Savage 12FV 223 used to shoot great and now sprays bullets

[jfw432]

I bought this rifle about a year ago and have loved it. I've bedded the stock, stiffened it with epoxy and fiberglass fibers, and weighted the back end. I've also lightened the trigger down to about 14 oz and put an Athlon Midas BTR 4.5-27x scope on it.

With the exception of the first 50 or rounds, it's only ever had my handloads run through it. I went through the whole process of developing my loads with ladder tests out to 400 yards, COL grouping tests, etc. Generally 1/2-3/4 MOA were standard if I did my part but realistically the worst I ever got was around 1 MOA before any kind of load development was done. Lately however, the best I can get is like 2-3 MOA using the same bullets and handloads. My rounds do shoot around 3300 fps and I shot around 1500 rounds through it before the accuracy went to crap and the last 500 shot over 6 days have been total garbage.

Things I've checked and determined to not be the cause:
Swapped on a friends scope to rule out any scope issues
Checked torque on the rings and bases
Ran the same brand cases after being freshly prepped
Tried Sweets 7.62 copper fouling remover
Checked the torque values on the bolts holding the action to the stock
Checked to make sure the bedding and stock hadn't cracked
Checked to make sure the barrel is still free floating
Weighed all powder charges to within 0.05 gr of each other
Shot my rounds out of my friends gun and they grouped well

I'm at a loss as to why my accuracy went to absolute crap. Surely I haven't burned out my barrel already...or have I? Any suggestions would be appreciated.

[foxx]

Barrel has carbon fouling, I suspect.

[jfw432]

Barrel has carbon fouling, I suspect.

Can that not be cleaned with solvent and a brass brush or do I need a special carbon remover?

[foxx]

There are a bunch of witches brews out there if you wanna try them. Just do a search and different concoctions will pop up. I suggest using a commercial product designed for it and offered by Brownell's.
https://www.brownells.com/gun-cleaning-chemicals/solvents-degreasers/bore-solvents/c4-carbon-remover-prod31702.aspx

Copper or nylon brush

[Robinhood]

Work Hardened brass?

[jfw432]

I don't mind buying another chemical. Guess Hoppe's isn't that great at carbon deposits so maybe that's the problem. I'll give it a shot before next weekend.

I'll look into case hardening some more as well. Initial looking does make this seem like a potential problem. I am getting a greater number of split necks lately although most appear to be caused from some form of gouge that starts in the neck. I haven't figured out where that gouge is coming from yet despite all of my efforts. Either way, I've just attributed the splits to just old cases until I can find another problem. I probably have 300-400 .223 cases and although I don't track my brass, I try to rotate it fairly evenly and they're probably on their 5th or 6th reload by now. I don't crimp my bullets and my cases don't grow at all but every now and then one of them takes a bit more force to close the bolt.

[culpeper]

Check the rings for a hairline crack. Also, check the bullet diameter. I've seen undersized batch cause this as well. Doesn't matter that they shoot fine out of a different barrel. The main thing is that the problem didn't start gradually

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[OLEJOE]

Check your seating depth. The lands erode and at 3300 they get hot pretty quick. I check mine often and you would be surprised how fast they erode especially with hot loads and a hot barrel. Also check your neck tension. You stated you were getting split necks so it sounds like you need new brass or annealing. Work hardened brass makes consistent neck tension almost impossible.

[foxx]

Yep. Your brass is definitely work hardened. It doesn't matter if this is your ONLY problem (you might also have carbon built up), the brass is too hard and therefore you are not getting consistent neck tension. This causes inconsistent pressure which means inconsistent speeds.

[Texas10]

I would suspect the stock. Put that action into a good laminate or other quality stock and stop fussing with the cheap, throw-away POS plastic stock. Or if you like, I'll send you a new FV stock for just the shipping and you can see if accuracy returns.

[foxx]

Also, any cartridge that closes hard needs resizing (at least the shoulder needs to be bumped back). That is not due to hardening, just it's size. Although, I wonder if resizing hardened brass does much good. I would not know because I always anneal every 2-3 reloads anyhow. So, if I were you, I would either replace the brass or anneal it and then resize. Even then, the cases may have maxed out their useful life. For what it's worth, I have almost never had a case split. Mine lose accuracy and need to be annealed or tossed before that ever happens.

[tobnpr]

Can that not be cleaned with solvent and a brass brush or do I need a special carbon remover?Can that not be cleaned with solvent and a brass brush or do I need a special carbon remover?

You used a copper remover, but never used a common powder solvent?
Too many on the market to name, including old Hoppe's #9. I've used Wipe-Out foam for years (both copper and carbon) because I'm lazy, and use only patches in my bores. Everyone has a preference, and there's no "best" product or method. Be aware, that after stripping copper from the bore accuracy will not be restored until some foulers are shot, could need only a few to a dozen or more until a "baseline" of copper is laid back down.

I'd get the barrel stripped of all carbon and copper fouling first to rule out the simple/obvious before going down other roads.

Carbon "ring" is different, take a flashlight and check ahead of the leade for a dark ring. If present that requires a more aggressive solvent for removal.

[rmkey]

For what it's worth. I had a eabco 6.5 barrel that shot great and then opened up to 3 to 4 moa. Cleaned it with several brands of copper solvent as well as carbon remover. It would not improve so I sent it back to mfg. One day I got it back and called to ask what was the problem. Brown said it was heavily fouled with copper. I told him I had used several types of remover before I sent it in. He said they to tried several but the only thing that would get it out ended up being J B Bore paste and a stiff brush. Not saying that is your problem but symptoms are similar.
I now boron nitride my bullets and clean with Montana Extreme with a SS or nylon jag. The typical brass jag will leave you very frustrated as it contains copper that causes the solvent to turn blue! Always begin by removing carbon first then your copper solvent can get to the copper better.


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[RustyShackle]

I’ve heard it claimed that more often than not, when somebody thinks their barrel is shot out, copper fouling is generally the culprit.

Could be carbon fouling also.

Plain ol oil works best for disassociating the carbon carbon bonds, due to its unpaired electrons. So a heavy oil bath or soaking and then a good scrubbing might be in order. Olive oil works well, and is generally speaking, cheap and plentiful.

[jfw432]

Either carbon buildup or copper fouling was likely the culprit. I didn't get a lot of copper out but I used Hoppes 9 Black which helps remove carbon buildup and I kept getting more and more black out of the barrel that the regular Hoppes 9 couldn't get.

Went out today and accuracy was restored. I think the annealed cases did help a little but I ran them side by side with regular cases that I've been shooting for a while and they shot about the same give or take a little depending on how well I shot the group.

[Ratbuster]

It was fouling. After approx 100 shots my custom SS barrels exhibit a noticeable decrease in accuracy until I clean them. The more I clean the carbon out the better they shoot.

Annealing is not going to make much difference in group size. It will affect neck tension, thus velocities to a small degree which will show up as vertical dispersion at very long range.

[chetc]

i had the same issues with my 10T in 6.5 cm, after 1600 rounds i figured the barrel seen it's days, was almost ready to order a new barrel, so i figured either i will ruin this barrel or help it, JB bore pase did not quite get the carbon out, so i chanced a 600 grit valve grinding compound in the first 6-8inches of the throat area, i stroked for about 3-4 minutes vigorously, and then i finished it with JB bore paste, took it to the range and in the meantime before i done this procedure i was trying different bullets some times decent groups, most not, so i hit the range and i only shoot 200yds most of the time, best i was getting was maybe 1 1/4 to 1 3/4, my few loads were rather good, back to the loading bench i loaded the sierra 140SMK 40.8 H4350 and i am a happy camper, don't have to get a new barrel, i am near 5/8 mostly 3/4" i know its me now i use to have to give this gun a death grip, now i shoot it free recoil, last week i had 3 shots touching 4th and 5th were out to the 3/4". and since i done this the barrel cleans within 6 to 8 patches a few with a brush, before i done this it was a nightmare to clean, took forever .


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[Robinhood]

I'm interested in hard brass not affecting accuracy. we are talking hard enough to split not just a few time sized. Does powder charge variation effect accuracy? Why? How do accuracy nodes work?

[jfw432]

I'm interested in hard brass not affecting accuracy. we are talking hard enough to split not just a few time sized. Does powder charge variation effect accuracy? Why? How do accuracy nodes work?

Are you asking me how that's possible with my gun or are you asking in general? If you're asking in general, I think each one of those questions is grounds for a whole new thread so you get the answers you're seeking.

[chetc]

i started annealing after every 2 shots, never had neck or hardend brass issues, i did find annealing my brass did solve some accuracy and flyer issues, neck tension is very consistent,

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