Getting a featherweight barreled rifle to shoot????

[msinc]

#1/Check out this on YouTube- Cooper Firearms Raptor.....it shows the factory test firing of a Cooper .308.....I can't tell what barrel contour, but they apparently see rapid fire as not an issue with accuracy.
#2/ Even though the scope has parallax adjustment....did you verify none was present.....the P/A markings on scopes are notorious for not being accurate.
#3/ What do the bullet holes look like....nice round holes that appear smaller than the caliber....or elongated? Have you checked the twist rate stability table on Bergers website that the bullets are in-fact OK for your twist rate?
#4/ You have three 5/8" groups out of 9, I don't think it's the load, either your cheeking harder on some, pulling the trigger inconsistent (pulling on edge and not center) or don't have parallax all out. Slow moving mirage will move you some of that 1-1/8" as will a missed light breeze -especially a reversal. You need flagging to eliminate these possibilities.

I have no doubt that one shot after another is probably not detrimental to accuracy, but it cannot be too terribly good for the throat. She heats up pretty quick, but with less mass she also cools quicker too.

I did in fact look for parallax and you are right, I was shooting on a measured 100 yard range {I know this because I own it} yet the focus knob read a little less than 100 when it was set right.

Bullet holes appear to be perfect small round nice punch outs with no evidence of yaw or destabilzation of the bullets.

I am definitely not above some sort of flinch or other shooter induced error, but the same shift every time??? I guess it is possible to be consistently inconsistent. I'd like for it to be this...then I'd know the rifle and scope was okay!!!!

FWIW, one thing I have noticed...the barrel has gone from having to be soaked overnight in Shooters Choice to several strokes of a brush and wiping clean with a patch. I intend to shoot it some more tomorrow, will have a range report soon after. Thanks again for all the info fellas!!!!

 

[LHSmith]

I have no doubt that one shot after another is probably not detrimental to accuracy, but it cannot be too terribly good for the throat.

It's a hunting rifle, how much is it really going to get fired in a season? Besides we're talking 3 shots. The type of powder used will have more detrimental effect on the throat than a few rapid fire shots.

 

[Dusty Stevens]

I have to confess Mr. Stevens...the thought of selling it has crossed my mind a time or two, the thought of making someone happy would be great, especially you...but that $500.00 thing, I am having a hard time wrapping my head around that part!!!!!!

If you decide to ditch it id like a shot at it. I need it for my collection i dont have one of those

 

[grovey]

There has been a Montana thread or two on 24HR Campfire. I remember they gave tuning tips to make those rifles shoot better. Their were several, but the only one I recall was the mag box being to tall and binding up the action.

 

[WEL]

I spent quite some time trying to get a Kimber 7wsm to shoot. Since this is a lightweight hunting rifle I chose to fire the first shot from a cold bore, then 2 follow up shots as quickly as I could accurately regain a sight picture. This is what the rifle will see in an actual hunting situation. With the right load it would put the first 2 shots almost touching but the third shot would open the group to 1" or slightly more. Once I found the right load I would take it out on different days and conditions and verify that poi for those first 2 shots was not changing over different conditions. When you fired those multiple groups how long did you wait between each shot grouping? When testing mine I would wait for the rifle to cool completely before attempting another shot grouping or it would shoot like crap. Kimbers can be very finicky and some just won't shoot moa no matter what you do.

 

[Changeling]

For those who thinks thin barrels and rapid fire is not an issue with PRECISION (not accuracy, these two terms are not interchangeable), here is a real world example of an “awkward moment” for Germany arm forces when they found out that their main battle rifle – the H&K G36 which has a “pencil barrel” “doesn’t shoot straight” when it gets hot…

http://bearingarms.com/awkward-moment-hk-fanboys-find-germans-call-g36-rifle-doesnt-shoot-straight/

How those idiots got themselves into that jam I have no idea....

WOW! Minute of Man accuracy at 200 meters!!! H&K trying to talk their way out of it by saying they didn't think a "Military" arm needed long strings of fire. I think H&K is going to get a spanking in Germany

OP, sorry for the interruption to your post, I was just really shocked by the above!

 

[6xcshooter]

i have a cooper in a 280 ai. try IMR 4831 with berger 140 gr. vld hunting bullets , works for me 1/2 inch groups @100yds

 

[msinc]

Today's range test was with IMR4831 and a Nosler Ballistic Tip. This combo shows the most promise. I also noted that the very first shot from yesterday and the very first shot from today if superimposed would be in the same hole. I got some more 5/8" groups and a 3/4". I tested loads at half grain increments and the start load was the best, the highest load which was 2 grains higher opened up and was the worse.
When I got home I might have discovered something...I decided to concentrate on this bullet and powder for a final load work up, so I set out to strip the other rounds I have loaded. I try not to miss an opportunity to Q.C. my own work. So, I set up to check all the charge weights and while that proved to be okay I did notice that some bullets were very hard to pull while others took no where near the same effort to extract. This was all new brass that was outside neck turned and annealed. I was very surprised to see this because the seating effort felt good. I seat with a L.E. Wilson straight seater and although I did use my arbor press to make sure I am bottoming the bullets all the same I could have pushed them in by hand.
Isn't it feasible that the ones with higher neck tension could create more pressure and shoot different??? Could this be what I have been chasing all along??? What causes this and how do I stop this inconsistency???

 

[jlow]

A few questions.

One is were all the rounds loaded at the same time and have been sitting around for the same period, and how long?

The other question is how do you size your neck and to what neck tension?

Yes, definitely - inconsistent neck tension does indeed cause inconsistent precision.

 

[L.Sherm]

The neck tension you are describing will cause fliers, how are you annealing your brass?

 

[AckleymanII]

Nothing in my shooting career has caused ulcers like a fly weight barrel. IN three different rifles, the addition of a muzzle break cured all ills in spades.

Same thing applies to a model 7, put on a muzzle break.

Otherwise, consider two, cold bore shots... very different concept for group shooters.

For me, Boyd is dead nuts, give the gun a very good grip, pull into the shoulder, solid cheek weld.

 

[msinc]

A few questions.

One is were all the rounds loaded at the same time and have been sitting around for the same period, and how long?

The other question is how do you size your neck and to what neck tension?

Yes, definitely - inconsistent neck tension does indeed cause inconsistent precision.

All rounds were not loaded the same hour, but they were loaded within 24 hours of each other. They did not sit for more than two weeks.
I am sizing with an RCBS full length size die. I have tried full length sizing to dead on headspace and I have tried 3/4 sizing of the neck with the same die. I outside neck turned the cases just to knock off any high spots, anneal them and size. The bullets when seated seemed like they pushed in easily. As said before, I could have seated them with the palm of my hand. All brass was new, once fired to fireform. The brass was both Hornady and Remington.
Is there some sort of lube that can be applied so the necks cannot lock to the bullet??? Never had to do this, but then again, never had a rifle this picky either. Would the shooting world stop turning if I applied a little sizing was to the bullet and neck just to test a few rounds??? I get that graphite is supposed to be better if they are going to be stored. What about mica, like for shotgun reloading???

 

[msinc]

The neck tension you are describing will cause fliers, how are you annealing your brass?

The same way I have successfully done for all my rifles it since 1991. No reason for it to stop working now, not doing anything different.

 

[LHSmith]

Today's range test was with IMR4831 and a Nosler Ballistic Tip. This combo shows the most promise. I also noted that the very first shot from yesterday and the very first shot from today if superimposed would be in the same hole. I got some more 5/8" groups and a 3/4". I tested loads at half grain increments and the start load was the best, the highest load which was 2 grains higher opened up and was the worse.
When I got home I might have discovered something...I decided to concentrate on this bullet and powder for a final load work up, so I set out to strip the other rounds I have loaded. I try not to miss an opportunity to Q.C. my own work. So, I set up to check all the charge weights and while that proved to be okay I did notice that some bullets were very hard to pull while others took no where near the same effort to extract. This was all new brass that was outside neck turned and annealed. I was very surprised to see this because the seating effort felt good. I seat with a L.E. Wilson straight seater and although I did use my arbor press to make sure I am bottoming the bullets all the same I could have pushed them in by hand.
Isn't it feasible that the ones with higher neck tension could create more pressure and shoot different??? Could this be what I have been chasing all along??? What causes this and how do I stop this inconsistency???

Are you saying that you annealed new brass?
Causes- inconsistent anneal, case necks interiors that are clean to their original state, insufficient neck chamfer, bullet-to-neck weld (takes a length period of time).
Solutions- mop the case neck in graphite or VERY light coating of case lube.
Try to duplicate your last performance if you repeat you are GTG. Overlaying the first shots of each outing was good. Also mark the bullets with colored markers to ID 1st,2nd, & 3rd shot. If 3rd shot is usually the outlyer then that is to be expected and it is what it is.
FWIW, IME the heavier the gun the more accurate it is with stiff powder charge i.e. my HV BR guns always like max. loads while my LV guns shoot best with lighter charges ( same cartridge, same type powder, same bullet).
In other words, don't push the issue if your gun only likes starting loads.

 

[msinc]

Are you saying that you annealed new brass?
Causes- inconsistent anneal, case necks interiors that are clean to their original state, insufficient neck chamfer, bullet-to-neck weld (takes a length period of time).
Solutions- mop the case neck in graphite or VERY light coating of case lube.
Try to duplicate your last performance if you repeat you are GTG. Overlaying the first shots of each outing was good. Also mark the bullets with colored markers to ID 1st,2nd, & 3rd shot. If 3rd shot is usually the outlyer then that is to be expected and it is what it is.
FWIW, IME the heavier the gun the more accurate it is with stiff powder charge i.e. my HV BR guns always like max. loads while my LV guns shoot best with lighter charges ( same cartridge, same type powder, same bullet).
In other words, don't push the issue if your gun only likes starting loads.

Yes, the brass, while never fired was not off the shelf recent manufacture. I didn't know how old it was so I annealed it. The expander ball didn't chirp when I sized it, but the brass seemed a little stiff.

"case necks interiors that are clean to their original state"....you mean like wire brushed clean to bare brass or sts tumbled??? No, all of the test cases have been fired at least once before testing. Some twice, but they have been kept separate. Not seeing a difference on paper anyway...but kept separate just the same.

My experience with heavy barrels and hot loads is the same...light guns/lighter loads always proved better accuracy. In this case the "lighter" start load was still fairly stiff.
I am real happy with the "first shot" being in the same hole...that is really what I need at the end of the day. Nice to confirm how accurate a rifle will group, but I am not going to be measuring group size on the shoulder of a black bear!!!

Getting ready to load some more test rounds...range report to follow.

 

[LHSmith]

"case necks interiors that are clean to their original state"....you mean like wire brushed clean to bare brass or sts tumbled???

Either wire brushed or sts clean....in other words lack of carbon coated.

 

[LHSmith]

Getting ready to load some more test rounds...range report to follow.

Let us know more details....like rate of fire?, is there a pattern which round impacts where (last shot outermost)?, still factory bedded?, did you change action screw torque?

 

[Dusty Stevens]

Not annealing brass right doesnt cause groups that big- come on. People didnt just start shooting sub 5" groups because annealing came along. Br shooters never anneal and shoot sub 1/4" 5 shot groups

 

[L.Sherm]

You are not mixing your hornady and remington brass, correct

 

[L.Sherm]

Dusty his last test session was 5/8and 3/4 groups with the neck tension he was describing will make those type of groups!