Hi all. I've read a few posts on other websites about coating cases in a thin layer oil to get better results for fireforming. Anyone done this?
Thanks
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Hi all. I've read a few posts on other websites about coating cases in a thin layer oil to get better results for fireforming. Anyone done this?
Thanks
From what I have heard and what I know from working with lubricants, I would consider this a dangerous practice. The case uses friction against the chamber wall to reduce load on bolt face. Using lube in this location will reduce this friction and increase the possibility that a tapered case can slide out of the tapered chamber, adding to the already considerable force on the bolt face. For me it is always a dry oil free chamber and dry oil free bullet.
Visualize the case as a slippery water melon pip between your fingers.
LBD is correct. Cordite posted a vid about this, the pressure went up dramatically with an oiled case.Quote:
Originally Posted by Three O'Three
What are you fire-forming to and from ?
Oiled cases as far as I'm aware were only ever used in pressure testing using the copper crusher method as well as in the ww1 Austrian schwarzloss blow back operated machine gun plus a few others.
Not a practice I would ever consider myself. All the fire forming I've ever done has been with fast shotgun powders and either wax plugs or a light well lubed lead bullet.
Stay off that site they are crazy, Oiled case were only used to test the locking lug strength at Amories and Arsenals by people that knew what they were doingQuote:
Originally Posted by Three O'Three
and using state of the art equipment , What cases are you fire forming? If it is a hunting rifle and the cases are the standard calibre for that rifle you are wasting
Components for no good reason, Just work your loads up to find a safe maximum along the way you will find a node-point to start fine tuning your load from,
The difference in velocity between a virgin case and a fire formed one is only noticeable at extend range.
I oil the cases when fireforming 303 cases to 7x57R using Green Dot powder. The whole process is incremental: try it at a safe level and work up until the desired effect is achieved. It is fairly obvious when the case is not going to reform more by using a further increment of powder. That is definitely the point to stop increasing powder charges. The oil helps to reduce thinning of the web of the case. I tried Imperial Sizing Die Wax, CRC, and Arpolube 372 (thin gun oil). All worked about the same.