still stumped with a 260

W

williev18

Guest
ok guys ive gotten very good advice here before, and i;m hoping it will work again. I have a savage model 16 rebarreled with an ER shaw 26 inch magnum coutour barrel. Its shambered in 260rem with a 1-8 twist. i've got it shooting very consistantly under 1/2 inch 5 shot groups at 100 yards. The problem lires when i move to 200 it opens up to 2 1/2 inches in almost a perfect horizontal line. A first i blamed bad mirrage and bad wind reading on my part, but tonight i had no wind or sun and still got 10 five shot groups all exactly 2 1/2 inches acrost, all in an almost perfectly horizontal line. Im using a 130gr berger VLD over 43gr H4350 doing 2860fps with a std deviation of less than 10fps. for some reason it seems to shoot the best with the bullet fully jammed into to lands, which seems odd for VLD's. I have pretty much ruled out bedding or optics because the other two barrels i have for this rifle exibit none of these traits. I purchased this barrel with thoughts of shooting out to 500-600 yards but if its going to lose MOA at 200 whats it going to do out further.

Thanks
Will
 
How do you know what the wind is doing? What do you have out there to show you? Also, when tuning their 6PPCs, some very good shooters have found that when their load is tuned to no vertical at all, that for some reason their bullets are more wind sensitive. For that reason Tony Boyer has said that he tunes for a half of a bullet of vertical at 100 yards, and twice that at 200. About the condition of the wind, I wish I had a dollar for every one that thinks that he can tell what the wind is doing between himself and the target, without some sort of flags. It is a common misconception, except among benchrest shooters.
 
I had 5 pin wheel flags set up all three test sessions. I shoot score on a monthly basis, this is just a hunting rifle i am playing with. Its complete loss of horizontal hold at 200, has me stumped. all of the numbers say it should be stabilizing the bullet ok. what has me worried is the fact that it will only group at 100 with the bullets set out to full jam into the rifling. in my experiences VLD bullets dont shoot well this way. I dont know if i have a problem with my chamber, or throat. I am using a lee collet neck die and bullet seating die, so the bullets should be straight. I would also think that a miss alighned bullet would affect verticle,unless i was unlucky enough to index the cartrige the way every time. i dont have a consrticity guage, my 30 br has never given reason to buy one, but thinking it my be time to get one now that im playing with long for caliber bullets.

the groups at 100 show no preferance to verticle or horizontal but a nice round group with all holes touching.
so i guess im still looking to find some on that has run into this b4.
 
I had a similar problem (only worse) and cured it by doing the Berger method of trying 5 different seating depths from touching, .030 jump ,.060 jump ,.090 jump and .120 jump.
I never would have believed that a gun could be so far out of tune as to throw shots horizontally almost clear off the 24 inch target when jammed and then when jumped stack them in an inch at 300 yards. I really thought the gun or scope was broken till somebody helped me out with this one by letting me shoot some factory loads that were loaded shorter than jam. May not be your problem but easy to find out.
 
Quite often I have seen the horz spread come as the result of the trigger and/or the bench set up, i.e. the front and rear rest set up.
 
OK just returned from the range, tried setting the bullet with progresivly more jump. got the same 2.25" horizontal spread with full jam, then set back in .020 increments. unfortunatly the spread grew .5 inch with each increment and started to get some verticle at .080 off the lands. i gave up at .120 off when the groups grew to over 5 inches. i gave the barrel plenty of time to cool between groups and cleaned every 3 groups with 2 fowling shots after cleaning. as far as bag set up im shooting off my same bags i use with my BR gun with a bag rider plate bolted to the stock up front to fit the 3 inch bag. Ive tried pushing the harder and slower, ive tried 120-140 gr bullets. the berger 130's are the only bullet ive gotten consitency out of. It will shoot under 1/2 inch at 100 prety easly making nice round groups but when i move to 200 its a 2-2.5 inch horizontal line every time. i havn't gotten a chance to shoot at 300 yet, is there any chance the bullet just hasnt gone to sleep yet. its an hour drive to shoot 300, and i dont know if its worth my time. at the way the groups are spreading its gonna be over 6 inches at 300. Should i have this barrel bore scoped or is it time to find another one and try again.

Thanks
Will
 
I'd have to say that if your load is shooting half MOA at 100 yards and double or triple that at 200 yards that the bullet has gone to sleep at 100 yards and there's another problem somewhere. Round groups going to horizontal by doubling the range and with wind taken into consideration is something I've never experienced.

Is the barrel in the same condition, clean or fouled, hot or cold for the groups at 100 and 200? The only thing I can think of is that there's either something going on in the barrel or that in trying harder to get inch groups at 200 yards you're doing something in guiding the rifle or squeezing the trigger that's contributing. Have you had another experienced shooter try the rifle at 200 yards? That might give a clue too.
 
I'm pretty sure its not my hold or trigger controll, its basicly the same action and trigger set up thats on my 30br and ive had this action for over 4 years with other barrels without this problem. Just to be sure,I had my father shoot the rifle last night also with same result. He doesnt do much with hand loading so had no load advise, but is very good with a rifle so it helped make sure it wasnt me. With both of us maiking identiclal groups id say its something in the set up. I did talk to one of the local gun shop owners today that sugested i have the bolt luggs lapped b4 throwing away the barrel. he thought the side ways force of having one lug load bearig more than the other could be throwing the shots horizontal. its never bothered with the other barrels i have for this action but who knows maby this one is more sensitive to such things.
 
100_2218.jpg100_2219.jpghere are a few of the targets from last night, after looking at themagain i do see a little verticle stringing in tthe 100 yard groups but how does that convet to horizontal at 200. i went to 3 shot groups last night to see if barrel heat was causing the groups to walk with the 5 shot, obvouly no help either.
 
I have been shooting the 6.5 -284 for a couple of years but my experience is limited to one barrel. My set up is a Savage Model 16 with a custom stock. Stock has a 3” wide block on the forearm. I shoot off a concrete table with BR premium quality front rest and sandbags. I am shooting a 29” 1-8 twist Kriger barrel. My better load is 140 Gr Berger VLD bullet just kissing the lands over H4831E with a CCI BR-2 Primer @ 2,900 fps. Groups are 0.25”

My faster load is 140 Gr Berger VLD bullet just kissing the lands over H1000E with a Rem 9.5 Primer @ 3,200 fps. Groups are 0.50”

With the H4831 Loads I found the groups to open up to 0.75” when I put the bullets 0.002 or .003 into the lands. When I moved the bullets out more about 0.010 off the lands the groups came back down to under 0.50. My experience is each barrel is different and the bullet position can vary with the Density Altitude, D.A. At our range in the early morning it is often about 75 degrees (D.A. @ 1,350). By noon it is 88 to 90 and D.A. is over 2,200. I usually keep the bullet position the same and back off on the powder 0.3 grs or so as the D.A. goes up to keep the barrel in tune. If D.A. changes 400 to 600 my barrel goes out of tune and the groups get bigger.

The torque in the 1-8 twist barrel is an issue. If your stock and table equipment are not right it will show up in your groups. I also shoot with levels on my rifle.

My other rule is never assume the scope is holding center. I have seen more bad scopes than barrels
 
Willie, your 200 yd groups are not showing much verticle, however the 100yd groups are. Doesn't translate to a good
load for me. Is your scope adjustable for paralax ?
 
As far a scope goes yes its adjustable for paralex, its a nikon monarch 6-18 with side focus. the scope has held zero for me for years, and i put it on the BR rifle a few weeks back to make sure it was holding zero, all is ok there. Octopus after reading your post the rotational torque comment got me thinking and i got to investigating my bech set up. i ended up finding that the top of my post on my sinclair top wasnt cut perfectly square but was high in the center causing the whole top to rock just the slightest bit. I never had considered the rest to be a problem because non of my rifles had given me a problem b4 off it. But the long bullet fast twist game is new to me. the other rifles i typicaly shoot off this rest are my 30 br with a 1-17 twist, and this rifle with a 308 barrel in 1-10 twist, and a 223AI with a 1-14 twist, obvoulsy none of these have the tourqe a 1-8 twist 260 will produce. A little time with a flat file and some JB weld seem to have made the rocking dissapear. We have the VT ibs meter states at our range this weekend so the 200 will be closed, and i will be biusy with shooting and helping run the shoot but i will let you know if you hit the nail on the head once i get a chance to test.

Thanks
Will
 
I would be suspect of the scope still. Over the years I have seen issues with the NiKon scopes, and many others, holding zero. I have a Burris 8-32X50 that was not holding Point of Aim. I checked it with a Hood Scope Checker. (The checker allows me to mount two scopes side by side on the rifle.) Using the checker I saw that the Black Diamond scope was not holding POI. Sent the scope back to Burris. Two months later it comes back with a note that nothing was wrong with the scope. I have had this same experience with Burris in the past. Some scope makers do not understand the need to hold precise POI. Nor do they seem to have a way to measure POI drift. I suspect the standard for POI drift is different between companies.

I had the same POI drift problem with Leupold Scopes several times As time goes on the scopes start to allow the POI to drift. Send them back to Leupold and they come back rebuild working right in less than a month.

With Nikon and Bushnell they send me new replacement scopes. So far the only scope I have never had to send back for repairs is the NightForce.

My conclusion is all scopes will drift POI. The questions are when and how much? Over time POI dirft becomes a problem. The solution for some shooters has been to lock the cross hairs. The solution for others is the high dollar scopes.

For me the solution is to understand that all scopes are subject to POI drift. And, to stay with scope makers, like Leupold, who understand the problems and take care of them.

That your scope held zero on the BR rifle does not mean that it is holding zero on the 260.

Using the Hood Scope Checker I have several times seen a scope hold zero for a few shots and then move as much as an inch on the next shot. The Burris scope discussed above was on my 222 with a 1-14T barrel. Low Recoil. It held POI for a few shots and then would move 1/8 to 1/4 on recoil. After a few shots it would move as much as an inch. This is very hard to detect without a scope checkers. A few years ago I had a Burris Black Diamond that walked an oval over five shots that was 3 to 4 inches to the left and about an inch vertical. It would repeat this track. This was on a 25-06 1-10 twist 15# rifle. I sent it back to Burris and they said it was OK. Sent it back a second time and they fixed it. Process took five months.

Scopes move POI. If you suspect you have a bad scope check it with a scope checker or put a scope that is known to be good on the rifle and check the rifle. Even the scope makers seem to have problems with this issue.

I have never figured out just why scopes start drifting POI but like most other BR shooters I know it happens often. Most shooters never have the problem because their rifles do not shot precise enough to show the problem. Target shooters see the problem often.
 
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note taken i will be sure to take another nikon i have along on the next test session to be sure.

Thanks
Will
 
Any update? If I were a gambling man, I would say this is your scope. Once a bullet "goes to sleep" it should stay that way well into transonic velocities which in a 260 should be at least 1100 meters with nearly any decent pointed bullet. Your scope may very well have some serious parallax. Make sure of the 200 yd setup to insure you have removed all the parallax. Any easier solution is to just replace this scope with one that is known to be good- borrow one if you have to.

Do you have a way to shoot 500 yards or more to see if it is a mid-range scope issue?
 
unfortunatly the furthest i can shoot at my home range is 200. im trying to get onto anther local range to try 300 but its a more private club. i havnt gotten to try it with another scope yet, but saturday im hoping to get some range time. im probably going to put on another nikon monarch i have thats homeless right now and has never given me any problems. i may even take the weaver t36 off my br gun to take with just to double check the load. i was hoping to be able to develop the load with the scope i was gonna hunt with but if its shifting POA i guess it might be time for a scope swap any way. if i remember right this was a nikon refurb, not sure what the warranty is. With the scores i got this week end i got with my BR gun im thinking my improvements i made to my bench set up where minimal, but who knows conditions this week end where rotten and im no conditions shooter. hoping for early morning calm this week end to make some ground on this problem. i will post an update this week end.
 
Maybe I don't understand your part of the country, but can't you just go to the nat forest somewhere and set up a target and shoot prone at any distance you want? I realize you won't have a bench, but if you put your rest on the ground, you should still be able to shoot good enough to diagnose this problem further.
 
Couldn't get mine close to performing until I got to 44.5grns of H4350. The load is between 44.5 and 45.0 grns. I am concentrating on seating depths now. Have not chronographed the load yet. But suspect its around 3000 fps with the Berger 130's. Have always had better luck jamming VLD's and jumping target boat tails.
 
I wish it was that easy but the only places that are unforested enough to be able to shoot that far are either too near residential housing, or are used alot for public resreation. I dont realy want to take out a ATV rider coming over the next ridge. I do have a place way out on a privatly owned section of power line that i can shoot between 600 and 1000 but its over an hour ride by atv and the Deer flies are realy thick out there right now.
 
unfortunatly when i get up around 44gr H4350 i start to see the primer dimpled and the bolt is sticky. at 43.5gr im getting just under 2900fps so i thing its where im gonna stop with this rifle. So far im with you on the seating depth at jam. till you seat them at jam with this rifle groups are all over the place. the only bullet ive found that likes any jump is the seirra mk 120's, but im looking for a little bigger bullet for better wind bucking, and seirra dosnt reccomend hunting with thier bullets. seeing as how thats what this rifles priamry funtion will be i figure no since tuning with a target only bullet. The more i think about it i think that it could be a scope problem at 200, but only time and testing will tell. In a way i hope its not because i love this scope for hunting. its light gathering is awesome, and the BDC recticle is very handy in conjuntion with a good range finder. But in another way it would be nice if its that simple, a scope is far easier to change, than fighting a hard to tune barrel.
 
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