What is my next step?

Mike Bryant said:
Ben, have you checked your bedding job with a dial indicator between the barrel and forend? A bedding job can look good, but a dial indicator will tell whether the action is laying in the bedding stress free. I consider anything under .002" movement between barrel and forend good. If there's more movement than that then I rebed. Usually, all you have to do is loosen off the front receiver screw and the dial indicator will show whether the bedding is good or not. Holding the rifle vertically or upside down horizontally will work to test the bedding. On a small contour barrel, two flat pieces of steel bolted together clamping onto the barrel will help hold a magnetic indicator base in place and steady. It helps to drill out the guard screw holes to 5/16" to make sure that the guard screws aren't touching inside the pillars or stock if there aren't any pillars. A rifle that won't shoot can cause you to doubt a lot of things. Hopefully, they are few and far between.
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Mike, your very thorough, and I like the quantified approach. I'll try that.

My go by feel method leaves a lot of doubt indeed.

It's funny, when I'm embarrassed to type it, I can only admit to myself it must be sloppy.

To rebed, if necessary, can I just sand up the surface off the old bed and skim bed, or should I take the time to try to remove all the old stuff?

Ben
 
There are more things to check when building a rifle than there are
operations in building it. As we assemble each item, we have interactions
that need to be accounted for, adding to the check list. Invariably the
things we assume are ok, may not be. Check everything as you complete
each operation and you will have few surprises.
 
I have ~100 riles, and I help other at the range.

A) Fully 1/2 of all my problems and other's problems with bad groups are caused by scope mount screws being loose.

No one likes to take the rings and scope off, because the zero is lost.

I have never had the problem when I clean the oil off the screw and out of the hole and use Loctite 242 on the threads. I also glass bed between the mount and the receiver to get the scope tube parallel to the barrel and bind free.

B) New premium barrels sometime foul quickly. That makes me, a guy who does not believe in breaking in barrels, act just like I am breaking in the barrel. Shoot a group and clean Copper, shoot a group and clean Copper...
 
Check firing pin

Check that firing pin is staying "trapped" in the firing pin hole at front of bolt or that "boss" on pin is large enough to keep pin aligned if pin leaves hole in front of bolt.

If it does not stay aligned--it will make wide flyers
 
Jim Borden said:
Check that firing pin is staying "trapped" in the firing pin hole at front of bolt or that "boss" on pin is large enough to keep pin aligned if pin leaves hole in front of bolt.

If it does not stay aligned--it will make wide flyers
Click to expand...

Jim,

I'm not sure how to check this, but there are two things to mention.

The firing pin is striking quite well centered (by eye) in the middle of the primer.

I did have 1 misfire in my first few shots, where the pin did not detonate the primer. I stripped the bolt and found lots of sticky oil residue, and I cleaned appropriately with no problems later.

Ben
 
Bnhpr said:
My new rifle shoots a 1" to 2" group at 100 yards. Best it will do. 2 may touch, then bang, its 2" out on the 3rd shot.
Click to expand...

Ben,

Is it always the third shot that is thrown out of the group? If so try letting the barrel cool for 5 minuets between each shot. Lighter contour barrels can sometimes change point of impact as they heat up.

Todd
 
ACArms said:
Ben,

Is it always the third shot that is thrown out of the group? If so try letting the barrel cool for 5 minuets between each shot. Lighter contour barrels can sometimes change point of impact as they heat up.

Todd
Click to expand...

I have a 10/22 with a Majestic Arms 17M2 barrel with Lothar Walther liner.
The barrel looks like a bull barrel but is very light.
It shoots two holes touching at 50 yards, and the third shot is 1" away.
It does this every time.
I would think that heating up would be gradual, but it makes a quantum leap between #2 and #3.
 
Clark,

This is an extreme example but, I had a customer bring me a Remington 700 that he said shot all over the place and asked if I could check it out. Now this rifle had been modified by one of the companies that do the carbon wrapped barrels. It was chambered in 300 WSM. I took it to the range, fired two shot to get on target and then let it cool 15 minutes before shooting the first group. The first group measured approximately 4”, all vertical, with each shot moving about 2” above the last. So I let the gun cool for 15 or 20 minutes and then shot the next three shot group firing each shot in five minute intervals, the group measured .620. Like I said this is an extreme example.

In the case of Ben’s or any rifle for that matter, if the bore of the barrel is not perfectly straight, and none of them are, somewhere in the length of the barrel one side is thinner than the other. As the barrel heats up, the thin side expands faster than the other and the point of impact will change, and since Ben’s barrel is a sporter contour it will heat up faster than say a target contour barrel. and the point of impact change will show up quicker, that is why I asked if it was always the third shot.

I am not saying this is the answer, just another that can be easily explored.

Todd
 
I don't remember anybody wondering about the crown, a little off or dinged would explain everything.

Ross
 
The crown was fine, but I re-cut it anyway already...no change.

My explanation was an example...sometimes the first 2 are 2 inches apart, and the first shot can be anywhere in a 2" circle.

The rifle doesn't shoot. Cold, hot or in between.
 
Mike Bryant said:
Ben, have you checked your bedding job with a dial indicator between the barrel and forend? A bedding job can look good, but a dial indicator will tell whether the action is laying in the bedding stress free. I consider anything under .002" movement between barrel and forend good. If there's more movement than that then I rebed. Usually, all you have to do is loosen off the front receiver screw and the dial indicator will show whether the bedding is good or not. Holding the rifle vertically or upside down horizontally (resting the barreled action in a gun cradle) will work to test the bedding. On a small contour barrel, two flat pieces of steel bolted together clamping onto the barrel will help hold a magnetic indicator base in place and steady. It helps to drill out the guard screw holes to 5/16" to make sure that the guard screws aren't touching inside the pillars or stock if there aren't any pillars. A rifle that won't shoot can cause you to doubt a lot of things. Hopefully, they are few and far between.
Click to expand...


Well, I got this rifle sorted.

It was the stock. Thinking about what Mike said above, I did notice the front action screw didn't "break" like it should. It too 2 revs before i could switch the allen wrench around and use the fast end. Dial indicator moves .030"...bed looked good but was distorting the action.

She's sitting in new bedding compound as I type this.

What sealed the deal was... when I took the action/bbl out of the laminate stock and put it in a B&C stock with a aluminum block. Stock is ugly as sin, but functional.

First round hit the X on a 100 yd score target. Second round, 1/4 to the right of it. Next 4 rounds went chewed the hole on the right of the X up to about the size of a 30 cal hole.

Started getting tons of mirage as the bbl warmed up (29 degrees out) so, they started hitting around the hole, but still in a 5/8" group.

More what I x-pect from this setup.

I'm now happy again. Bedding attemp #2!

Thanks for the help everyone.

Ben
 
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