Rossi Rifleman

Afternoon',

This is probably a waste of time to read so my apologies in advance.

A local phun show provided me with 300 38 special cases and 100 cast 158 grain lead round nose flat point projectiles.

Now that I have cleaned, de-primed, resized cases and have longer bullets I want to load these for very light plinking. The manual I am using is the 2017 Hodgden Annual Manual, specifically page 154. The only confusion is the manual states 158 grain cast semi wad cutter bullets with 2.7 grains of Trail Boss (I want to use up this powder before trying any other ones) for 661FPS and 11,400PSI. Obviously, the bullets I have are not semi wad cutters. Is it still safe to use this load with cast lead round nose flat points? I'm guessing it's perfectly fine however it's better to ask for opinions than to just wing it.

Thank you in advance for the help.

Shape not usually unless the shape forces you to alter the overall length of the load. Diameter and weight and construction will mater to one extent or the other. Reducing OAL will increase the operating pressure. Lengthening it will decrease pressure. The only concern with TB is it doesn't like to be compressed, but I suspect that load is no where near compressing.

Make smoke,

I'm going to say that the shape CAN change the load data but IN THIS PARTICULAR CASEI suspect it will be minutely.

OAL is Over All Length or where the point of the bullet ends up.
Your combustion chamber is essentially comprised of the brass case and where the base of the bullet ends up. (And ALSO what shape the base of the bullet takes, I've seen FMJ 9mm Winchesters in both flat base and domed base for example.)

So IF your base style is the same and your bullet length is the same then holding your OAL the same should give you pretty much the same results. IF however your bullet lengths are different you are changing the size of the initial combustion chamber by seating to the same OAL.

Another factor that might come into play is how much room you have off the lands. When you change bullet profiles you may wind up closer or further away from the lands than the data bullet. In extreme cases this may result in jamming the bullet into the lands which will typically raise pressures. It may even prevent the breach from closing all the way.