Accuracy Issues (30-06)

[ferrum]

Long time lurker first time poster -- please move if this is not the correct sub-topic. The folks who frequent here seem to have a good idea on what it required for consistent accuracy.

I purchased a Rem 700 SPS 2 years ago and have had accuracy issues since day 1.
With hand loads, it would routinely print 3 out of 4 rounds in a sub 1" cluster but one of the 4 would be a 2"-3" flyer.

Figuring it was the cheap plastic stock, I replaced it with a B&C Alaskan and glass bedded the action.
This reduced the distance of the flyer, but 1 out of 4 shots is always a flyer.

I have worked up a variety of loads for this rifle (easily 30 or more over the last 2 years; with 150, 165, 168, and 180 grain bullets of varying manufacture and 3 or 4 different powders).
I have used 2 different scopes and all bolts/screws have been torqued to manufacturer specs.

The lighter bullets (150 gr) consistently throw the flyer the farthest (2" group size) and the heavier bullets (180 gr) group the best (~1.5" group).

I do not believe the issue to be me -- as my other rifles consistently group under an 1" at 100yds.

I would like to use 150 grain bullets -- as this rifle was purchased as a dedicated antelope rifle.

Now to my question.
Does this sound like it could be an issue with the crown?
If not the crown -- what would you suggest that I look at next?

I see no reason why a modern rifle should not be capable of 1" groups at 100 yds but am unable to achieve that with this rifle.


Thanks for your time.

[Wiggity]

A strange problem indeed since the problem is not consistent. Especially if its fine with heavier loads and not with lighter loads.


1 in 4 is a flyer, that leads me to think it is not a problem with the gun. Reason being: how could a barrel possibily be consistent with 3 rounds and not consistent wit the fourth?

[encorehunter]

Is the flyer the same round every time? How long are you waiting between shots? If it is the 4th round consistently, I would say the barrel is heating and causing contact to the stock. Is the flyer hitting in about the same spot every time? i.e. 3 o'clock?

[Zombie Steve]

I'm not sure what the answer is, but my gut is telling me it's not the rifle (is this the only one you load .30-06 for?). It doesn't sound like a crown issue... those tend to just throw bullets everywhere every time.

Are you squaring up your dies? I'd look at bullet runout as the first easy thing to check. You might find some are perfectly concentric and some are .006" off center. That will cause a flyer. Have you put the loads over a chrono? Are they consistent? Are you neck sizing only? What brass / powder / primer combo are you using?

When you pull out the bolt, do you have even wear on all four sides of the locking lugs? The action may need to be trued up / blueprinted.

How's the trigger? Is it one of the old lawyer-proof kind?

[ferrum]

It is not the 4th shot every time. Any one shot could be the flyer. Direction of the flyer seems to, primarily, vary between 9 and 3 o'clock.

My test procedure it to shoot 1 fouling shot from a clean barrel.
I then shoot a 4 shot group. I chose four for load development in case I noticeably pull a round -- it gives an extra shot to see if that particular loading has potential and warrants another test.

I let the barrel cool, between strings, until it is luke warm to the touch.

This is the only 30-06 I load for, I set the dies per RCBS instructions. Should I be doing something different?
In the past I full length resized my brass -- but I now only neck size.

I have not chronographed my loads yet. I just purchased a chrony.
I do not own a concentricity gauge. Maybe I should.

Brass: Winchester or previously fired Hornady (says Frontier on the case)
Powers: Varget, IMR4831, H414
Primer: CCI large rifle BR
Trigger is the new adjustable Remington trigger. Set at about 3.5 pounds

Looking at the bolt now. No, It does not have even wear on all sides of the locking lugs. As a matter of fact -- they are not even close to having the same wear pattern. Maybe that is it? Any idea on what I am in for ($$$) to have it trued up/ blueprinted?

Thanks.

[C Ward]

Sorry to say but if it isn't the same shot the goes wide every time the most likely cause is shooter error .
Lighter weight hunting rifles are way less forgiving of position errors and are harder to shoot consistently .

[Zombie Steve]

As long as you can tell it's making some contact on both sides of both locking lugs, I would look for other possibilities.

Rifles tend to settle down after a few strings. Try shooting more fouling shots, or just don't clean your barrel next time. I never hunt with a clean barrel for this reason.

If it's only happening with .30-06, and this is the only gun you shoot .30-06, it might be the dies. When you get to bullet seating, get the die set where you want (most likely no crimp - are you crimping? If so, stop), but before you tighten the locking ring, stack some small flat washers (coins if you have to) on top of your shell plate and raise the ram. When it contacts the die, you'll see the die move / straighten out. Lock it down with the ram raised. That tends to solve most any slop / runout I get from various dies. Heck, if you feel like it, you're welcome to check your rounds on my concentricity tool. No need to drop the money to eliminate that one factor.

Also - I always shoot at least 7 of a given powder charge while I'm doing load development. It tends to give me a better idea of when I'm screwing up vs. the load itself, and it definitely helps eliminate the good 3 shot group that's a fluke. I suppose it's possible that you just haven't found the load it likes yet. I'm not sure how long you've been reloading or if you have a process that's worked for you in the past... if so, keep with it.

If you really want to go deep down the rabbit hole, start separating your bullets and brass by weight. Get everything as consistent as possible. It shouldn't matter much at 100 yards, but it certainly doesn't hurt. If you've never done this, you'll be surprised how much bullet weights and brass vary. All part of the equation.

Hope this helps.

[SA Friday]

My money is on brass prep. First, use one brand brass for testing. Mix the brass, all bets are off. Second, short of Lapua, the primer hole was punched and not drilled. If you are not deburring the inside of the primer hole, you may have enough material in the way to cause the powder to burn unevenly. The primer may be lighting off the powder on one side of the case and not the other, initially. I had this problem when I first started reloading HP rifle rounds. Second, check the case OAL and make sure all the test rounds have been cut to the same length. These two things will alleviate the majority of the inconsistency you will see from the case now that you are not full length resizing.

Stick with the H4831, or even better, H4831sc. Same powder with a shorter rod cut. I find the sc powder was more consistent in my 30-06 loads, but they should both work well enough to achieve sub-MOA groups in the rifle.

Measure the throat of your chamber and make sure you are not loading an OAL that is jumping the bullet too far.

When shooting the groups, I recommend shooting 5 rounds of each test load at a single target. Then mark the target with the bullet, powder, OAL etc. Save them, photo them and post here. What you want to see is a consistent decline in a circular pattern. Then it will stay start to open up in a split pattern, then it will group in a consistent opening pattern. Mark any called shooter induced fliers.

Some rifles do benefit from having the receiver trued and the barrel reset. $3-500. Once trued, the rifle will shoot better. If it was shooting .5" groups, I wouldn't recommend this. As it is, it may very well tighten everything up. Try the above first.

Oh, ya. Stop brushing your barrel clean... This may be as much of a problem as you may think cleaning it is fixing. Short of shooting corrosive ammo, over cleaning the barrel is simply a bad idea. I killed a 7mm barrel with over cleaning. Short of getting dirt or sand in the barrel or seeing an obvious issue with accuracy going from good to bad, I don't brush my rifle barrels at all after shooting the first five rounds through it. You are doing more damage than good after that.

[Zombie Steve]

Flash hole uniforming... I knew I was forgetting something.

I didn't catch he was using mixed brass. That'll drive a fella nuts.

[ferrum]

Thanks guys.
Will give those suggestions a try.
To be clear -- I am using 2 types of brass. Winchester and Hornady. But they are separated for load development. I.e. same brass for a given load.

I do use the h4831sc for my winmag and I agree that it is a great powder. But there are no loads for 150 grain bullets using h4831sc. 150 would be my preferred bullet weight -- but I may just go with 180s as they do group much better.

I have been reloading for about 6 years. But am always willing to learn new tricks. This is my only rifle that gives me fits in the in the accuracy department. It is quickly becoming my white whale...

[SA Friday]

Well, I will tell you the only way I've ever gotten 150s to shoot worth a damn out of my 30-06 was to back the powder charge way back and drop a lot of velocity to find an accuracy node. The 165's shot like they had eyes and towards the higher end of velocity. If you can get the 165s to group and get the velocity out of it, thats a much better option than fighting the 150s.

[ferrum]

Great thanks. I am going to head out today and get a flash hole uniformer tool and hit the bench again.

[Zombie Steve]

Well, I will tell you the only way I've ever gotten 150s to shoot worth a damn out of my 30-06 was to back the powder charge way back and drop a lot of velocity to find an accuracy node. The 165's shot like they had eyes and towards the higher end of velocity. If you can get the 165s to group and get the velocity out of it, thats a much better option than fighting the 150s.

I'll second this thought. I found a really accurate load with 150gr. grand slams and IMR4320 (about the same burn rate as Varget), but it was on the low end (just short of 2,700 from a 22" barrel). Still, two shots went completely through a mule deer broadside. It didn't fill the case very well. Overall, I wouldn't hesitate to shoot another deer with it, but I wouldn't be crazy about long range shots on pronghorn (mainly because of the flat base bullet).

For a dedicated pronghorn load, I'd look at IMR 4350 and a 168 grain Nosler Ballistic Tip. Just my 2 cents adjusted for inflation.

I think he / we were talking about a flash hole deburring tool, not the uniformer... They do two different things.

[ferrum]

I was thinking this:
http://www.lymanproducts.com/lyman/case-prep/flash-hole-uniformer.php

[Zombie Steve]

That's the one you want.

[Hoser]

The KKM version has a shoulder so you dont overcut the flash hole. I ruined a batch of Lapua brass many moons ago. That was an expensive lesson.

http://www.kmshooting.com/catalog/flash-hole-uniformer-tools/flash-hole-uniformer_master-standard_0080.html

[ferrum]

I think I have it figured out now.
I picked up a flash hole uniformer and a COL gauge.

Flash Hole Uniformer:
The Winchester brass was pretty clean but the Hornady brass was very jagged around the flash hole.

COL Gauge:
When I measured my chamber I was surprised to see the measurement was 3.440" .2" beyond the recommended COL for the load. Even if I backed off of this measurement by a couple thousandths it would have left very little bullet left to seat in the brass. Is this common? I expected a few hundredths to the lands, not .2"

I decided to seat the bullet to 3.340" -- the Hornady manual max COL listed for the 30-06 -- and still .1" off the lands.

My best 4 shot group was .5" using a 168 grain Amax in front of 48 grains of Varget.
49 grains of varget would have been a good group (<3/4") but I forgot to take a fouling shot first first thing in the morning

I will now work up a few loads using hunting bullets, knowing that I need to seat them long.

[Zombie Steve]

700's are notorious for a huge amount of freebore. A big jump isn't anything to be concerned about. Load your OAL to function in the rifle's magazine and move on to other things...

I shoot the same load with an A-max - 48.1 grains of Varget loaded to 3.240", CCI large rifle primer, Winchester brass. Not a smoking load at just under 2,600 fps from my 22" barrel, but it is very accurate and consistent out to 500 yards.