260 remington. went bad.

I have a 260 remington with a criterion light varmint barrel/ 1-8 twist.This barrel replaced a factory barrel. Gun has a accustock and accutriger. Had this thing shooting extremely well. Groups all of a sudden really opened up. Did nothing to the gun. Probally had about 350 rounds thru it when this happened. Cleaned it more than once and can't seem to find a load that it will shoot nearly as good as before. Was shooting 0.350 groups at 100 yards with accubond 130 and 140 grain bullets. Having a hard time finding the inch mark right now. Ideas???

Seating depth, runout, change in brass? Or primers? New lot of powder? If nothing has changed then maybe you weren't in the middle of a node but on the edge of one. Weather changes can affect that. Just some ideas.

A little more info would be a good thing but im gonna go with the things to start with....check action, base and scope ring screws if all good id do a tracking check on the scope if that turns out ok pull the barrel and action out of the stock and check the contact points of the action and lug for damage.

Have you tried a good copper solvent? Try using gun slik foaming bore cleaner and get all the copper out.

Scope rings or base loosened?

Are you reloading? If so, do you have a temp insensitive powder? Hot weather to cold weather could be a huge deal in accuracy of a load.

Have done all the above. Was using IMR 4064 powder. Used gun slick. Also Butchs Bore Shine. Brass was new and all the same Lapua. Always trim and debur in big lots, have 200 rounds. Powder is out of a 8 lber. Primers all out of the same 1000 lot box. Rings are tight. Scope is a Nikon pro staff 4x12. Have not checked the base. Put that on and use blue lock tight like on all my other rifles. Have a bunch of different bullets/powder combos loaded up last night, now need the wind to slow down.

Someone please find a solution, I have the same problem!

Find a Smith with a bore scope, but it is full of carbon

There is something you have missed here, what it is I have really no idea. One thing I know is, after doing a really good cleaning, the barrel needs to once again be fouled. Also, if a carbon ring has formed somewhere in the barrel, it needs special attention. Another thing may be damage to the crown?

If any of the above recommendations don't solve the problem, free to shoot us an email at contact@criterionbarrels.com. We'd be more than happy to help troubleshoot the problem and get that rifle back to performing like it was.

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Originally Posted by CriterionBarrels

If any of the above recommendations don't solve the problem, free to shoot us an email at contact@criterionbarrels.com. We'd be more than happy to help troubleshoot the problem and get that rifle back to performing like it was.

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Well this right here is excellent! If it was me I'd have it in the mail today. Way to go CRITERION!

IF and I say If there is a carbon ring, what's the correct way to get rid of it. And I do know it takes a few shots to refoul a clean barrel

Jim (Apache Gun WOrks) recommended I use Wipe Out foaming bore cleaner. It did the trick for me. I used it maybe 4-5 x over the course of several days. Not sure if that was necessary, but it worked great.

Other than trimming length, what else have you done to maintain the brass? Are you checking the headspace to set FL sizing, neck sizing, annealing, etc?

I'd say that the root of the problem is probably the scope. Sounds like it's dying. Try a known-to-be-good, preferably higher quality scope, to rule out this possibility. Not trying to put down your equipment at all, but it happens, even with higher quality scopes.

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Originally Posted by tom338

IF and I say If there is a carbon ring, what's the correct way to get rid of it. And I do know it takes a few shots to refoul a clean barrel

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from what youve said its your scope as you have ruled out all other problems for the most part and i REALLY doubt its carbon with only 350 rounds through the barrel...like i said do a tracking check on the scope...set up 2 targets at 100(200 would be better) and shoot for center on a 3'tall by 2' wide piece of paper with 1 black dot dead center when your on or close switch to the clean target and dial up 5moa and aim at the dot then down 5moa aiming at the dot then back to zero then repeat the above but going left then right with scope on 0...i bet you find your scope not tracking true.

My first thought is it's your stock, bedding or torque. I have to admit I know nothing about the accu stocks. My second quess would be the scope. Have you changed the way you seat bullets possibly introducing runout? Is your scales repeatable?
I guess this is part of the fun of shooting and reloading is learning how to chase down the problems when accuracy goes south. Hope you figure it out and share the fix with us. Good luck.

When you shot your good groups what was the temp outside? What was the temp outside when you shoot the terrible groups? IMR 4064 is somewhat temperature sensitive, if the temp changed a bit, you may have shifted out of the Optimal Charge weight for that combo.

I am not an expert loader by any means. Self taught. I talked to several guys who belong to a local club about this barrel. One asked about annealing. I have not annealed the cases. But with only about 4 rounds thru each case two of the guys agreed I should not have to do that yet. I put this barrel on myself and checked headspace with a go, no go, and a field gauge by foster. I am FL sizing and the die is set correct. I am not new to reloading, been doing it for 30 years, but still have lots to learn and want to know. If there is a carbon ring can you feel it when you run a patch thru?? Temps when I first shot were in the 60's-70. Now in the 30's. I did shoot today and may have found another load. Very frustrating. I shoot 4064 in 5 other rifles and never a issue until this year. Now my 338 win mag won't shoot it. Switched that over to H4350.

Look to your scope as others said. 4064 is like most other powders and can exhibit sensitivity to temp change. Federal still uses a similar powder in the FGMM stuff for .308. Velocity difference can be as much as 1 fps per 1 degree. So that could be a 30-40fps shift. If your on the edge of a node that could easily push you out. You mentioned you had h4350. That is by far the most popular powder for the .260 with bullets over 120 gr. maybe a powder switch is in your future. Hope you find the issue.

Ok im going to be the bad guy here and tell you.....it is either your scope or you!!!....a 30 to 40fps spread WILL NOT cause the problems your having....a carbon ring(which ive never heard of)is NOT going to cause the problem.....CHECK YOUR SCOPE LIKE I TOLD YOU!!!!!! If you scope is tracking true then the problem is you!!

Am going to check the scope out. I don't think its me. I have the same scope on a 338. So while the barrel is cooling off on the 260 I am shooting the 338. shooting way better groups with the 338 than the 260. Off to the deer stand this morning. Then hopefully have this issue resolved before my trip out west. Thanks for all the advice will post on what happens to the 260.

I'll second what longrange said.

When you are certain and for sure there is nothing wrong with the the rifle always check the scope. Swap it with a spare if you have one or run a box test.

After the scope is confirmed as good the last possibility is the shooter and his technique. How stable and consistent is the position? Breathing and trigger control? Follow through? Flinching? Eye relief? Grip?

Try a different scope. That one is entry level and may have gone 'west'.

First check the crown and make sure there is no damage.if that is ok then some bore polishing compound in the barrel.

You use Iosso bore paste or JB Bore taste. You use a brush one size bigger and saturate the brush and turn it around and around like 20 times and then clean it out(the paste) All paste turns black when used, you are looking for a dark brown color. If you knew someone with a bore scope it would tell you immediately if the hard carbon ring in the neck area of the chamber is there. Carbon rings are always an accuracy killer.

For hard carbon deposits, Wipe-out Carb-out works well, as does GM(as in General Motors') Top Engine Cleaner, if you can find it. But I don't think this is necessarily your problem. Can't hurt to do it, though.

Did you get to try swapping scopes yet?

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Originally Posted by barrel-nut

For hard carbon deposits, Wipe-out Carb-out works well, as does GM(as in General Motors') Top Engine Cleaner, if you can find it. But I don't think this is necessarily your problem. Can't hurt to do it, though.

Did you get to try swapping scopes yet?

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man i loved the GM TEC 2 patches 5mins and one more patch and carbon gone!! im using slip 2000 carbon killer now and its pretty good stuff.

Well it's NOT the scope, and it's not me. For some reason this barrel just won't shoot the loads it started out shooting so good. It does however like some different loads that it did not shoot well at all before. Now if it will just repeat the load again. Will find out when the wind goes down again. Did not clean the barrel from the last 40 test rounds thru. And put another 60 test rounds thru when I found another bullet to group good. Still no clue as to why the groups fell apart and won't group from the first found bullets, does not make any sense

I thought for sure it was the scope. My factory 300wm barrel was like this...id work up a good load and the next time id shoot it wasnt so good. As long as the barrel was clean it shot well after about 50 rounds it would start to drop off and 75 to 100 rounds nothing would shoot...I got tired of that real quick and rebarreled it.

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Originally Posted by tom338

Well it's NOT the scope, and it's not me. For some reason this barrel just won't shoot the loads it started out shooting so good. It does however like some different loads that it did not shoot well at all before. Now if it will just repeat the load again. Will find out when the wind goes down again. Did not clean the barrel from the last 40 test rounds thru. And put another 60 test rounds thru when I found another bullet to group good. Still no clue as to why the groups fell apart and won't group from the first found bullets, does not make any sense

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Temp / weather swings?

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Originally Posted by CriterionBarrels

If any of the above recommendations don't solve the problem, free to shoot us an email at contact@criterionbarrels.com. We'd be more than happy to help troubleshoot the problem and get that rifle back to performing like it was.

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Soooooo! I think this is the answer. Or you could just keep @#$%^&* around with it!

I have been in contact with them. They wanted info and I sent it to them today. Sooooooo…while @#$%^&* around with it, I found a load it will shoot so I can take it on a hunt next week. If it repeats what it shot the other day which was a 0.30 3 shot group at 100 yards. Maybe with a little tweaking that group will shrink.

tom338
did you use the same powder?
did you need to increase or decrease charge?
did you use the same bullet?

IMR 4064 out of the same jug. This barrel just likes it better than anything else I have tried in it, h4381sc, h380,w760, h4350,h4320,rl19,rl17,rl22.
Before groups fell apart this barrel shot 130 and 140 grain Nosler accubonds. Both would shoot 0.350 groups. The 130 liked 37.0 grains and the 140's 36.0 grains of 4064. When the groups opened up I tried more and less powder, different seating depths--lots of things, different primers. No good. Now the barrel likes ( am going to try again today) 120 grain Barnes TTSX over 37.5 grains of 4064. Seated 0.40 off. Tried 0.50 off and 0.60 off, 40 was the best with 0.30 group at 100 yards. Before this barrel would not group Barnes any better than 0.925. I kept track of all the different things I tried. Barrel also hates BR primers, or at least the CCI's. Likes WLR primers best.

Now that's interesting!
I would assume something changed in the manufacturing process of the bullets, but I'm just guessing.
I will have to save this for future reverence!

You say you're getting .3" groups, with the old loads and the new, which is excellent performance by most any standards. Just out of curiosity, on the groups that "fell apart", to what extent are we talking? .5? 1"? 1 1/2"? That's just strange.
Eta: I mean you were getting .3" groups with the old loads.

When I say the groups fell apart they went from 0.350 at 100 yards to 1.25. That was using 130 grain accubond bullets and 37.0 grains of 4064. Thats what it does right now. Can't even get a 1 inch group any more.

Now with Barnes 120grain TTSX am shooting 0.300 @ 100 yards. Did it again today. That load this summer and up until a week ago would shoot 0.850 at best. With the Noslers shooting so much better I never tried to tweak the Barnes until now.

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Originally Posted by tom338

When I say the groups fell apart they went from 0.350 at 100 yards to 1.25. That was using 130 grain accubond bullets and 37.0 grains of 4064. Thats what it does right now. Can't even get a 1 inch group any more.

Now with Barnes 120grain TTSX am shooting 0.300 @ 100 yards.

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A few weeks ago I decided my 260 was going to be my backup goat scare'n gun. Ran to the local clip joint and picked up a box of 120 NBTs, what I used the last time two years ago. Loaded some teeth, to the range ....1-1/2" - 2" shotgun patterns. Hummmm...re-read my scribbling (notes) then tried an old load, 120 Nosler Solid Base, H4350....1/2"-5/8". More Hummmm The NBTs shot a tad better two years ago so sump'm changed.

Pulled the box of NBTs, about half measured .570" ogive to heel, the rest anywhere from .582"-.586". To make matters worse, I used a split neck case to soft seat both, the seating depths of the .570"s were within .001" every time, the rest were all over the map. I sorted then loaded 10 of the .570"s, 1/2" groups. So now I have maybe 15-20 good bullets and about the same number fishing sinkers.

Don't ever believe they don't mix bullets made on different machines-dies!.

Bill

Could not stand it anymore….sent the barrel back to the company. Will see if they find anything out or not.

Out of curiosity, were the bullets that aren't grouping now from the same box/lot # as the bullets you tested?

Had the same problem on a 30-06. I swapped out the barrel, redeveloped a load and now it shoots sub MOA at 200 yards.

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Originally Posted by BillPa

A few weeks ago I decided my 260 was going to be my backup goat scare'n gun. Ran to the local clip joint and picked up a box of 120 NBTs, what I used the last time two years ago. Loaded some teeth, to the range ....1-1/2" - 2" shotgun patterns. Hummmm...re-read my scribbling (notes) then tried an old load, 120 Nosler Solid Base, H4350....1/2"-5/8". More Hummmm The NBTs shot a tad better two years ago so sump'm changed.

Pulled the box of NBTs, about half measured .570" ogive to heel, the rest anywhere from .582"-.586". To make matters worse, I used a split neck case to soft seat both, the seating depths of the .570"s were within .001" every time, the rest were all over the map. I sorted then loaded 10 of the .570"s, 1/2" groups. So now I have maybe 15-20 good bullets and about the same number fishing sinkers.

Don't ever believe they don't mix bullets made on different machines-dies!.

Bill

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Good to know, I'll have to measure my SMK's and A-Max's I'm using in my 6mm BR. I recently reinstalled that barrel on an action and bedded it in a BVSS stock and accuracy is nothing like it was on the old action/stock set up.

This has been an enlightening read. Sorry to hear of the troubles you fellows are having.

Same box of 130 and 140 and 120 grain bullets. Then a bunch of different bullets and could not find anything that would work. They are working on it now. They have been e mailing me with updates, very good customer support so far.

I have heard several reports of barrels gaining speed as the have been broken in. This may or may not be the case, but I do have a .308 barrel that shot really good first 100 rounds then it opened up, I played around for 200-250 more rounds trying to develope a new load,,, then I found a good one and it has held .3" groups up to now 1500 rounds and counting. Barrels are like women, you don't know what there really like until you marry them.

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Originally Posted by DanSavage

I have heard several reports of barrels gaining speed as the have been broken in. This may or may not be the case, but I do have a .308 barrel that shot really good first 100 rounds then it opened up, I played around for 200-250 more rounds trying to develope a new load,,, then I found a good one and it has held .3" groups up to now 1500 rounds and counting. Barrels are like women, you don't know what there really like until you marry them.

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LMAO ain't that the truth!!