After re-barrel :: 2 shots close together and 1 shot further out

[Brad7348]

Oh forgot to ask, have you seen any oval shaped holes in your target, or all they consistent and perfectly round.

 

[Carlos88]

I appreciate all the suggestions from everyone. This thread will be a good reference for others. But I'm asking one simple question - has anyone experienced a barrel the was responcible for a 2-plus-1 pattern. Maybe the answer is "no".

Yes and it was related to the front base, front scope mount screw. Take the base off and look down into the screw hole. If you see a compressed thread or "shiny" mashed thread you need to shorten the screw approximately .010, remount base and scope and go shoot your rifle again.

Actions that are "blueprinted" and rebarelled are particularly susceptible to this problem. Through the years I've seen this problem several times.

 

[robpiat]

I appreciate all the suggestions from everyone. This thread will be a good reference for others. But I'm asking one simple question - has anyone experienced a barrel the was responcible for a 2-plus-1 pattern. Maybe the answer is "no".

I have, but it was a mag issue that showed up as L-R-L-R-L etc. Only when you get past 3 can you start troubleshooting.

 

[MNbogboy]

I appreciate all the suggestions from everyone. This thread will be a good reference for others. But I'm asking one simple question - has anyone experienced a barrel the was responcible for a 2-plus-1 pattern. Maybe the answer is "no".

My answer is yes, several times. Most often bedding. Seating will also almost always help close a 1moa or less group.
Powder and powder nodes can be the difference in night & day, from scatter nodes to tolerant precision.
There have been a lot of great suggestions here.
I think that if your stock torque is causing binding of the bolt then bedding is where i would start. Torque tuning can be useful in well fitting or properly bedded stocks. It has been said the harmonics of the action are important and i believe that.
Before doing anything i would use "full" action torque and do a slow methodical 10 shot group. Also if possible check velocities with a non-attached chrono. If you only have access to a Mag-speed do a second 10 shot test.
There is most often no one answer but my bet is on bedding.
Good luck

 

[mongo4567]

I answered the 2 + 1 question indirectly. I have seen this. For me, I see the one by itself as a flyer. I get more clarity with a 5 shot group. Sometimes it was a powder, bullet change. I have seen due to barrel heating: barrel relief/wandering zero.

 

[Brad7348]

Yes and it was related to the front base, front scope mount screw. Take the base off and look down into the screw hole. If you see a compressed thread or "shiny" mashed thread you need to shorten the screw approximately .010, remount base and scope and go shoot your rifle again.

Actions that are "blueprinted" and rebarelled are particularly susceptible to this problem. Through the years I've seen this problem several times.

good point! This happened to my brother. His rail came with screws that were a hair too long and even through they were tight, they had bottomed out and the rail was not snug, I could wiggle the rail with my hand with a fair amount of pressure. Turns out the screw was bottoming out on the barrel threads inside the action rather than snugging the the head of the screw on the the rail. This shouldn't happen on the rear since the scope mount holes are generally threaded all the way through the action into the bolt raceway, but in the front the barrel tenon is there in the way below the hole/s.

 

[Rich Coyle]

I think it's the size group your rifle will fire if you fire more shots into the group.

 

[Carlos88]

good point! This happened to my brother. His rail came with screws that were a hair too long and even through they were tight, they had bottomed out and the rail was not snug, I could wiggle the rail with my hand with a fair amount of pressure. Turns out the screw was bottoming out on the barrel threads inside the action rather than snugging the the head of the screw on the the rail. This shouldn't happen on the rear since the scope mount holes are generally threaded all the way through the action into the bolt raceway, but in the front the barrel tenon is there in the way below the hole/s.

There you go. It can certainly be a factor.

 

[436]

Is it possible for a new barrel to be the cause of 2 shots being VERY close together and a third shot being 1/2" to 3/4" apart? The shot that is "out" can be the 1st, 2nd, or 3rd shot.

This is on a Tikka T3 Varmint in 22-250 Rem. Using the original, factory stock. It use to shoot amazingly well.
Replaced the barrel with a Rem Varmint contour, 1:12 twist. Had to reduce the breach end to 1.150" to better match Tikka action.
I was hoping to use close to the same load that worked well in the original barrel so I had the gunsmith cut the finished length to match original barrel.

Things I've tried:
1. Different charge weights (OCW type of test)
2. Different seating depth of bullet
3. Open up barrel channel a little more.
4. Inspect bedding area and then overall stock for any crack.
5. Use a different, known good, scope
6. Use a different scope mount, (to remove the rail). Used the Tikka Optiloc rings and another different scope.
7. Try a different bullet

Have any of you seen a new barrel be the cause of such behavior?

Thanks -- Todd

It's a long shot, check the parallax on your scope(s) The other might be canting your rifle are you using a bubble? and is your scope vertically aligned? Just taking a stab at it.

 

[Remhunter]

I've experienced that exact same thing many times. Typically it is with thin pencil barreled rifles. Had a Remington 700 Mountain Rifle chambered in .280 and after 2 shots the third would always be a flyer due to the barrel heating so much. Could not shoot 3 rounds groups with that gun, but that gun was not intended for that. In other rifles it was caused by loads the gun didn't like or improper torque on receiver screws. I would check torque on the receiver screws, make sure the barrel is free floating, and then if those don't work change the load. I have talked to many people that rebarrel and go to their pet loads and they don't shoot them. Changing the barrel absolutely changes the gun.

 

[greenejc]

Is it possible for a new barrel to be the cause of 2 shots being VERY close together and a third shot being 1/2" to 3/4" apart? The shot that is "out" can be the 1st, 2nd, or 3rd shot.

This is on a Tikka T3 Varmint in 22-250 Rem. Using the original, factory stock. It use to shoot amazingly well.
Replaced the barrel with a Rem Varmint contour, 1:12 twist. Had to reduce the breach end to 1.150" to better match Tikka action.
I was hoping to use close to the same load that worked well in the original barrel so I had the gunsmith cut the finished length to match original barrel.

Things I've tried:
1. Different charge weights (OCW type of test)
2. Different seating depth of bullet
3. Open up barrel channel a little more.
4. Inspect bedding area and then overall stock for any crack.
5. Use a different, known good, scope
6. Use a different scope mount, (to remove the rail). Used the Tikka Optiloc rings and another different scope.
7. Try a different bullet

Have any of you seen a new barrel be the cause of such behavior?

Thanks -- Todd

Right, left, up, down? Looks like your barrel is walking as it heats. Get it Cryogenically treated and that might solve the problem.

 

[Mike Matteson]

I shoot a 220 Swift and for years. Try IMR4064 powder. I used it in several swifts with very good groups with most touching at 100yrs, and under 3/8". All our barrels are heavy or bull barrels. Those barrels are 1-14 twist, and between 24 1/2" to 26" barrel lengths. We use 52,53, & 55gr Sierra bullets. The other is you need to check each shot to see which one is flying. When the 22-250 came out they were using a 1-14 twist. I see you are using a 1-12 twist barrel. That maybe a little quick for a 55gr bullet. Some barrels like being fouled, and others being clean. I would also try a heaver bullets being you are using a faster twist. Why did you shorten the barrel to start with? Leaving the barrel longer does this. As the throat burns out, and the muzzle wares out. The barrel can be cut down to put it back into working order. You are not braking in a new barrel.

 

[Ronbla3]

Had the same problem. Changed from cci to fed primers. Same everything else problem solved. Try it, it might work. ONLY change one thing at a time.

 

[emp1953]

I've experienced that exact same thing many times. Typically it is with thin pencil barreled rifles. Had a Remington 700 Mountain Rifle chambered in .280 and after 2 shots the third would always be a flyer due to the barrel heating so much. Could not shoot 3 rounds groups with that gun, but that gun was not intended for that. In other rifles it was caused by loads the gun didn't like or improper torque on receiver screws. I would check torque on the receiver screws, make sure the barrel is free floating, and then if those don't work change the load. I have talked to many people that rebarrel and go to their pet loads and they don't shoot them. Changing the barrel absolutely changes the gun.

The barrel IS the gun.