connor's pet.
Back home, and pushed a slug all the way through from the muzzle to the chamber.
Here's the answer, Gentleman.
Unfortunately, cutting and turning a new crown on this barrel isn't going to change anything when the smallest diameter of the grooves are a tad over 0.282 inch diameter.
The barrel is bright with sharp rifling, and has all the proof marks and 270 W calibre roll stamp. Evidently it is a 7mm barrel that was inadvertently chambered in 270 Winchester.
Somehow, a 7mm barrel ended up in the 270 rack, and made it all the way through the process. I can understand this happening because BSA chambered rifles in 7X57. I have had two of them in the past.
Tried putting a 7mm/.284 bullet into a fired case, and it won't even begin to slide in, so it certainly isn't going to chamber a loaded round with one in it. The easy answer? A rechamber to 280 Remington.
Ted
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