patterns in my groups, what does it mean?
I posted a question in a thread "shoots worse after bedding" and after some dremel work the groups went back down. After some more shooting and load testing with 3 and 4 shot groups I've seen a pattern see pic. I adjusted my windage after the two "fowler" shots then shot the groups. http://i924.photobucket.com/albums/a...7/DSC_7292.jpg
I've been trying different bullets, powders, bipod vs sandbags and shooting styles of hard hold to more free recoiling. I will explain my rifle. Stevens 200 long action, 25-06 AI, shillen stainless select varmint contour, rifle basix trigger, recoil lug from northlander, BVSS take of stock, bedded. I do not have any type of cheek rest, which I suspect could be part of the problem. I have used the scope and rings (Vortex Viper 6.5-20) on two other rifles without getting this pattern. I have checked the action screws several times and they are tight, but I have not used a torque wrench. I don't shoot more that 5 shots in a row and do not let the barrel get too warm.
I've been shooting 85 gr nbts and 90 gr barnes solids with H4350, RL17, H4831SC, and H1000. I'm using data from a Sierra manual, which I think is pretty conservative, and I have had no signs of pressure. I'm using winchester brass, nect turned and redding dies...Type S bushing fl sizing dies and Type D seating die.
I have what I consider a solid bench made from some heavy tubing with two layers of 1/2 plywood which is anchored into concrete with 1/2" concrete anchor bolts. I have tried shooting off a bipod with rear sand bag and sand bags front and rear. Before shooting I slide the rifle slightly in the bags to see if it will recoil straight. I've been paying a lot of attention to my shooting form and have not figured out what my errors could be.
Re: patterns in my groups, what does it mean?
...Looks like it needs more powder to me...Whatever you're useing..
Re: patterns in my groups, what does it mean?
My money is on a bedding problem. 3 B's of accuracy, barrels, bullets and bedding. You got two covered.
Re: patterns in my groups, what does it mean?
2 shot groups...and plants two side by side? Weird.
The FIRST thing I would do, let somebody else shoot the rifle. No kidding. If the groups improve, you have your answer. If not...
Take some cardboard with you...the thickness of a matchbook cover and shim between the forend and the barrel...egqually on both sides of the barrel. Any improvement? If not.........
Try a different scope.
Re: patterns in my groups, what does it mean?
I shoot a 28" Shilen 25-06 and I had so much trouble with the same thing sometimes it would shoot pretty good but most of the time it would put two on top of each other and throw one out. I was pulling my hair out over this, I was working with 90gr blitzkings, 100 matchkings and 100 B-tips and then I got hold of some Berger 115's and loaded some up for a ladder test with H-4831 and WoW now it almost always prints nice clover leaf groups sometimes it dang near one holes.
Re: patterns in my groups, what does it mean?
I am considering geting some Bergers, it does seem to like the longer bullets. I'm going to shoot more today, will use the Chrony, and try some different charge weights. I will check again if everything is tight that is supposed to be tight, and free floating what should float. My wife offered to shoot the gun, but I don't know if my pride could take it if she shoots one hole groups.
Re: patterns in my groups, what does it mean?
obviously that barrel just aint gonna shoot. So you need to get rid of it ::)
Re: patterns in my groups, what does it mean?
Quote:
Originally Posted by coonhunter70
I shoot a 28" Shilen 25-06 and I had so much trouble with the same thing sometimes it would shoot pretty good but most of the time it would put two on top of each other and throw one out. I was pulling my hair out over this, I was working with 90gr blitzkings, 100 matchkings and 100 B-tips and then I got hold of some Berger 115's and loaded some up for a ladder test with H-4831 and WoW now it almost always prints nice clover leaf groups sometimes it dang near one holes.
Goose, I guess what I meant to say was that your barrel may like the heavier bullets as mine apparently does.
Re: patterns in my groups, what does it mean?
Does your barrel fowl? Have you tried a new scope? Have you tried SMK's or SGK's. Does your twist match your bullet weight?
Re: patterns in my groups, what does it mean?
Double grouping may be a sign of a parallax problem or something loose in the scope. Try a known good scope.
Re: patterns in my groups, what does it mean?
Did you ever get this resolved, or do you need to try a different choke :P :P
Re: patterns in my groups, what does it mean?
I went over to a neighbors house that has way a machining business and shoots some competitions. We removed the scope and checked the rings for alignment, checked out ok. We removed the action from the stock and after some inspection he saw the contact area for the rear of the action was just a thin line on the clip that holds the magazine in the stock. That line had been there since it's initial inception as a stevens 270, but we decided to remove the "L shaped" bracket and bed that part of the action. Since then I have fired 2 groups, much better. I actually fired the best group of my life, putting 3 shots into a hole that measured right at half inch outside edge to outside edge.........the only problem was I decided to shoot 5 and lost my edge bringing it out to about an inch. In that sense, the jury is out to see if I can get consistent 5 shots in a decent group. He has a good bench set up and I plan to go back when things settle down from the holidays.
