Vinnie, I can tell you first hand you dont want to build a 4570 on a springfield action. I put them in the same class as cast iron actions. the locking system is not strong enough. I have been building double rifles for 40 years and semi retired. If you want a cheap action to build a 4570 on try a Baikal. They are very strong and work well if you keep the pressure to 35,000 lb. I have built 17 to date on them. I still have the first one and have put 40 shots through it that are over what is recomended for a Marlin. This certain gun has over 600 rounds fired through it. 54 grs. imr. 3031 with 350 gr. Hornady and ww primer. This is the standard load i regulate them for. I use the 20 gauge for 4570 it makes a nice 8 lb Rifle. Rich [image]

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