116 barrel off centered in stock. Breechface/chamber aligned?

Alright guys, I have a 116 30-06 that is 100% factory. Actually it’s a replacement for a 116 I had bought that was replaced under warranty. Maybe I should have sent it back when it arrived but thought I would see what it would do.

The barrel is close to touching on one side of the stock. Still floated, just really close.

Decided to work up some reloads for it since I’ve only been shooting factory ammo. Firstly, I wanted to check the distance to the lands. I colored a bullet(165 gr Sierra GK) with a sharpie and set it 3.33 OAL. This is OAL from Sierra Load manual. At 3.33 I’m making contact. But I’m not liking what I see. About half of the bullet circumference I have nice imprints from the lands, the other half is just a line with no marks from lands. Walked the seating depth down to 3.2835. Still getting contact with something leaving a scuff mark. This is on the lower side of chamber. No marks from lands @ this measure.


I do not have a way to measure concentricty of my reloads although I doubt that is the cause. Always occurs on lower side of chamber.

Once fired Remington and Federal cartridges also exhibit a slight bulge on one side of the case just ahead of the case head.

Ill see about getting some pictures uploaded and some measurements from the micrometer.

I also do not have a borescope.

There are no pressure signs with factory ammo. Rifle shoots decently although it does walk a little as the barrel gets hot, but for a hunting rifle only one or maybe two shots are all that is ever needed.

Recommendations for checking things out?

Edit. Some numbers. Contact with edge occurs (No lands marks) down to 3.2835 and maybe lower, but that’s as far as I got adjusting seating depth. Marks appear at bottom edge of bullet or lower 180 degrees of chamber. I’m being very careful loading these to not make any false contact and again on extraction holding them so the ejector isn’t pushing them into the receiver.

Remington brass prior to firing measure 0.4620 - 0.4625
after firing 0.4675 to 0.4665 with the bulge facing the larger of the two numbers.


Trying to upload some pics. I’ll make a photobucket and link.

http://s1185.photobucket.com/user/ka...rider/library/

<iframe width="480" height="360" src="http://s1185.photobucket.com/user/kamikazidrrider/embed/slideshow/"></iframe>

To check your reloads RO, roll them across a smooth surface left to right looking at the tip of the bullet. If it orbits as it rolls you have run out. You can probably see .005 +

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Originally Posted by Robinhood

To check your reloads RO, roll them across a smooth surface left to right looking at the tip of the bullet. If it orbits as it rolls you have run out. You can probably see .005 +

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Thanks, I should have thought of that. All looks good as far as RO goes.

these pics are all available in the link above, but this should show two rounds side by side. Showing both sides of the projectile and the contact pattern.

http://i1185.photobucket.com/albums/...FEDAFE58C.jpeg

Put an index mark on each case and place it at 12 O clock. Verify orientation of contact to be consistent.

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Originally Posted by Robinhood

Put an index mark on each case and place it at 12 O clock. Verify orientation of contact to be consistent.

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I’m planning doing just that, I was thinking about it last night some. Figured a sharpie held against the case as I close the bolt should orient things? At least I’ll be able to see a little better if the case rotated any?

Let us know hat you find out.

You probably have a couple of things going on. First of all, your chamber is larger than your unfired brass, or is the brass once fired and not fully fire formed? It's possible that when you chamber the case and bullet, it's sitting off center at the bottom of the chamber. This would put the bullet into the lands at an angle, so that might explain your uneven marking. Your chamber might be a bit oversized too. Once you've fully fire formed your brass you can measure your brass and compare to sammi drawing to determine this. Or make a chamber cast and make a direct measurement.

You might be able make a better determination by drilling and tapping the flash hole of your shot brass to fit a cleaning rod. I use a cheap 3 piece rod for this. Screw the tapped case onto the cleaning rod and slide it in the chamber with the bolt removed. Spin it around and feel for any tendency to stick in the chamber. If the case neck is off center, or the chamber is reamed off center this will be apparent, especially if both conditions are present. In that instance, you'll feel a real tendency to jamb in the chamber as the two off center conditions align in opposition.

Cheap and easy to do, and will provide some valuable information.

While your at it, you can seat a bullet into that drilled and tapped case, again mount it on your cleaning rod and push it into the chamber firmly. If it sticks upon retraction, the bullet is in the lands. Seat it slightly deeper and repeat until you can feel no tendency to stick. That is your touching lands dimension. Keep that cartridge intact for future reference.

As for the barrel being off center, try loosening the action screws a turn or two and shift the barrel into alignment and hold while you retighten the screws. Take note of the rear tang position, it should not touch the stock. You can slide a .005 feeler gage around it so make sure of clearance. If it is bearing against the stock on one side, try realigning the barrel/action again to see if you can find a happy position where neither is touching. Torque the front screw to 45 INCH pounds, and the rear to 25. The rear one can be adjusted up or down to tune the stock to the action. If you have a accustock, the numbers will be higher, but same process.

I hope this helps.

Looking at this once again I think someone tried to clean up an issue and ruined the chamber. I picked one up like this of a forum one time. I put the barrel in V-blocks and an indicator in the chamber and got about .008" out of round. The brass bulged like yours.

Thanks a bunch gents. I’ll look into this a little more. However I’m pretty sure something is amiss. I made a ‘witness’ mark on my brass at roughly the 3 O’clock position and inserted a sharpie colored round. I had those pesky drag marks? At roughly the 4 - 10 O’clock position.


Using the same piece of brass I marked it 180 degrees out from the original witness mark and repeated the same. With the same results(4-10 O’clock) which would put those marks on the bullet the opposing side to which the barrel lists. I’m thinking someone got sloppy with a reamer. Maybe I should order some cerrosafe from midway and make a cast. I just don’t want to keep something with tendencies to bulge brass 1.0 thousandths on one side. Likely to prematurely kill brass.

Guess I’ll make a call to savage in the a.m. and see if they’ll make things right. It’s been over a year since a took possession of it, so I’ll see what they say. Or maybe it’s time to rebarrel to 6.5-284.

Would it be accurate enough to determine if the barrel is off it’s axis by placing the barreled action on a flat surface and measuring the distance to the end of the bbl from said flat surface.

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Originally Posted by Texas10

You probably have a couple of things going on. First of all, your chamber is larger than your unfired brass, or is the brass once fired and not fully fire formed? It's possible that when you chamber the case and bullet, it's sitting off center at the bottom of the chamber. This would put the bullet into the lands at an angle, so that might explain your uneven marking. Your chamber might be a bit oversized too. Once you've fully fire formed your brass you can measure your brass and compare to sammi drawing to determine this. Or make a chamber cast and make a direct measurement.

Thus far I’ve been feeding it factory fodder, it really likes 165gr corelokts, although I’ve fed it a box or two of some federal ammo. I’ve been stock piling the used brass, however I think I’ve polished and resized almost all of to this point. I have about 20 fired cases I haven’t touched. These all have the bulge on one side. I’m tempted to buy one more box and inscribe witness marks on it and then shoot to see where it’s bulging. See if it is indeed due to the brass sitting in the bottom of the chamber or another issue. Crazy thing is it shoots about 3/4 moa regularly. That group in my picture is a 300 yard group from this rifle IIRC.

You might be able make a better determination by drilling and tapping the flash hole of your shot brass to fit a cleaning rod. I use a cheap 3 piece rod for this. Screw the tapped case onto the cleaning rod and slide it in the chamber with the bolt removed. Spin it around and feel for any tendency to stick in the chamber. If the case neck is off center, or the chamber is reamed off center this will be apparent, especially if both conditions are present. In that instance, you'll feel a real tendency to jamb in the chamber as the two off center conditions align in opposition.

Cheap and easy to do, and will provide some valuable information.

I really like this idea. I should probably have a machinist drill and tap to ensure concentricity though.

While your at it, you can seat a bullet into that drilled and tapped case, again mount it on your cleaning rod and push it into the chamber firmly. If it sticks upon retraction, the bullet is in the lands. Seat it slightly deeper and repeat until you can feel no tendency to stick. That is your touching lands dimension. Keep that cartridge intact for future reference.

As for the barrel being off center, try loosening the action screws a turn or two and shift the barrel into alignment and hold while you retighten the screws. Take note of the rear tang position, it should not touch the stock. You can slide a .005 feeler gage around it so make sure of clearance. If it is bearing against the stock on one side, try realigning the barrel/action again to see if you can find a happy position where neither is touching. Torque the front screw to 45 INCH pounds, and the rear to 25. The rear one can be adjusted up or down to tune the stock to the action. If you have a accustock, the numbers will be higher, but same process.

Yes, this is an accustock.

I hope this helps.

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Yes this helps. I’m always on a learning quest. In another life I would have been a gunsmith and machinist, although I’m a savage-smith and have done a good bit of other little fixes and adjustments to firearms over the years. I just don’t have the appropriate tools or access to a shop that does, to measure half the things I want to. Outside of owning a pipe wrench I think a micrometer is the only precision tool I own.:cool: J/K.

Your brass has a bulge because it is undersize. The bulge will appear to be off center because it will expand to the weakest side, meaning that the wall thickness is thinner on that side. That .001" difference you measured is from the difference in wall thickness and the way it contracts after firing. Chances are that the chamber itself is concentric, but may have a slight misalignment with the bore.

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Originally Posted by sharpshooter

Your brass has a bulge because it is undersize. The bulge will appear to be off center because it will expand to the weakest side, meaning that the wall thickness is thinner on that side. That .001" difference you measured is from the difference in wall thickness and the way it contracts after firing. Chances are that the chamber itself is concentric, but may have a slight misalignment with the bore.

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So, I was curious about that. What are the tolerances on Brass sizing per Saami? And again what are saami tolerances in chamber size? Seems like stacked tolerances could play a part in this. I would agree that a slight misalignment might be party to what I’m seeing. If you look at that picture of the brass(in the micrometer) you can see where the brass has expanded, that expansion line should be perpendicular with the axis of the chamber no? As you can see it has a couple degree offset from being perpendicular. Either there is a slight misalignment or there is a slight eggshape to the chamber? And possible slightly undersized brass. I suppose I should measure the distance from case head to the “bulge” and do a little math to determine what I should be seeing.

SAAMI spec for the case head is .4618-.4698". Spec for that area in the chamber is .4708-.4728". Your brass is right at minimum, and I'll bet the chamber is at minimum, but as you can see, the tolerance on the case is .008", while the tolerance on the chamber is only .002". Chances of the chamber being egg shaped is not bloody likely, but it might give you that impression looking at the fired case. While it may look alarming and unnatural, what you have is still within industry specs.

If you're going to try the drill and tap of the flash hole, it's not important that it be absolutely inline with the case. I drill on a drill press, and tap by hand using a cordless drill set to slow speed. If your tapping job is a little off axis, your rod will be a little canted. Not a problem since what you are going to be doing is inserting the case and withdrawing it several times to check for dragging, rotate 90 degrees and repeat until you've gone 360 degrees. Just don't screw the rod in tight to the case, let it float a bit.

If your chamber is slightly out of round, and your case neck is running out a few thousandths, you'll feel the stack in tolerances cause the case to tighten up as you slide it in and out and rotate the case through different positions.

Sharpshooter; I’m not entirely sure the chamber is out of round, at least not much. I was thinking more along the lines of off the axis of bore maybe. I’m definitely making contact on just one side and it’s opposing the direction the bbl is skewed, or appears to be skewed. I just don’t like seeing the contact when I’m well off the lands. Just doesn’t sit good with me.

I’ll let you all know what the outcome is.

I haven’t used cerrosafe before, any advice if I go that route?

Texas10, ok that makes some sense. This is using a fired and not sized brass correct?

It definitely could be off axis, I've seen more factory barrels with chambers off axis than ones that are straight. Out of round....not bloody likely. That would be hard to do deliberately. Honestly, I wouldn't lose any sleep over it. I had a 6 BR dual port that only showed 2 land marks on one side. It would shoot in the .2's @ 100, and 2" @ 500. Go figure...

If you like the way it shoots, leave it alone and shoot. If you think it is a pig for accuracy then consider sending it back to Savage for a new barrel (or have a competent gunsmith fit one).

As far as using the stock to measure angle of the barrel, that's the wrong place to start.

Use a GOOD straightedge up against the side of the receiver and check both sides to see if the barrel is aligned with the receiver. If it is aligned properly, then reshape the barrel channel in the stock until it is to your liking. If it is not aligned with receiver then again, send to Savage or have someone else fix it.

FWIW, the alignment issue is not limited to factory rifles. A guy showed up at the range with a custom chassis rifle that he said cost $5k (the scope was a $2k version). He could not get rounds on paper before he ran out of windage (but they all hit in a very small group on the backstop :) ). You could sight down the receiver and see that the barrel was canted off to one side.


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