35 Rem 336 chamber cast

[robroy]

I just did an impact cast of my chamber. It extends about a 1/2" up the rifeling but the rifeling is barely visable on the cast. At the muzzle the rifeling is clearly visable on the cast. For about 1/32" forward of the case the diameter is 0.3650". The rest of the cast measures 0.3586".

It seems to me I should be using pills of about 0.361 or0.362. The Ranch Dogs I cast with my 2 cavity are dropping at 0.360 or so as advertised. I'm going to cast some tonight to be sure. All of them I've cast so far have been sized to 0.359.

I may be looking for a new mould that casts big or failing that lapping my mould bigger.

What do you fine folks think?

Yes it's a microgroove

[wmitty]

What kind of accuracy are you getting with the slugs sized to .359"? I'm not shooting a .35 Rem but if I were I'd try to use the largest diameter slug the chamber neck would allow... sounds like the typical very short throat was carried over from Marlin. Have you tried shooting as cast diameter/ tumble lubing?

[robroy]

Yup it's a marlin. I'll try to post a picture. the one I took with my Phone was too grainy