Home Forums Hunting & Shooting Ask The Gunwriters .243 Winchester - Bad fouling hombre

So I have a Ruger M77 "tanger" chambered for this cartridge and it has always been one of my most difficult rifle to clean......

I recently embarked on load development with the Hornady V-max in 87 grain to more appropriately match my aging style 😂. I used to push the 55 grain NBT with H414 out of it, but decided I wanted to preserve the barrel, and I needed something new to do.

Anyway, I've tried several powders (Varget, H414, IMR 4451, IMR 4831) and Varget and IMR 4831 showed promise, but not what I was hoping for. So I started doing some web research and found many references to the .243 Winchester being a "barrel burner" and a cartridge that fouls much easier and worse than other cartridges. I was already in the middle of cleaning it up for the next range session, and like always it was taking an inordinate amount of time and doses of WipeOut. I dug around my cleaning drawer and found some Montana Copper Killer and Copper Cream and went to town on it yesterday. I've been amazed at the amount of effort it has taken, and the amount of dirty patches (blue/black at first, now just faint blue) to get to the point I am at, and I'm not down to the bare metal yet. Before I shoot my next set of loads I am going to have a good friend look at the barrel with a borescope to make sure I'm not wasting my time with a firecracked shotgun for the first 6 inches.

Anyway, are the reputations of being a barrel burner and a bad fouling hombre, as compared to other cartridges valid, or just interweb garbage?

If you eventually get it borescope clean and it's not toast, do the DBC treatment.

DF

My 700 Classic .250 Savage was like that. Mule Deer suggested, in a thread similar to this one, scrubbing with a tight patch and valve lapping compound. I don't remember the grits he recommended, and all I could find at my parts store was a compound that degraded as you used it, coarse to very fine, and water soluble. When it felt smooth and easy, I swabbed it clean, then hit it with JB compound. From fouling and deteriorating accuracy after as few as twelve rounds, it'll now go 70-80 before I see a need to clean, and then it takes very little effort. Accuracy is 3/4" for 100gr Hornadys, 6/10" for 100gr NBTs, and sub-1/2" with 75gr Sierra HPs and V-max. And this without DBC. Yet.

Yes a 243 can be a barrel burner, I have owned much worse a 6-284. borescope it after you get all the copper and carbon out, if it is not completely gone try a Tubb firelapping kit to smooth things out. sometimes this is all it takes, then you can do the DBC if you choose afterward

I used the Tubbs final finish on a rough bore and then DBC treatment, it was a big improvement on fouling.

This is what I would do for an already toasty barrel. Then JB, wipe out and DBC.

All of the 6mms larger than the 6x47 Lapua and maybe it too are barrel burners. The smaller the bore the more likely this is to occur. The 243 got a reputation for pressure excursions due to a number of factors, variation in chambers and throats, early wear scorching or crazing of the throat, bulk lots of 7828 have had allegations of mysterious pressure spikes, and probably several other factors such as case geometry, short neck, and other unknowns. The 6mm Remington with it's longer neck does not have the same reputation for pressure spikes but is only slightly better on barrel erosion.

After the Tubbs and DBC I would decide quickly on if it is time for a new barrel or not. If it doesn't shoot well with your previous accurate load maybe try seating it longer and if that doesn't do it probably better to not spend to much time and ammo on it.

Bought the wife a new Winchester Model 70 XTR in in 1976 if I remember correctly.. Never did shoot well, tried everything, different loads scopes bedding etc. Always fouled hard as well. Fast forward to the 2000's I found out why. A bore scope showed a really crappy barrel. Also a lot of alligator skin in the leade, maybe 200 rounds total. It now has a 308 barrel on it.

Ruger 77 rifles with the tang safety had contract barrels from Wilson for about $6 apiece. It is not a cartridge problem it is a a cheap barrel problem. Fire lapping the barrel might help some.

Yeah, those tang safety models were hit or miss. That being said, I've noticed my 243's all suffered from the carbon donuts a lot faster than my other rifles. A brass brush and lots of scrubbing to remove it.

Yep, I have had tangers with very good barrels, and very bad barrels. The worst was a 7x57 that refused to shoot 3-shot groups better than 2-3" at 100 yards. In my bore-scope it was a little rough, but have seen far worse shoot OK, so slugged the barrel: The "tight" spots went .287", and there were several loose spots. Neither fire-lapping or Dyna Bore-Coat will helps that sort of barrel.

Ruger m-77 serial number 1 was a 243, Bill’s favorite caliber. Most of the early ones had a Douglas barrel, probably not lapped. Chances are your barrel is smoked. Give the gun a second life and put a new barrel on it.

Upon inspection with a bore scope I pronounce it “smoked”🙁🙁.

Congratulations you are on the way to a new barrel. The 243 has always been a favorite but if I were setting up a new barrel now I would probably go 6mm Creedmoor. The CM has practically the same capacity as the 243 but the longer neck and better case geometry should contribute to longer barrel life and more uniform pressures. Not sure about the carbon build up probably only slightly less than the 243.

Had a Tang 77V in 6 RM - shot Clover-leafs....as in one hole. Yes, barrels are much more consistent now they are in-house.

I had a Sako Forester 243 with light pitting, fouled it shot great........every barrel is unto itself.

Have to somewhat agree with you, just not a big gaymoor fan, I would go with a 6mm Remington with a 1-8" twist but would have a hard time going back to a 243 Win

Tahat is just what I did except in 6mm AI format. If I had to do it over again I would do a 1-7.5 twist so I could play with all the bullets. Some of the 115s stabilize in the 1-8 but I am sure I am loosing some BC almost to the point I am better off with the 105s-110s.