What bullet jump to expect from a new barrel?
#1
Thread Starter
Fork Horn
Joined: Feb 2003
Posts: 494
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From: Altadena CA
I just had a 'smith rebarrel my 22-250 with a Lilja heavy barrel. Even after careful break-in, it shot terribly (2" at 100 yds). I got out the Stoney Point gauge, and it shows 0.15" of bullet jump. My understanding is that 0.02-0.04" is more the norm, but the 'smith said there's nothing he can do for me.
I've already checked the usual suspects (free floated barrel, scope screws, ammo, etc.), and I think the culprit is excessively long bullet jump. For this I paid $700???
I returned the rifle to him tonight. He said he'd "look at it," but I didn't leave his shop with much of a warm and fuzzy feeling.
Am I getting hosed?
I've already checked the usual suspects (free floated barrel, scope screws, ammo, etc.), and I think the culprit is excessively long bullet jump. For this I paid $700???
I returned the rifle to him tonight. He said he'd "look at it," but I didn't leave his shop with much of a warm and fuzzy feeling.
Am I getting hosed?
#4
Joined: Feb 2006
Posts: 493
Likes: 0
I think your talking about freebore, all I know is that a bullet which has to travel an excessive distance before engaging the rifling can become slightly upset and accuracy goes south. Also a bullet which is seated to contact the rifling will make chamber pressure rise sharply. Might you seat your bullets further out of the case and minimise the jump, if your magazine will allow it. Also isn't that deminsion machined into the barrel by the manufactuer.? If so would you go to the gunsmith for a solution or to the Mfgr. Just thinking a little over my head, Glenn.
#5
Nontypical Buck
Joined: Feb 2003
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From:
Since the rifle has a Lilja barrel, andthe rebarrel job ranyou $700.00 the rifle should shoot very well. Don't let the gunsmith get away with it.
The same thing happened to a friend of mine; the best his rifle would group is 2.5", but he did not pressure the gunsmith, and he is stuck with a unaccurate rifle. Good luck.
The same thing happened to a friend of mine; the best his rifle would group is 2.5", but he did not pressure the gunsmith, and he is stuck with a unaccurate rifle. Good luck.
#6
Joined: Mar 2006
Posts: 257
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Fifteen thousandths doesn't sound like a whole lot of free-bore. If I remember correctly, Weatherby rifles have much more than that, right from the factory. How does the crown on the muzzle look? A poorly machined or damaged crown can ruin accuracy in a hurry. The good news is that recrowning the barrel should be inexpensive and easy to do.
After you've exhausted all other possible solutions (ammo, bullet seating depth, scope, crown, etc.), and if your current gunsmith is unable/unwilling to help you, another gunsmith should be able to turn down the back of the barrel and recut the chamber. In effect, you can start over, without having to buy a new barrel or spend another $700.
Good luck.
After you've exhausted all other possible solutions (ammo, bullet seating depth, scope, crown, etc.), and if your current gunsmith is unable/unwilling to help you, another gunsmith should be able to turn down the back of the barrel and recut the chamber. In effect, you can start over, without having to buy a new barrel or spend another $700.
Good luck.
#7
Thread Starter
Fork Horn
Joined: Feb 2003
Posts: 494
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From: Altadena CA
Thanks for the replies so far, gentlemen.
Re.seating the bullet out further, the cartridge OAL is already a hair above max; any further lengthening and the cartridges wouldn't fit in the magazine.
I'm not talking about headspace or freebore, I'm talking about bullet jump, which is the word Stoney Point uses to describe the term. Headspace is not a problem, since the round seats firmly against the shoulder of the chamber.
I've tried two loads: My reloads that always shot well in the previous factory barrel, plus some factory Winchesters. Both shoot poorly.
If the crown is bad on a new barrel, then I assume it's the gunsmiths problem and something he should fix.
Keep the comments coming, guys!
Re.seating the bullet out further, the cartridge OAL is already a hair above max; any further lengthening and the cartridges wouldn't fit in the magazine.
I'm not talking about headspace or freebore, I'm talking about bullet jump, which is the word Stoney Point uses to describe the term. Headspace is not a problem, since the round seats firmly against the shoulder of the chamber.
I've tried two loads: My reloads that always shot well in the previous factory barrel, plus some factory Winchesters. Both shoot poorly.
If the crown is bad on a new barrel, then I assume it's the gunsmiths problem and something he should fix.
Keep the comments coming, guys!
#8
Fork Horn
Joined: Oct 2004
Posts: 321
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From:
one hundred fifty thousandhs (.150) is excessive if that is the distance from the riflling to the ogive of the bullet... therefore you have a deep throat in that barrel.... but you don't say what you are shooting from it, which bullet, if you are handloading and what your COL is....
when that barrel was chambered, a reamer was used to cut it... that reamer has a set throat length on it... which is pretty much "standard"... to change the throat length you'd have to custom grind a reamer (or find one with a shorter throat already) to shorten the throat...
so, in order to correct the length of bullet ogive to rifling you'll have no other option than to either A) seat the bullet out further or B) find a longer bullet.
even if you found a reamer with a shorter throat you'd have to remove the barrel, face off the end to shorten up the chamber (short chamber the barrel) and run the new reamer in to depth and then reset headspace....
btw, i am not of the school where just a barrel will transform a gun into a cloverleaf generator... has to be right from the recoil pad to the crown IMHO.... that includes the ammunition in the chamber... and that can be the most frustrating part as the combinations of bullets, powders, primers, cases and reloading methods for 22 caliber are endless...
JR
when that barrel was chambered, a reamer was used to cut it... that reamer has a set throat length on it... which is pretty much "standard"... to change the throat length you'd have to custom grind a reamer (or find one with a shorter throat already) to shorten the throat...
so, in order to correct the length of bullet ogive to rifling you'll have no other option than to either A) seat the bullet out further or B) find a longer bullet.
even if you found a reamer with a shorter throat you'd have to remove the barrel, face off the end to shorten up the chamber (short chamber the barrel) and run the new reamer in to depth and then reset headspace....
btw, i am not of the school where just a barrel will transform a gun into a cloverleaf generator... has to be right from the recoil pad to the crown IMHO.... that includes the ammunition in the chamber... and that can be the most frustrating part as the combinations of bullets, powders, primers, cases and reloading methods for 22 caliber are endless...
JR
#10
ORIGINAL: BTM
I'm not talking about headspace or freebore, I'm talking about bullet jump, which is the word Stoney Point uses to describe the term. .
I'm not talking about headspace or freebore, I'm talking about bullet jump, which is the word Stoney Point uses to describe the term. .


