I would like help on some questions with tuning a new rifle.

Background:
I recently obtained a Ruger Hawkeye in 338 Win Mag. The bedding had a little wobble to it and the barrel touched the left forearm.

So before firing the first shot I epoxy bedded the rifle. A 1/4" 3.5" long all-thread was epoxied into the wrist from the tang.
The barrel channel and sides of the stock around the action were sanded until the action would sit in the wood without wobble.
Then a 1 1/4" long 1/4" all-thread was fit for the recoil platform under the action.

This bolt was epoxied into the platform and the recoil platform was fully epoxied. The recoil lug is fully encased by epoxy (although the bottom, sides and muzzle-side of the lug had pieces of electrical tape so that the seating of the lug against the recoil platform would be primary and stress-free.

The epoxy flowed under the barrel so that the first 1/2" of the barrel channel how has a very clean, small support pad, while the rest of the barrel is free floated. (PS: the white flecks are carwax dust. The all-thread is fully covered by epoxy.)

Scope mounted: Nikon Inline 3-9" in Ruger rings. the mounting is solid without any play or slippage after the first range session (27 shots. After every three shots a wet patch of Hoppes elite was placed thru the barrel followed by a dry patch.)

Problem and questions.
One of the loads in load development printed a 9" triangular group, and also some straight vertical groups of 5" and 6.5". These were very careful handloads that also produced expected velocities according to the reloading manuals. Shooter error might account for 1/4" or 1/2", not 6". Likewise a breeze might have contributed 1/4" to the 3-shot groups. But that doesn't describe a straight vertical group of 6". Best group of the day was 1.1" and 1.75"

1. Could an epoxy barrel pad cause such irregularity?

2. Have anyone ever seen a Nikon scope produce such instability? I might try another scope in Nov to see if this solves the problem.

3. Other ideas?

Thanks.

Every single Ruger I've ever bedded had the recoil lug FULLY bedded, no gaps, it requires a full bed to sit in due to the angled screw attachment.
I also pillar bed the stock, this also gives a positive bed for the stock to pull into the action.
There's no fear of the lug binding, as the screw releases the action cannot get 'trapped' as can happen on a straight recoil lug.

I would hazard a guess that you torqued the action screws during bedding, giving a stressed bedding job. I use surgical rubber bound tight around the stock and action, never had a problem doing this in 20 years.

As to your problem, I think you need to re-bed, remove the all thread, see no need for that under the recoil lug, and bed the entire action along the mag well. This is where Rugers can bend.

Cheers.

I always had the best luck bedding the first 2 or 3 inches of the barrel in front of the action a half inch isn't enough.

With groups that size I would be replacing the scope before I did any thing else. Just to eliminate that as a problem

It would seem to me that different bedding techniques might explain large variations in group sizes but not nearly in this order of magnitude. I might first try easy fixes. If it were mine I might do all my test shooting with quality factory ammo so as to eliminate any possible hand-loading issue. I would then try recrowning the barrel which is any easy home project. Then change out scopes. By doing this one step at a time and shooting for results you'll have a pretty good indication whether rebedding is the solution. Good luck...

quote:

Originally posted by p dog shooter:
I always had the best luck bedding the first 2 or 3 inches of the barrel in front of the action a half inch isn't enough.

With groups that size I would be replacing the scope before I did any thing else. Just to eliminate that as a problem

Yes . . . I'd probably check for scope and mount screw tightness, and if they were okay, I'd swap the scope out.

The scope and mount screws were all tight throughout the shooting. Also the stock action screws.

During the bedding the front action screw was used for the bedding but was not torqued it was engaged until resistance was felt and then backed off so as not to stress the action. In fact, the finished epoxy allows the action to sit in the stock with zero play. It is as stress-free a bedding as I have done, even when using rubber ties or masking tape during the curing time.

As for the cross bolt, I will definitely leave that in place. I've busted two stocks with a 500AccRel where the recoil platform cracked under recoil. Only by judicious reinforcement have I been able to produce a good third stock for that Ruger rifle.

So yes, first check needs to be a different scope.

On ammo, most of the rounds were with a 200 grain CEB MTH, which are new for me and use a different kind of design with 'seal tight'. The 225 grain TTSX's produced the 1.75" groups.

Based on the TTSX groups of 1.75, I'd say the rifle doesn't like the 200 grain CEBs.

Personally, I'm with 416RigbyHunter on the recoil lug. I had a similar problem with a Weatherby Vanguard. The recoil lug had space at the bottom because I used electrical tape and when I tightened the action screw it torqued the receiver. It was pretty obvious when I held the forend and barrel in one hand while tightening and loosening the action screw with the other. Upon loosening the action screw, I could feel the barrel springing away from the forend. I would rebed and bed the tang area as well. No need to fully bed the length of the action.

With respect to glass supporting the barrel, I've had rifles shoot well with no barrel support all the way to two inches of bedding. I don't think it will matter in a hunting rifle. Unless, you are long range competition shooting. In that case, I believe barrel support could induce some vertical as the barrel heats up.

I understand you may not want to use the 225 TTSX but if you do, here's a load with it that has produced submoa accuracy in four of my 338s. You'll just have to find the optimum seating depth for the rifle. 67.5 grains IMR 4350, Winchester cases, CCI250 or Federal Gold Medal Match primers. For Norma cases, increase the charge weight to 68.5 grains IMR 4350. If this load doesn't shoot submoa in your rifle, you have bedding or other problems. Good luck...getting the rifle to shoot well is half the fun and unfortunately, all the frustration!

I know you well enough to doubt anyone can best your extensive knowledge of the issues at hand.
My first thought was a shifting scope reticule or loose mounting is the best possibility for the groupings you describe. That is until you mentioned the smaller groups with a different bullet. I think your bedding job fine and doubt any problems related to it. I suspect your barrel does not like those particular bullets. I have a Douglas barreled tang M77 in 257 A.I. which has always been MOA with most loads but averaged 4"-5" with the first Barnes X 100 gr. bullets and no powder or bullet seating changes improved it. Not judging the bullet; this barrel and bedding didn't like them.
Concerning M77's, at least the tang safety first models. A highly respected smith with much more experience then myself with M77's told me that most of the problems he found with rifles that were brought to him with accuracy problems were found to have chambers cut off center, usually fixed by a barrel set-back and re-chambering.
I enjoy your posts, Dr. R

How did it shoot before you did all the work?

I'd try different bullets and powders. I had a 375 that shot 9" triangles with 300 gr Accubonds and then 1/2" groups with 300 gr TSX - all the other bullets were in between.

Start with some inexpensive flat base bullets and see how they shoot - I'd recommend some Sierra 225 gr Pro Hunters and then go with a published max book load with H4350. This should shoot well. If not, you are in for a long haul on tuning this bad boy.

OK--I went to check exact loads and add pictures.
It turns out that the 200 CEBMTH turned in a 1.1" group as well as a 5" vertical group, and a 9" group.

Below is the group with
.338" 200gn MTH 72gn IMR4451 once-fired Win brass.

The group is 9" The group data is on the left and a heavy line contacts the three shots!!!! That is a real group and the sight pictures were solid in firing. Velocity was 2970fps.

Equally outrageous is the following group
200gnMTH R-17 72 grains for 3060fps and a 6" vertical group.

The point of aim in the above picture was the large certaer target, so the shots all hit 3" left at 0, 5, and 6.5" above aim. I did not record the order of shots.

But now for the surprise.
Here is a load
.338" 200gn MTH 72gn IMR4451 in new Hornady brass.

Velocity is 3008 fps. It is a promising load. I do not believe for a minute that the different brass made the difference in a 9-inch group and a 1.1" group.

So yes, the TTSX 225 grain groups of 1.75" and a two shot group of 1" did not produce a crazy group. But the CEB bullets produced both crazy groups and reasonable groups.
Here is the 3-shot 225TTSX group

The group was basically horizontal 1.75" 225TTSX at 2828fps (69gn R-17 in new Hornady cases)

So I am guessing "scope" or "still unknown factor"

I should add that after several of the groups I would adjust the scope to get closer to a reasonable point of aim. Nikons have always tracked very well with me but this time, apparently not. for the record, I would routinely tap the rifle on the butt to help the scope settle after a change, a habit I developed 30 years ago. I cannot remember if I did that after each change 2 days ago. Again, Nikons have always tracked so well that I would not have considered it necessary.

I also remember that one or two of the scope adjustments missed a clicking sound, or produced a muffled click while counting clicks. I thought it was just my lack of attention or uneven turning motion at the time, but now I'm not so sure. This mystery will await late Oct to see what a new scope will bring.

quote:

Originally posted by 416Tanzan:
OK--I went check exact loads and add pictures.
It turns out that the 200 CEBMTH turned in a 1.1" group as well as a 5" vertical group, and a 9" group. (The 11" was an error of memory and judgement, pre-measurement.)

Below is the group with
.338" 200gn MTH 72gn IMR4451 once-fired Win brass.

The group is 9" The group data is on the left and a heavy line contacts the three shots!!!! That is a real group and the sight pictures were solid in firing. Velocity was 2970fps.

Equally outrageous is the following group
200gnMTH R-17 72 grains for 3060fps and a 6" vertical group.

The point of aim in the above picture was the large certaer target, so the shots all hit 3" left at 0, 5, and 6.5" above aim. I did not record the order of shots.

But now for the surprise.
Here is a load
.338" 200gn MTH 72gn IMR4451 in new Hornady brass.

Velocity is 3008 fps. I do not believe for a minute that the different brass made the difference in a 9" group and a 1.1" group.

So yes, the TTSX 225 grain groups of 1.75" and a two shot group of 1" (neither pictured here.) did not produce a crazy group. But the CEB bullets produced both crazy group and reasonable groups.

So I am guessing "scope" or "still unknown factor"

Long time ago I was having a similar problem with a Ruger M77-MKII stainless steel rifle. The action was mounted on a Hogue Rubber Overmolded stock. Anyway, I was ready to replace the scope, until I read an article about how to thoroughly clean the barrel first, so I proceeded to do that. I brushed and brushed the barrel to remove all copper and powder fouling, and went back to the range. Back then I was shooting 230-grain Lubalox-coated Winchester FS factory ammo, and when I shot it again at the range the first two bullets at 100 yards printed 1/2" from each other. The third one printed about 1" to the left from the other two.

I would thoroughly clean the rifling before making any load changes, and fire the rifle on a cold barrel. I would do this, just to see how the first three shots print on the target at 100 yards.

When breaking a new barrel I always clean it first, then cleaned it between every two or three shots until I hit 20 or so rounds. Later, I always clean it before each group of 3, and shoot on a cold barrel.

Ray's comments about the new barrel are good.

I do have a question. How did you bed the balance of the action area, especially the rear screw lug area.

Capo--
I haven't done the rear recoil screw yet. I was planning to epoxy-pillar it. However, I ran out of time and figured that it was a moot point for getting started on the rifle. Wood compression in walnut normally takes a period of time and a lot of use. Neither was true for the break-in debut two days ago.

Ray--on cleaning--yes, I cleaned the rifle before first firing. I didn't want to trust whatever the factory may have left in the barrel.
However, between groups I only did the light single pass of a wet Hoppe's Elite patch and a dry patch. The idea was not a complete cleaning, but a reduction of carbon build-up for comparable groups. Yes, when retesting I may try a more rigorous cleaning between groups.

Tanz,
I don't believe you'll ever reach consist accuracy with a partially bedded rifle.

quote:

Originally posted by capoward:
Tanz,
I don't believe you'll ever reach consist accuracy with a partially bedded rifle.

I would agree, though I have a question.

Would an epoxy-pillar rear tang with corresponding bottom metal bedding (including an epoxy front angle pillar be a full bedding?
Or are the sides of the action necessary, too?


Many a year ago a gun shop/gun smith told me not to bed the sides of the action.So I have always two-point bedded since then, front recoil platform, then, or previously, the tang bolt. (Big bore rifles excepted, since they need a barrel lug bedding as a third point --- and all of these without any stress, play, or torquing as the screws are tightened.)

PS: Here is a pic of the current wrist-bolt as it sits down behind the tang bolt hole.

The picture does not clearly show the full diameter of the 1/4" wrist-bolt since it angles into the junction of the rear tang wall and only partially fills a little toward the tang stock hole.
There is still room to drill out 3/8" for an epoxy pillar. (Apparently aluminium pillar-bedding developed from benchrest shooters using epoxy-pillars to prevent compression or to restore stocks that lost accuracy overtime.)

Tanz,

I'm not sure about an "epoxy pillar" for the rear screw lug; I've never done solely that.

I've always done a complete glassing of the action, the first 3" of the barrel, and free floating the remaining length of the barrel although that section of the barrel channel is also glassed.

Of course I've traditionally used M98 Mauser actions. Of course when properly done, the front lug meshes with the one piece bottom metal screw spacer providing a full metal to metal fit.
For the rear screw, I've used a metal ferrule spacer sold by Brownells that closely matches the factory Mauser military stock spacer:
http://www.brownells.com/gunsm...11-098-983-3557.aspx

Now a days I'm spoiled by using B&C Medalist synthetic stocks with a full aluminum bedding block with my M98 Mauser barreled actions; it eliminates the need for the rear ferrule screw spacer.

quote:

Originally posted by 416RigbyHunter:
Every single Ruger I've ever bedded had the recoil lug FULLY bedded, no gaps, it requires a full bed to sit in due to the angled screw attachment.

This. Bed it without any tape on the recoil lug. Tighten down the front and rear action screws using moderate pressure and walk away for 24 hours.

quote:

Capo:
Now a days I'm spoiled by using B&C Medalist synthetic stocks with a full aluminum bedding block with my M98 Mauser barreled actions; it eliminates the need for the rear ferrule screw spacer.

when researching pillar bedding options I ran across a youtube where a person recommended milling out the aluminum block for a better fit. He claimed that the bedding block and the action fit are never as precise as an epoxy bedding job. However, since I don't have easy access to a real workbench, let alone a milling machine drill set, I would probably be content to go with the bedding block alone and leave the re-bedding to the benchrest crowd. For hunting I am sure that you are more than good to go.

quote:

Snowwolfe:
Bed it without any tape on the recoil lug. Tighten down the front and rear action screws using moderate pressure and walk away for 24 hours

so should one bed the sides of the action, around the bolt release, safety, and trigger, too? Remember I'm not trying to get a 0.7" rifle down to 0.4", I trying to figure out why that 6.5" straight vertical group happened (see pic below), and how to get a load that is 0.75" to 1.0". That will hunt just fine out to 400, even 500 yards.

Here is a pic of another outrageous group.


This group is 5.2" inches and very vertical. The first two shots looked like I might have found a decent load, but the third shot printed four inches higher instead of between or beside the first two.
What caused this?
How do I correct it?
Do scopes do such vertical shifts?

Vertical stringing can be caused by:

a. The barrel's lower surface touching the stock and the barrel warms up. This can also happen if one is supporting the rifle at the forend.

b. Sometimes this also happens if one does not pay attention to one's breathing when firing the rifle.

c. Variations in the powder charge of the loaded ammo. Can you use some factory ammo?

What I would do is to do a full-bed job and be done with it, or just use another stock for the time being.

My experience with Barnes bullets has never been good. Barnes' techs. have advised me to jump the bullets 50 thou. off the lands. For an old benchrest shooter, that is a lot!
My experience with verticle groups means the cartridge is looking for more powder.

quote:

Ray:
a. The barrel's lower surface touching the stock and the barrel warms up. This can also happen if one is supporting the rifle at the forend.

Can a warm barrel touching a "pad" just in front of the action account for a 6" vertical jump?

quote:

Pegleg:
My experience with verticle groups means the cartridge is looking for more powder.

I'm game for more powder, but the charges were producing typical max velocities for a 338WM around 3000fps with 200grain bullets.

WITH GROUPS USING THE SAME LOAD VARYING BETWEEN 1.5" AND 6+", MY FIRST THOUGHT WOULD BE SCOPE.
(SORRY DIDN,T KNOW I WAS CAP LOCKED)

Agree. That big spread in vertical stringing is weird, and not normal at all. But I doubt that the problem is caused by the action or the barrel (?).

Anyway, the best point on the stock to support the rifle at the range is not too far in front of the trigger guard.

You may have to start all over from the beginning:

a. Identical powder charge, brass, primer, etc. for all the rounds to be fired

b. Thoroughly clean and cool barrel before each group or 3

c. Suspect a bad scope

d. Suspect a bad bedding

d. Follow the instructions to the letter on how to tighten the stock to the action. Placing the rifle on a table with the muzzle pointing up: drive all the screws finger tight only, then torque to top screw to specs.

Now start tightening the trigger guard screws a little at a time until the bottom screw (behind the trigger guard) is tight to specs, but the middle screw (in front of the trigger guard) is just snug. The idea is for the top screw to be torqued to specs (read the manual), the bottom screw (behind the trigger guard) to be tightened to specs, but the middle screw not to be too tight.

I bed a lot of Rugers, the biggest improvement, especially with wood stocked models, is the use of aluminium pillars.
The one's available from Brownell's work, but, they need some help in my experience, as they can slip in the epoxy over time. I turn a 1/8" wide 1/16" deep groove in the front pillar, and 3 grooves of the same in the rear pillar.
I bed and do the pillars at the same time. Some find it easier to do it separately.
As I said, the best results have always been with the recoil lug fully bedded around the pillar.
Now that I know the bedding job wasn't finished, I believe this is your problem.
The tang is just as important as the recoil lug.
I also bed the ENTIRE straight section of the knox form. If this happens to be 2", then that's what gets bedded. My CZ's have small knox forms and heavy barrels, so I bed them the same, just the knox form.
I feel that if start again, bed the recoil lug fully, the tang and add pillars, you may find a great shooter lurking in there somewhere.

Cheers.

quote:

Originally posted by 416Tanzan:

quote:

Snowwolfe:
Bed it without any tape on the recoil lug. Tighten down the front and rear action screws using moderate pressure and walk away for 24 hours

so should one bed the sides of the action, around the bolt release, safety, and trigger, too? Remember I'm not trying to get a 0.7" rifle down to 0.4", I trying to figure out why that 6.5" straight vertical group happened (see pic below), and how to get a load that is 0.75" to 1.0". That will hunt just fine out to 400, even 500 yards.

I always bed the entire action just because I prefer a snug fit to help keep the debris and water out. But as I stated previously Rugers do not require any tape under or around the recoil lug. After the action is removed make sure there is enough clearance behind the tang.
Just for kicks, look at the crown of your rifle with a magnifying glass to make sure you don't see any nicks.

Glass bedding can be weird. I seen some rifles that were so poorly bedded it was shocking, yet they shot well. Then I seen perfect looking bedding jobs and the rifle wouldn't hold 5 MOA.

Thank you.

Because of the vertical weirdness, I am thinking that I will sand down the barrel support pad in addition to trying a known scope and bedding the rear and bottom metal. Our Tikka 338 in Africa has a fully floated barrel and shoots great (0.7--1.0MOA).

Maybe I missed it, but I did not read/see the rifle having had a trigger job.
If not, that is what I would do first AND then follow the advice here.
Good luck.

Given you said the scope isn't tracking right, I would suspect the scope is the issue, period.

Put a new scope and mount on it and see if this all goes away.

9" groups? Only rifles I had that did that were bad scope, bad mounting of scope and an absolutely shot out barrel that did not show bad grouping until you got past 100 yards.

quote:

Originally posted by crbutler

9" groups? Only rifles I had that did that were bad scope, bad mounting of scope and an absolutely shot out barrel that did not show bad grouping until you got past 100 yards.

Try shooting a rifle with a damaged crown, or one that has the stock split behind the recoil lug

This is how to bed a Ruger

But I always bed the entire chamber...and I use fiberglass in my epoxy

Here is a Kimber Montana I'm working on now

the biggest mistake I see in most sometime stock makers or glass bedders is just because the barrel is pressing on wood on one side or the other, they start opening up the barrel channel, when the problem most of the time is pressure on the opposite side of the tang pushing the barrel to one side or the other, and when that gets fixed the barrel pops back to center and you have this huge gap on one side of your barrel channel, and all you can do it fill that in with glass and a big line of glass on a stock is hanious.

Glass and piller beading isn't a cure all, its a method to correct only certain problems, otherwise it can create problems..

I like to bed a gun tight, then shoot it, if that fails I will 3 point bed it, two inches of barrel tight, pressure on the forend, glass the tang; shoot it and if that does not work I will free float the barrel and leave it tight two or three inches under the chamber and free up the forearm only enough to all me to blow smoke thru it, it will then be freefloated..Keep in mind a rifle cannot rock in the bedding and be expected to shoot its best.

I do it in this "order only" because you can take wood out but you cannot put it back.

Before I glass bed a rifle I get it to shooting first with inletting the wood, adding and subtracting shims or whatever, then I know "how" to set it up in glass..

Ray, good call. Your concern is/was my concern.

The first thing that I did was to relieve the action on the opposite side from where the barrel touched the stocked. Also the action inletting needing some sanding to get rid of some rough spots. After the action was clean I worried about getting the action stable, without any wobble or rocking. this was coupled with cleaning out the barrel channel at points. I was very happy with the finished seating and bedding. Which is why I will try a new scope in four weeks when I'm joined up with the rifle again.

If the barrel was touching the left side of the stock, I wouldn't waste time with it. Toss that stock and get a Boyd's :

http://www.boydsgunstocks.com/...12&Shape=04&Finish=1

I doubt that, if it were so, everybody would use Boyds stocks! using another stock isn't his problem, bedding is..All stocks must be bedded properly, and factory stocks are built to fit all, sometimes that just doesn't work..sometimes Boyds don't work to claim otherwise is just wrong.

I have had 12 Ruger 77 in 338 win mag. They all shot very good under an inch at 100 yards with factory loads. I put a boyds laminated stock on one and shot 3/4 " at 200 yards with Remington 225 gr that use to be loaded with 225 grain speer bullets.That boyds stock is awesome and recoil was way less too.The barrel is thicker on the 338 win mag and is way more stable .I have shot tons of clover leaf groups at 100 yards with Winchester 200 gr power points also .I love those Ruger 338 win mag model 77 I have hunted with them 30 years awesome guns for the money !

dgr416--

That's nice to know. I've only had five 338WM's, a Win post-64 70, couple of Rugers and a couple of Tikkas. They were all able to shoot under MOA with tinkering and bedding, even the light, whip-barreled Tikkas. So I am expecting the newest Ruger 338WM to do its paces later this month with a new scope.

I have two .338s at the present..One is full blown custom MAUSER that I built..I also have a Ruger African model, and its been my go to rifle for several years now..3 elk to its credit so far and the closest shot was 329 yards, its my lucky rifle..shoots under and inch with about anything and everything to the same POI..which is what I strive for these days..One couldn't get that done 30 plus years ago, you were damn lucky to find a rifle that would shoot and inch in those days. Back then most of my guns shot 2 to as much as 4 inches at 100 and only with one specific load as a rule. Funny thing is they still worked fine in the field. That's when I learned that I could wiggle on as well as I could wiggle off on a big ole bull elk or Mule deer buck.

quote:

Originally posted by Atkinson:
I doubt that, if it were so, everybody would use Boyds stocks! using another stock isn't his problem, bedding is..All stocks must be bedded properly, and factory stocks are built to fit all, sometimes that just doesn't work..sometimes Boyds don't work to claim otherwise is just wrong.

I recommended Boyd's based solely on price for this project. It seems there is an inherent budget in trying to salvage the warped stock which is beyond repair in my opinion.

The Boyd's is a very good platform to START a careful and meticulous bedding job. If properly bedded, it can give many years of accurate shooting if handled properly and maintained.

The only exception is probably Alaska, where ANY wood stock; including laminate's, succumb to the moisture extreme. But other than Alaska, a Boyd's is as good as any other choice if properly bedded and the Classic can even be ordered with an adjustable comb for a few dollars more!

There was an excellent DVD on 6mmBR.com which showed bedding a rifle to bench-rest standards. This included pillar bedding for perfect bottom metal fit, complete action bedding and free floating. I can't find it now but it was about $60.00.

Found this though :

http://www.accurateshooter.com...at-laminated-stocks/

Corey

http://www.boydsgunstocks.com/...mNumber=4VB5510041ZZ

Adjustable comb; $60.00 (third from the bottom option)

Well, a little update will raise further questions.

First, I epoxy bedded the tang with an epoxy pillar.

Here is the top picture of the rear screw hole:


You can see that I left some wood as a point of reference and stabilization.

Here is the view from the bottom, where the epoxy pillar is more visible:


the 3/16" screw now sits in a 3/8" epoxy pillar and the screw-hole itself has been drilled in order to remove any grooves from the screw so that it will not bind when being tightened.

Secondly, the scope on the rifle was replaced with a duplicate Nikon Inline 3-9x40.

A trip to the range allowed my to try several hand loads, expecting some tight groups.

* * *

But alas: most groups were 2.5-3" with a couple of groups at 5"!!!!!

That is horrible and unacceptable.

I checked the crown just to make sure that a little nick was not visible. Everything looked clear and pristine on the crown.

So what is going on?

This will await a couple of weeks till when I get another chance to fire some rounds. In the meantime, I have removed the little 1/2" epoxy pad that cradles the beginning of the barrel where it emerges from the receiver.

When the action was bedded the forearm was kept at the proper reference point by putting masking tape around the barrel at the forend tip. After bedding, the masking tape was removed. However, I suspect that the barrel was then resting on the epoxy pad in the barrel trough with pressure from the weight of the barrel. My current guess is that this pressure was changing from shot to shot as the barrel would sit in that epoxy cradle. I had one rifle many a year ago that did not like a barrel-support-pad. So in two weeks I will see if I've solved the problem.

Otherwise, I can't think of what to do except re-chamber or re-barrel.

Any more ideas?