Yes! You are referring to the 777 crud ring. This has been discussed to no end. Basically you need to use the least powerful primer you can. If you have a rifle that can be converted back to musket caps go that way. If you can only use 209 primers try to go to the coolest which has been noted as CCI However some are reporting accuracy problems with CCI Primers. I would recommed Winchester as they worked as good for me as any. There are conversions available to switch from 209 to a .25ACP piece of brass with a rifle primer installed. Expensive and a bit more problem but it pretty much solves the severe crud ring. I have the conversion and it works. Other option is to eliminate the 777 and try the new Black Mag3 powder which is working great for me so far. It is difficult to find but Midsouth Shooters Supply has it but it requires a $20.00 Hazmat fee so team up with a lot of guys and buy alot at once. If you want to talk more email me at:
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